SDK for Go V2 を使用した Lambda の例 - AWS SDK コード例

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SDK for Go V2 を使用した Lambda の例

次のコード例は、Lambda で AWS SDK for Go V2 を使用してアクションを実行し、一般的なシナリオを実装する方法を示しています。

アクションはより大きなプログラムからのコードの抜粋であり、コンテキスト内で実行する必要があります。アクションは個々のサービス機能を呼び出す方法を示していますが、関連するシナリオやサービス間の例ではアクションのコンテキストが確認できます。

「シナリオ」は、同じサービス内で複数の関数を呼び出して、特定のタスクを実行する方法を示すコード例です。

各例には、 へのリンクが含まれています。このリンクには GitHub、コンテキスト内でコードをセットアップして実行する方法の手順が記載されています。

開始方法

次のコード例では、Lambda の使用を開始する方法について示しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

package main import ( "context" "fmt" "github.com/aws/aws-sdk-go-v2/aws" "github.com/aws/aws-sdk-go-v2/config" "github.com/aws/aws-sdk-go-v2/service/lambda" ) // main uses the AWS SDK for Go (v2) to create an AWS Lambda client and list up to 10 // functions in your account. // This example uses the default settings specified in your shared credentials // and config files. func main() { sdkConfig, err := config.LoadDefaultConfig(context.TODO()) if err != nil { fmt.Println("Couldn't load default configuration. Have you set up your AWS account?") fmt.Println(err) return } lambdaClient := lambda.NewFromConfig(sdkConfig) maxItems := 10 fmt.Printf("Let's list up to %v functions for your account.\n", maxItems) result, err := lambdaClient.ListFunctions(context.TODO(), &lambda.ListFunctionsInput{ MaxItems: aws.Int32(int32(maxItems)), }) if err != nil { fmt.Printf("Couldn't list functions for your account. Here's why: %v\n", err) return } if len(result.Functions) == 0 { fmt.Println("You don't have any functions!") } else { for _, function := range result.Functions { fmt.Printf("\t%v\n", *function.FunctionName) } } }
  • API の詳細については、「 API リファレンスListFunctions」の「」を参照してください。 AWS SDK for Go

アクション

次の例は、CreateFunction を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // CreateFunction creates a new Lambda function from code contained in the zipPackage // buffer. The specified handlerName must match the name of the file and function // contained in the uploaded code. The role specified by iamRoleArn is assumed by // Lambda and grants specific permissions. // When the function already exists, types.StateActive is returned. // When the function is created, a lambda.FunctionActiveV2Waiter is used to wait until the // function is active. func (wrapper FunctionWrapper) CreateFunction(functionName string, handlerName string, iamRoleArn *string, zipPackage *bytes.Buffer) types.State { var state types.State _, err := wrapper.LambdaClient.CreateFunction(context.TODO(), &lambda.CreateFunctionInput{ Code: &types.FunctionCode{ZipFile: zipPackage.Bytes()}, FunctionName: aws.String(functionName), Role: iamRoleArn, Handler: aws.String(handlerName), Publish: true, Runtime: types.RuntimePython38, }) if err != nil { var resConflict *types.ResourceConflictException if errors.As(err, &resConflict) { log.Printf("Function %v already exists.\n", functionName) state = types.StateActive } else { log.Panicf("Couldn't create function %v. Here's why: %v\n", functionName, err) } } else { waiter := lambda.NewFunctionActiveV2Waiter(wrapper.LambdaClient) funcOutput, err := waiter.WaitForOutput(context.TODO(), &lambda.GetFunctionInput{ FunctionName: aws.String(functionName)}, 1*time.Minute) if err != nil { log.Panicf("Couldn't wait for function %v to be active. Here's why: %v\n", functionName, err) } else { state = funcOutput.Configuration.State } } return state }
  • API の詳細については、「 API リファレンスCreateFunction」の「」を参照してください。 AWS SDK for Go

次の例は、DeleteFunction を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // DeleteFunction deletes the Lambda function specified by functionName. func (wrapper FunctionWrapper) DeleteFunction(functionName string) { _, err := wrapper.LambdaClient.DeleteFunction(context.TODO(), &lambda.DeleteFunctionInput{ FunctionName: aws.String(functionName), }) if err != nil { log.Panicf("Couldn't delete function %v. Here's why: %v\n", functionName, err) } }
  • API の詳細については、「 API リファレンスDeleteFunction」の「」を参照してください。 AWS SDK for Go

次の例は、GetFunction を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // GetFunction gets data about the Lambda function specified by functionName. func (wrapper FunctionWrapper) GetFunction(functionName string) types.State { var state types.State funcOutput, err := wrapper.LambdaClient.GetFunction(context.TODO(), &lambda.GetFunctionInput{ FunctionName: aws.String(functionName), }) if err != nil { log.Panicf("Couldn't get function %v. Here's why: %v\n", functionName, err) } else { state = funcOutput.Configuration.State } return state }
  • API の詳細については、「 API リファレンスGetFunction」の「」を参照してください。 AWS SDK for Go

次の例は、Invoke を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。用例一覧を検索し、AWS コードサンプルリポジトリでの設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // Invoke invokes the Lambda function specified by functionName, passing the parameters // as a JSON payload. When getLog is true, types.LogTypeTail is specified, which tells // Lambda to include the last few log lines in the returned result. func (wrapper FunctionWrapper) Invoke(functionName string, parameters any, getLog bool) *lambda.InvokeOutput { logType := types.LogTypeNone if getLog { logType = types.LogTypeTail } payload, err := json.Marshal(parameters) if err != nil { log.Panicf("Couldn't marshal parameters to JSON. Here's why %v\n", err) } invokeOutput, err := wrapper.LambdaClient.Invoke(context.TODO(), &lambda.InvokeInput{ FunctionName: aws.String(functionName), LogType: logType, Payload: payload, }) if err != nil { log.Panicf("Couldn't invoke function %v. Here's why: %v\n", functionName, err) } return invokeOutput }
  • API の詳細については、「AWS SDK for Go API リファレンス」の「Invoke」を参照してください。

次の例は、ListFunctions を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // ListFunctions lists up to maxItems functions for the account. This function uses a // lambda.ListFunctionsPaginator to paginate the results. func (wrapper FunctionWrapper) ListFunctions(maxItems int) []types.FunctionConfiguration { var functions []types.FunctionConfiguration paginator := lambda.NewListFunctionsPaginator(wrapper.LambdaClient, &lambda.ListFunctionsInput{ MaxItems: aws.Int32(int32(maxItems)), }) for paginator.HasMorePages() && len(functions) < maxItems { pageOutput, err := paginator.NextPage(context.TODO()) if err != nil { log.Panicf("Couldn't list functions for your account. Here's why: %v\n", err) } functions = append(functions, pageOutput.Functions...) } return functions }
  • API の詳細については、「 API リファレンスListFunctions」の「」を参照してください。 AWS SDK for Go

次の例は、UpdateFunctionCode を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // UpdateFunctionCode updates the code for the Lambda function specified by functionName. // The existing code for the Lambda function is entirely replaced by the code in the // zipPackage buffer. After the update action is called, a lambda.FunctionUpdatedV2Waiter // is used to wait until the update is successful. func (wrapper FunctionWrapper) UpdateFunctionCode(functionName string, zipPackage *bytes.Buffer) types.State { var state types.State _, err := wrapper.LambdaClient.UpdateFunctionCode(context.TODO(), &lambda.UpdateFunctionCodeInput{ FunctionName: aws.String(functionName), ZipFile: zipPackage.Bytes(), }) if err != nil { log.Panicf("Couldn't update code for function %v. Here's why: %v\n", functionName, err) } else { waiter := lambda.NewFunctionUpdatedV2Waiter(wrapper.LambdaClient) funcOutput, err := waiter.WaitForOutput(context.TODO(), &lambda.GetFunctionInput{ FunctionName: aws.String(functionName)}, 1*time.Minute) if err != nil { log.Panicf("Couldn't wait for function %v to be active. Here's why: %v\n", functionName, err) } else { state = funcOutput.Configuration.State } } return state }
  • API の詳細については、「 API リファレンスUpdateFunctionCode」の「」を参照してください。 AWS SDK for Go

次の例は、UpdateFunctionConfiguration を使用する方法を説明しています。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // UpdateFunctionConfiguration updates a map of environment variables configured for // the Lambda function specified by functionName. func (wrapper FunctionWrapper) UpdateFunctionConfiguration(functionName string, envVars map[string]string) { _, err := wrapper.LambdaClient.UpdateFunctionConfiguration(context.TODO(), &lambda.UpdateFunctionConfigurationInput{ FunctionName: aws.String(functionName), Environment: &types.Environment{Variables: envVars}, }) if err != nil { log.Panicf("Couldn't update configuration for %v. Here's why: %v", functionName, err) } }
  • API の詳細については、「 API リファレンスUpdateFunctionConfiguration」の「」を参照してください。 AWS SDK for Go

シナリオ

次のコード例は、Lambda 関数を使用して既知の Amazon Cognito ユーザーを自動的に確認する方法を示しています。

  • PreSignUp トリガーの Lambda 関数を呼び出すようにユーザープールを設定します。

  • Amazon Cognito でユーザーをサインアップします。

  • Lambda 関数は DynamoDB テーブルをスキャンし、既知のユーザーを自動的に確認します。

  • 新しいユーザーとしてサインインし、リソースをクリーンアップします。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

コマンドプロンプトからインタラクティブのシナリオを実行します。

// AutoConfirm separates the steps of this scenario into individual functions so that // they are simpler to read and understand. type AutoConfirm struct { helper IScenarioHelper questioner demotools.IQuestioner resources Resources cognitoActor *actions.CognitoActions } // NewAutoConfirm constructs a new auto confirm runner. func NewAutoConfirm(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) AutoConfirm { scenario := AutoConfirm{ helper: helper, questioner: questioner, resources: Resources{}, cognitoActor: &actions.CognitoActions{CognitoClient: cognitoidentityprovider.NewFromConfig(sdkConfig)}, } scenario.resources.init(scenario.cognitoActor, questioner) return scenario } // AddPreSignUpTrigger adds a Lambda handler as an invocation target for the PreSignUp trigger. func (runner *AutoConfirm) AddPreSignUpTrigger(userPoolId string, functionArn string) { log.Printf("Let's add a Lambda function to handle the PreSignUp trigger from Cognito.\n" + "This trigger happens when a user signs up, and lets your function take action before the main Cognito\n" + "sign up processing occurs.\n") err := runner.cognitoActor.UpdateTriggers( userPoolId, actions.TriggerInfo{Trigger: actions.PreSignUp, HandlerArn: aws.String(functionArn)}) if err != nil { panic(err) } log.Printf("Lambda function %v added to user pool %v to handle the PreSignUp trigger.\n", functionArn, userPoolId) } // SignUpUser signs up a user from the known user table with a password you specify. func (runner *AutoConfirm) SignUpUser(clientId string, usersTable string) (string, string) { log.Println("Let's sign up a user to your Cognito user pool. When the user's email matches an email in the\n" + "DynamoDB known users table, it is automatically verified and the user is confirmed.") knownUsers, err := runner.helper.GetKnownUsers(usersTable) if err != nil { panic(err) } userChoice := runner.questioner.AskChoice("Which user do you want to use?\n", knownUsers.UserNameList()) user := knownUsers.Users[userChoice] var signedUp bool var userConfirmed bool password := runner.questioner.AskPassword("Enter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.\n"+ "(the password will not display as you type):", 8) for !signedUp { log.Printf("Signing up user '%v' with email '%v' to Cognito.\n", user.UserName, user.UserEmail) userConfirmed, err = runner.cognitoActor.SignUp(clientId, user.UserName, password, user.UserEmail) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { password = runner.questioner.AskPassword("Enter another password:", 8) } else { panic(err) } } else { signedUp = true } } log.Printf("User %v signed up, confirmed = %v.\n", user.UserName, userConfirmed) log.Println(strings.Repeat("-", 88)) return user.UserName, password } // SignInUser signs in a user. func (runner *AutoConfirm) SignInUser(clientId string, userName string, password string) string { runner.questioner.Ask("Press Enter when you're ready to continue.") log.Printf("Let's sign in as %v...\n", userName) authResult, err := runner.cognitoActor.SignIn(clientId, userName, password) if err != nil { panic(err) } log.Printf("Successfully signed in. Your access token starts with: %v...\n", (*authResult.AccessToken)[:10]) log.Println(strings.Repeat("-", 88)) return *authResult.AccessToken } // Run runs the scenario. func (runner *AutoConfirm) Run(stackName string) { defer func() { if r := recover(); r != nil { log.Println("Something went wrong with the demo.") runner.resources.Cleanup() } }() log.Println(strings.Repeat("-", 88)) log.Printf("Welcome\n") log.Println(strings.Repeat("-", 88)) stackOutputs, err := runner.helper.GetStackOutputs(stackName) if err != nil { panic(err) } runner.resources.userPoolId = stackOutputs["UserPoolId"] runner.helper.PopulateUserTable(stackOutputs["TableName"]) runner.AddPreSignUpTrigger(stackOutputs["UserPoolId"], stackOutputs["AutoConfirmFunctionArn"]) runner.resources.triggers = append(runner.resources.triggers, actions.PreSignUp) userName, password := runner.SignUpUser(stackOutputs["UserPoolClientId"], stackOutputs["TableName"]) runner.helper.ListRecentLogEvents(stackOutputs["AutoConfirmFunction"]) runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, runner.SignInUser(stackOutputs["UserPoolClientId"], userName, password)) runner.resources.Cleanup() log.Println(strings.Repeat("-", 88)) log.Println("Thanks for watching!") log.Println(strings.Repeat("-", 88)) }

Lambda 関数を使用してPreSignUpトリガーを処理します。

const TABLE_NAME = "TABLE_NAME" // UserInfo defines structured user data that can be marshalled to a DynamoDB format. type UserInfo struct { UserName string `dynamodbav:"UserName"` UserEmail string `dynamodbav:"UserEmail"` } // GetKey marshals the user email value to a DynamoDB key format. func (user UserInfo) GetKey() map[string]dynamodbtypes.AttributeValue { userEmail, err := attributevalue.Marshal(user.UserEmail) if err != nil { panic(err) } return map[string]dynamodbtypes.AttributeValue{"UserEmail": userEmail} } type handler struct { dynamoClient *dynamodb.Client } // HandleRequest handles the PreSignUp event by looking up a user in an Amazon DynamoDB table and // specifying whether they should be confirmed and verified. func (h *handler) HandleRequest(ctx context.Context, event events.CognitoEventUserPoolsPreSignup) (events.CognitoEventUserPoolsPreSignup, error) { log.Printf("Received presignup from %v for user '%v'", event.TriggerSource, event.UserName) if event.TriggerSource != "PreSignUp_SignUp" { // Other trigger sources, such as PreSignUp_AdminInitiateAuth, ignore the response from this handler. return event, nil } tableName := os.Getenv(TABLE_NAME) user := UserInfo{ UserEmail: event.Request.UserAttributes["email"], } log.Printf("Looking up email %v in table %v.\n", user.UserEmail, tableName) output, err := h.dynamoClient.GetItem(ctx, &dynamodb.GetItemInput{ Key: user.GetKey(), TableName: aws.String(tableName), }) if err != nil { log.Printf("Error looking up email %v.\n", user.UserEmail) return event, err } if output.Item == nil { log.Printf("Email %v not found. Email verification is required.\n", user.UserEmail) return event, err } err = attributevalue.UnmarshalMap(output.Item, &user) if err != nil { log.Printf("Couldn't unmarshal DynamoDB item. Here's why: %v\n", err) return event, err } if user.UserName != event.UserName { log.Printf("UserEmail %v found, but stored UserName '%v' does not match supplied UserName '%v'. Verification is required.\n", user.UserEmail, user.UserName, event.UserName) } else { log.Printf("UserEmail %v found with matching UserName %v. User is confirmed.\n", user.UserEmail, user.UserName) event.Response.AutoConfirmUser = true event.Response.AutoVerifyEmail = true } return event, err } func main() { sdkConfig, err := config.LoadDefaultConfig(context.TODO()) if err != nil { log.Panicln(err) } h := handler{ dynamoClient: dynamodb.NewFromConfig(sdkConfig), } lambda.Start(h.HandleRequest) }

一般的なタスクを実行する構造体を作成します。

// IScenarioHelper defines common functions used by the workflows in this example. type IScenarioHelper interface { Pause(secs int) GetStackOutputs(stackName string) (actions.StackOutputs, error) PopulateUserTable(tableName string) GetKnownUsers(tableName string) (actions.UserList, error) AddKnownUser(tableName string, user actions.User) ListRecentLogEvents(functionName string) } // ScenarioHelper contains AWS wrapper structs used by the workflows in this example. type ScenarioHelper struct { questioner demotools.IQuestioner dynamoActor *actions.DynamoActions cfnActor *actions.CloudFormationActions cwlActor *actions.CloudWatchLogsActions isTestRun bool } // NewScenarioHelper constructs a new scenario helper. func NewScenarioHelper(sdkConfig aws.Config, questioner demotools.IQuestioner) ScenarioHelper { scenario := ScenarioHelper{ questioner: questioner, dynamoActor: &actions.DynamoActions{DynamoClient: dynamodb.NewFromConfig(sdkConfig)}, cfnActor: &actions.CloudFormationActions{CfnClient: cloudformation.NewFromConfig(sdkConfig)}, cwlActor: &actions.CloudWatchLogsActions{CwlClient: cloudwatchlogs.NewFromConfig(sdkConfig)}, } return scenario } // Pause waits for the specified number of seconds. func (helper ScenarioHelper) Pause(secs int) { if !helper.isTestRun { time.Sleep(time.Duration(secs) * time.Second) } } // GetStackOutputs gets the outputs from the specified CloudFormation stack in a structured format. func (helper ScenarioHelper) GetStackOutputs(stackName string) (actions.StackOutputs, error) { return helper.cfnActor.GetOutputs(stackName), nil } // PopulateUserTable fills the known user table with example data. func (helper ScenarioHelper) PopulateUserTable(tableName string) { log.Printf("First, let's add some users to the DynamoDB %v table we'll use for this example.\n", tableName) err := helper.dynamoActor.PopulateTable(tableName) if err != nil { panic(err) } } // GetKnownUsers gets the users from the known users table in a structured format. func (helper ScenarioHelper) GetKnownUsers(tableName string) (actions.UserList, error) { knownUsers, err := helper.dynamoActor.Scan(tableName) if err != nil { log.Printf("Couldn't get known users from table %v. Here's why: %v\n", tableName, err) } return knownUsers, err } // AddKnownUser adds a user to the known users table. func (helper ScenarioHelper) AddKnownUser(tableName string, user actions.User) { log.Printf("Adding user '%v' with email '%v' to the DynamoDB known users table...\n", user.UserName, user.UserEmail) err := helper.dynamoActor.AddUser(tableName, user) if err != nil { panic(err) } } // ListRecentLogEvents gets the most recent log stream and events for the specified Lambda function and displays them. func (helper ScenarioHelper) ListRecentLogEvents(functionName string) { log.Println("Waiting a few seconds to let Lambda write to CloudWatch Logs...") helper.Pause(10) log.Println("Okay, let's check the logs to find what's happened recently with your Lambda function.") logStream, err := helper.cwlActor.GetLatestLogStream(functionName) if err != nil { panic(err) } log.Printf("Getting some recent events from log stream %v\n", *logStream.LogStreamName) events, err := helper.cwlActor.GetLogEvents(functionName, *logStream.LogStreamName, 10) if err != nil { panic(err) } for _, event := range events { log.Printf("\t%v", *event.Message) } log.Println(strings.Repeat("-", 88)) }

Amazon Cognito アクションをラップする構造体を作成します。

type CognitoActions struct { CognitoClient *cognitoidentityprovider.Client } // Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger. type Trigger int const ( PreSignUp Trigger = iota UserMigration PostAuthentication ) type TriggerInfo struct { Trigger Trigger HandlerArn *string } // UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value, // it is removed from the user pool. func (actor CognitoActions) UpdateTriggers(userPoolId string, triggers ...TriggerInfo) error { output, err := actor.CognitoClient.DescribeUserPool(context.TODO(), &cognitoidentityprovider.DescribeUserPoolInput{ UserPoolId: aws.String(userPoolId), }) if err != nil { log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err) return err } lambdaConfig := output.UserPool.LambdaConfig for _, trigger := range triggers { switch trigger.Trigger { case PreSignUp: lambdaConfig.PreSignUp = trigger.HandlerArn case UserMigration: lambdaConfig.UserMigration = trigger.HandlerArn case PostAuthentication: lambdaConfig.PostAuthentication = trigger.HandlerArn } } _, err = actor.CognitoClient.UpdateUserPool(context.TODO(), &cognitoidentityprovider.UpdateUserPoolInput{ UserPoolId: aws.String(userPoolId), LambdaConfig: lambdaConfig, }) if err != nil { log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err) } return err } // SignUp signs up a user with Amazon Cognito. func (actor CognitoActions) SignUp(clientId string, userName string, password string, userEmail string) (bool, error) { confirmed := false output, err := actor.CognitoClient.SignUp(context.TODO(), &cognitoidentityprovider.SignUpInput{ ClientId: aws.String(clientId), Password: aws.String(password), Username: aws.String(userName), UserAttributes: []types.AttributeType{ {Name: aws.String("email"), Value: aws.String(userEmail)}, }, }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err) } } else { confirmed = output.UserConfirmed } return confirmed, err } // SignIn signs in a user to Amazon Cognito using a username and password authentication flow. func (actor CognitoActions) SignIn(clientId string, userName string, password string) (*types.AuthenticationResultType, error) { var authResult *types.AuthenticationResultType output, err := actor.CognitoClient.InitiateAuth(context.TODO(), &cognitoidentityprovider.InitiateAuthInput{ AuthFlow: "USER_PASSWORD_AUTH", ClientId: aws.String(clientId), AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password}, }) if err != nil { var resetRequired *types.PasswordResetRequiredException if errors.As(err, &resetRequired) { log.Println(*resetRequired.Message) } else { log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err) } } else { authResult = output.AuthenticationResult } return authResult, err } // ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code // to the user's configured notification destination, such as email. func (actor CognitoActions) ForgotPassword(clientId string, userName string) (*types.CodeDeliveryDetailsType, error) { output, err := actor.CognitoClient.ForgotPassword(context.TODO(), &cognitoidentityprovider.ForgotPasswordInput{ ClientId: aws.String(clientId), Username: aws.String(userName), }) if err != nil { log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err) } return output.CodeDeliveryDetails, err } // ConfirmForgotPassword confirms a user with a confirmation code and a new password. func (actor CognitoActions) ConfirmForgotPassword(clientId string, code string, userName string, password string) error { _, err := actor.CognitoClient.ConfirmForgotPassword(context.TODO(), &cognitoidentityprovider.ConfirmForgotPasswordInput{ ClientId: aws.String(clientId), ConfirmationCode: aws.String(code), Password: aws.String(password), Username: aws.String(userName), }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err) } } return err } // DeleteUser removes a user from the user pool. func (actor CognitoActions) DeleteUser(userAccessToken string) error { _, err := actor.CognitoClient.DeleteUser(context.TODO(), &cognitoidentityprovider.DeleteUserInput{ AccessToken: aws.String(userAccessToken), }) if err != nil { log.Printf("Couldn't delete user. Here's why: %v\n", err) } return err } // AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user // in a state that requires they enter a new password next time they sign in. func (actor CognitoActions) AdminCreateUser(userPoolId string, userName string, userEmail string) error { _, err := actor.CognitoClient.AdminCreateUser(context.TODO(), &cognitoidentityprovider.AdminCreateUserInput{ UserPoolId: aws.String(userPoolId), Username: aws.String(userName), MessageAction: types.MessageActionTypeSuppress, UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}}, }) if err != nil { var userExists *types.UsernameExistsException if errors.As(err, &userExists) { log.Printf("User %v already exists in the user pool.", userName) err = nil } else { log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err) } } return err } // AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a // temporary password. func (actor CognitoActions) AdminSetUserPassword(userPoolId string, userName string, password string) error { _, err := actor.CognitoClient.AdminSetUserPassword(context.TODO(), &cognitoidentityprovider.AdminSetUserPasswordInput{ Password: aws.String(password), UserPoolId: aws.String(userPoolId), Username: aws.String(userName), Permanent: true, }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err) } } return err }

DynamoDB アクションをラップする構造体を作成します。

// DynamoActions encapsulates the Amazon Simple Notification Service (Amazon SNS) actions // used in the examples. type DynamoActions struct { DynamoClient *dynamodb.Client } // User defines structured user data. type User struct { UserName string UserEmail string LastLogin *LoginInfo `dynamodbav:",omitempty"` } // LoginInfo defines structured custom login data. type LoginInfo struct { UserPoolId string ClientId string Time string } // UserList defines a list of users. type UserList struct { Users []User } // UserNameList returns the usernames contained in a UserList as a list of strings. func (users *UserList) UserNameList() []string { names := make([]string, len(users.Users)) for i := 0; i < len(users.Users); i++ { names[i] = users.Users[i].UserName } return names } // PopulateTable adds a set of test users to the table. func (actor DynamoActions) PopulateTable(tableName string) error { var err error var item map[string]types.AttributeValue var writeReqs []types.WriteRequest for i := 1; i < 4; i++ { item, err = attributevalue.MarshalMap(User{UserName: fmt.Sprintf("test_user_%v", i), UserEmail: fmt.Sprintf("test_email_%v@example.com", i)}) if err != nil { log.Printf("Couldn't marshall user into DynamoDB format. Here's why: %v\n", err) return err } writeReqs = append(writeReqs, types.WriteRequest{PutRequest: &types.PutRequest{Item: item}}) } _, err = actor.DynamoClient.BatchWriteItem(context.TODO(), &dynamodb.BatchWriteItemInput{ RequestItems: map[string][]types.WriteRequest{tableName: writeReqs}, }) if err != nil { log.Printf("Couldn't populate table %v with users. Here's why: %v\n", tableName, err) } return err } // Scan scans the table for all items. func (actor DynamoActions) Scan(tableName string) (UserList, error) { var userList UserList output, err := actor.DynamoClient.Scan(context.TODO(), &dynamodb.ScanInput{ TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't scan table %v for items. Here's why: %v\n", tableName, err) } else { err = attributevalue.UnmarshalListOfMaps(output.Items, &userList.Users) if err != nil { log.Printf("Couldn't unmarshal items into users. Here's why: %v\n", err) } } return userList, err } // AddUser adds a user item to a table. func (actor DynamoActions) AddUser(tableName string, user User) error { userItem, err := attributevalue.MarshalMap(user) if err != nil { log.Printf("Couldn't marshall user to item. Here's why: %v\n", err) } _, err = actor.DynamoClient.PutItem(context.TODO(), &dynamodb.PutItemInput{ Item: userItem, TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't put item in table %v. Here's why: %v", tableName, err) } return err }

CloudWatch Logs アクションをラップする構造体を作成します。

type CloudWatchLogsActions struct { CwlClient *cloudwatchlogs.Client } // GetLatestLogStream gets the most recent log stream for a Lambda function. func (actor CloudWatchLogsActions) GetLatestLogStream(functionName string) (types.LogStream, error) { var logStream types.LogStream logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName) output, err := actor.CwlClient.DescribeLogStreams(context.TODO(), &cloudwatchlogs.DescribeLogStreamsInput{ Descending: aws.Bool(true), Limit: aws.Int32(1), LogGroupName: aws.String(logGroupName), OrderBy: types.OrderByLastEventTime, }) if err != nil { log.Printf("Couldn't get log streams for log group %v. Here's why: %v\n", logGroupName, err) } else { logStream = output.LogStreams[0] } return logStream, err } // GetLogEvents gets the most recent eventCount events from the specified log stream. func (actor CloudWatchLogsActions) GetLogEvents(functionName string, logStreamName string, eventCount int32) ( []types.OutputLogEvent, error) { var events []types.OutputLogEvent logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName) output, err := actor.CwlClient.GetLogEvents(context.TODO(), &cloudwatchlogs.GetLogEventsInput{ LogStreamName: aws.String(logStreamName), Limit: aws.Int32(eventCount), LogGroupName: aws.String(logGroupName), }) if err != nil { log.Printf("Couldn't get log event for log stream %v. Here's why: %v\n", logStreamName, err) } else { events = output.Events } return events, err }

AWS CloudFormation アクションをラップする構造体を作成します。

// StackOutputs defines a map of outputs from a specific stack. type StackOutputs map[string]string type CloudFormationActions struct { CfnClient *cloudformation.Client } // GetOutputs gets the outputs from a CloudFormation stack and puts them into a structured format. func (actor CloudFormationActions) GetOutputs(stackName string) StackOutputs { output, err := actor.CfnClient.DescribeStacks(context.TODO(), &cloudformation.DescribeStacksInput{ StackName: aws.String(stackName), }) if err != nil || len(output.Stacks) == 0 { log.Panicf("Couldn't find a CloudFormation stack named %v. Here's why: %v\n", stackName, err) } stackOutputs := StackOutputs{} for _, out := range output.Stacks[0].Outputs { stackOutputs[*out.OutputKey] = *out.OutputValue } return stackOutputs }

リソースをクリーンアップします。

// Resources keeps track of AWS resources created during an example and handles // cleanup when the example finishes. type Resources struct { userPoolId string userAccessTokens []string triggers []actions.Trigger cognitoActor *actions.CognitoActions questioner demotools.IQuestioner } func (resources *Resources) init(cognitoActor *actions.CognitoActions, questioner demotools.IQuestioner) { resources.userAccessTokens = []string{} resources.triggers = []actions.Trigger{} resources.cognitoActor = cognitoActor resources.questioner = questioner } // Cleanup deletes all AWS resources created during an example. func (resources *Resources) Cleanup() { defer func() { if r := recover(); r != nil { log.Printf("Something went wrong during cleanup.\n%v\n", r) log.Println("Use the AWS Management Console to remove any remaining resources \n" + "that were created for this scenario.") } }() wantDelete := resources.questioner.AskBool("Do you want to remove all of the AWS resources that were created "+ "during this demo (y/n)?", "y") if wantDelete { for _, accessToken := range resources.userAccessTokens { err := resources.cognitoActor.DeleteUser(accessToken) if err != nil { log.Println("Couldn't delete user during cleanup.") panic(err) } log.Println("Deleted user.") } triggerList := make([]actions.TriggerInfo, len(resources.triggers)) for i := 0; i < len(resources.triggers); i++ { triggerList[i] = actions.TriggerInfo{Trigger: resources.triggers[i], HandlerArn: nil} } err := resources.cognitoActor.UpdateTriggers(resources.userPoolId, triggerList...) if err != nil { log.Println("Couldn't update Cognito triggers during cleanup.") panic(err) } log.Println("Removed Cognito triggers from user pool.") } else { log.Println("Be sure to remove resources when you're done with them to avoid unexpected charges!") } }

次のコード例は、Lambda 関数を使用して既知の Amazon Cognito ユーザーを自動的に移行する方法を示しています。

  • MigrateUser トリガーの Lambda 関数を呼び出すようにユーザープールを設定します。

  • ユーザープールにないユーザー名とパスワードを使用して Amazon Cognito にサインインします。

  • Lambda 関数は DynamoDB テーブルをスキャンし、既知のユーザーをユーザープールに自動的に移行します。

  • パスワードを忘れた場合のフローを実行して、移行したユーザーのパスワードをリセットします。

  • 新しいユーザーとしてサインインし、リソースをクリーンアップします。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

コマンドプロンプトからインタラクティブのシナリオを実行します。

import ( "errors" "fmt" "log" "strings" "user_pools_and_lambda_triggers/actions" "github.com/aws/aws-sdk-go-v2/aws" "github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider" "github.com/aws/aws-sdk-go-v2/service/cognitoidentityprovider/types" "github.com/awsdocs/aws-doc-sdk-examples/gov2/demotools" ) // MigrateUser separates the steps of this scenario into individual functions so that // they are simpler to read and understand. type MigrateUser struct { helper IScenarioHelper questioner demotools.IQuestioner resources Resources cognitoActor *actions.CognitoActions } // NewMigrateUser constructs a new migrate user runner. func NewMigrateUser(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) MigrateUser { scenario := MigrateUser{ helper: helper, questioner: questioner, resources: Resources{}, cognitoActor: &actions.CognitoActions{CognitoClient: cognitoidentityprovider.NewFromConfig(sdkConfig)}, } scenario.resources.init(scenario.cognitoActor, questioner) return scenario } // AddMigrateUserTrigger adds a Lambda handler as an invocation target for the MigrateUser trigger. func (runner *MigrateUser) AddMigrateUserTrigger(userPoolId string, functionArn string) { log.Printf("Let's add a Lambda function to handle the MigrateUser trigger from Cognito.\n" + "This trigger happens when an unknown user signs in, and lets your function take action before Cognito\n" + "rejects the user.\n\n") err := runner.cognitoActor.UpdateTriggers( userPoolId, actions.TriggerInfo{Trigger: actions.UserMigration, HandlerArn: aws.String(functionArn)}) if err != nil { panic(err) } log.Printf("Lambda function %v added to user pool %v to handle the MigrateUser trigger.\n", functionArn, userPoolId) log.Println(strings.Repeat("-", 88)) } // SignInUser adds a new user to the known users table and signs that user in to Amazon Cognito. func (runner *MigrateUser) SignInUser(usersTable string, clientId string) (bool, actions.User) { log.Println("Let's sign in a user to your Cognito user pool. When the username and email matches an entry in the\n" + "DynamoDB known users table, the email is automatically verified and the user is migrated to the Cognito user pool.") user := actions.User{} user.UserName = runner.questioner.Ask("\nEnter a username:") user.UserEmail = runner.questioner.Ask("\nEnter an email that you own. This email will be used to confirm user migration\n" + "during this example:") runner.helper.AddKnownUser(usersTable, user) var err error var resetRequired *types.PasswordResetRequiredException var authResult *types.AuthenticationResultType signedIn := false for !signedIn && resetRequired == nil { log.Printf("Signing in to Cognito as user '%v'. The expected result is a PasswordResetRequiredException.\n\n", user.UserName) authResult, err = runner.cognitoActor.SignIn(clientId, user.UserName, "_") if err != nil { if errors.As(err, &resetRequired) { log.Printf("\nUser '%v' is not in the Cognito user pool but was found in the DynamoDB known users table.\n"+ "User migration is started and a password reset is required.", user.UserName) } else { panic(err) } } else { log.Printf("User '%v' successfully signed in. This is unexpected and probably means you have not\n"+ "cleaned up a previous run of this scenario, so the user exist in the Cognito user pool.\n"+ "You can continue this example and select to clean up resources, or manually remove\n"+ "the user from your user pool and try again.", user.UserName) runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, *authResult.AccessToken) signedIn = true } } log.Println(strings.Repeat("-", 88)) return resetRequired != nil, user } // ResetPassword starts a password recovery flow. func (runner *MigrateUser) ResetPassword(clientId string, user actions.User) { wantCode := runner.questioner.AskBool(fmt.Sprintf("In order to migrate the user to Cognito, you must be able to receive a confirmation\n"+ "code by email at %v. Do you want to send a code (y/n)?", user.UserEmail), "y") if !wantCode { log.Println("To complete this example and successfully migrate a user to Cognito, you must enter an email\n" + "you own that can receive a confirmation code.") return } codeDelivery, err := runner.cognitoActor.ForgotPassword(clientId, user.UserName) if err != nil { panic(err) } log.Printf("\nA confirmation code has been sent to %v.", *codeDelivery.Destination) code := runner.questioner.Ask("Check your email and enter it here:") confirmed := false password := runner.questioner.AskPassword("\nEnter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.\n"+ "(the password will not display as you type):", 8) for !confirmed { log.Printf("\nConfirming password reset for user '%v'.\n", user.UserName) err = runner.cognitoActor.ConfirmForgotPassword(clientId, code, user.UserName, password) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { password = runner.questioner.AskPassword("\nEnter another password:", 8) } else { panic(err) } } else { confirmed = true } } log.Printf("User '%v' successfully confirmed and migrated.\n", user.UserName) log.Println("Signing in with your username and password...") authResult, err := runner.cognitoActor.SignIn(clientId, user.UserName, password) if err != nil { panic(err) } log.Printf("Successfully signed in. Your access token starts with: %v...\n", (*authResult.AccessToken)[:10]) runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, *authResult.AccessToken) log.Println(strings.Repeat("-", 88)) } // Run runs the scenario. func (runner *MigrateUser) Run(stackName string) { defer func() { if r := recover(); r != nil { log.Println("Something went wrong with the demo.") runner.resources.Cleanup() } }() log.Println(strings.Repeat("-", 88)) log.Printf("Welcome\n") log.Println(strings.Repeat("-", 88)) stackOutputs, err := runner.helper.GetStackOutputs(stackName) if err != nil { panic(err) } runner.resources.userPoolId = stackOutputs["UserPoolId"] runner.AddMigrateUserTrigger(stackOutputs["UserPoolId"], stackOutputs["MigrateUserFunctionArn"]) runner.resources.triggers = append(runner.resources.triggers, actions.UserMigration) resetNeeded, user := runner.SignInUser(stackOutputs["TableName"], stackOutputs["UserPoolClientId"]) if resetNeeded { runner.helper.ListRecentLogEvents(stackOutputs["MigrateUserFunction"]) runner.ResetPassword(stackOutputs["UserPoolClientId"], user) } runner.resources.Cleanup() log.Println(strings.Repeat("-", 88)) log.Println("Thanks for watching!") log.Println(strings.Repeat("-", 88)) }

Lambda 関数を使用してMigrateUserトリガーを処理します。

const TABLE_NAME = "TABLE_NAME" // UserInfo defines structured user data that can be marshalled to a DynamoDB format. type UserInfo struct { UserName string `dynamodbav:"UserName"` UserEmail string `dynamodbav:"UserEmail"` } type handler struct { dynamoClient *dynamodb.Client } // HandleRequest handles the MigrateUser event by looking up a user in an Amazon DynamoDB table and // specifying whether they should be migrated to the user pool. func (h *handler) HandleRequest(ctx context.Context, event events.CognitoEventUserPoolsMigrateUser) (events.CognitoEventUserPoolsMigrateUser, error) { log.Printf("Received migrate trigger from %v for user '%v'", event.TriggerSource, event.UserName) if event.TriggerSource != "UserMigration_Authentication" { return event, nil } tableName := os.Getenv(TABLE_NAME) user := UserInfo{ UserName: event.UserName, } log.Printf("Looking up user '%v' in table %v.\n", user.UserName, tableName) filterEx := expression.Name("UserName").Equal(expression.Value(user.UserName)) expr, err := expression.NewBuilder().WithFilter(filterEx).Build() if err != nil { log.Printf("Error building expression to query for user '%v'.\n", user.UserName) return event, err } output, err := h.dynamoClient.Scan(ctx, &dynamodb.ScanInput{ TableName: aws.String(tableName), FilterExpression: expr.Filter(), ExpressionAttributeNames: expr.Names(), ExpressionAttributeValues: expr.Values(), }) if err != nil { log.Printf("Error looking up user '%v'.\n", user.UserName) return event, err } if output.Items == nil || len(output.Items) == 0 { log.Printf("User '%v' not found, not migrating user.\n", user.UserName) return event, err } var users []UserInfo err = attributevalue.UnmarshalListOfMaps(output.Items, &users) if err != nil { log.Printf("Couldn't unmarshal DynamoDB items. Here's why: %v\n", err) return event, err } user = users[0] log.Printf("UserName '%v' found with email %v. User is migrated and must reset password.\n", user.UserName, user.UserEmail) event.CognitoEventUserPoolsMigrateUserResponse.UserAttributes = map[string]string{ "email": user.UserEmail, "email_verified": "true", // email_verified is required for the forgot password flow. } event.CognitoEventUserPoolsMigrateUserResponse.FinalUserStatus = "RESET_REQUIRED" event.CognitoEventUserPoolsMigrateUserResponse.MessageAction = "SUPPRESS" return event, err } func main() { sdkConfig, err := config.LoadDefaultConfig(context.TODO()) if err != nil { log.Panicln(err) } h := handler{ dynamoClient: dynamodb.NewFromConfig(sdkConfig), } lambda.Start(h.HandleRequest) }

一般的なタスクを実行する構造体を作成します。

// IScenarioHelper defines common functions used by the workflows in this example. type IScenarioHelper interface { Pause(secs int) GetStackOutputs(stackName string) (actions.StackOutputs, error) PopulateUserTable(tableName string) GetKnownUsers(tableName string) (actions.UserList, error) AddKnownUser(tableName string, user actions.User) ListRecentLogEvents(functionName string) } // ScenarioHelper contains AWS wrapper structs used by the workflows in this example. type ScenarioHelper struct { questioner demotools.IQuestioner dynamoActor *actions.DynamoActions cfnActor *actions.CloudFormationActions cwlActor *actions.CloudWatchLogsActions isTestRun bool } // NewScenarioHelper constructs a new scenario helper. func NewScenarioHelper(sdkConfig aws.Config, questioner demotools.IQuestioner) ScenarioHelper { scenario := ScenarioHelper{ questioner: questioner, dynamoActor: &actions.DynamoActions{DynamoClient: dynamodb.NewFromConfig(sdkConfig)}, cfnActor: &actions.CloudFormationActions{CfnClient: cloudformation.NewFromConfig(sdkConfig)}, cwlActor: &actions.CloudWatchLogsActions{CwlClient: cloudwatchlogs.NewFromConfig(sdkConfig)}, } return scenario } // Pause waits for the specified number of seconds. func (helper ScenarioHelper) Pause(secs int) { if !helper.isTestRun { time.Sleep(time.Duration(secs) * time.Second) } } // GetStackOutputs gets the outputs from the specified CloudFormation stack in a structured format. func (helper ScenarioHelper) GetStackOutputs(stackName string) (actions.StackOutputs, error) { return helper.cfnActor.GetOutputs(stackName), nil } // PopulateUserTable fills the known user table with example data. func (helper ScenarioHelper) PopulateUserTable(tableName string) { log.Printf("First, let's add some users to the DynamoDB %v table we'll use for this example.\n", tableName) err := helper.dynamoActor.PopulateTable(tableName) if err != nil { panic(err) } } // GetKnownUsers gets the users from the known users table in a structured format. func (helper ScenarioHelper) GetKnownUsers(tableName string) (actions.UserList, error) { knownUsers, err := helper.dynamoActor.Scan(tableName) if err != nil { log.Printf("Couldn't get known users from table %v. Here's why: %v\n", tableName, err) } return knownUsers, err } // AddKnownUser adds a user to the known users table. func (helper ScenarioHelper) AddKnownUser(tableName string, user actions.User) { log.Printf("Adding user '%v' with email '%v' to the DynamoDB known users table...\n", user.UserName, user.UserEmail) err := helper.dynamoActor.AddUser(tableName, user) if err != nil { panic(err) } } // ListRecentLogEvents gets the most recent log stream and events for the specified Lambda function and displays them. func (helper ScenarioHelper) ListRecentLogEvents(functionName string) { log.Println("Waiting a few seconds to let Lambda write to CloudWatch Logs...") helper.Pause(10) log.Println("Okay, let's check the logs to find what's happened recently with your Lambda function.") logStream, err := helper.cwlActor.GetLatestLogStream(functionName) if err != nil { panic(err) } log.Printf("Getting some recent events from log stream %v\n", *logStream.LogStreamName) events, err := helper.cwlActor.GetLogEvents(functionName, *logStream.LogStreamName, 10) if err != nil { panic(err) } for _, event := range events { log.Printf("\t%v", *event.Message) } log.Println(strings.Repeat("-", 88)) }

Amazon Cognito アクションをラップする構造体を作成します。

type CognitoActions struct { CognitoClient *cognitoidentityprovider.Client } // Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger. type Trigger int const ( PreSignUp Trigger = iota UserMigration PostAuthentication ) type TriggerInfo struct { Trigger Trigger HandlerArn *string } // UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value, // it is removed from the user pool. func (actor CognitoActions) UpdateTriggers(userPoolId string, triggers ...TriggerInfo) error { output, err := actor.CognitoClient.DescribeUserPool(context.TODO(), &cognitoidentityprovider.DescribeUserPoolInput{ UserPoolId: aws.String(userPoolId), }) if err != nil { log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err) return err } lambdaConfig := output.UserPool.LambdaConfig for _, trigger := range triggers { switch trigger.Trigger { case PreSignUp: lambdaConfig.PreSignUp = trigger.HandlerArn case UserMigration: lambdaConfig.UserMigration = trigger.HandlerArn case PostAuthentication: lambdaConfig.PostAuthentication = trigger.HandlerArn } } _, err = actor.CognitoClient.UpdateUserPool(context.TODO(), &cognitoidentityprovider.UpdateUserPoolInput{ UserPoolId: aws.String(userPoolId), LambdaConfig: lambdaConfig, }) if err != nil { log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err) } return err } // SignUp signs up a user with Amazon Cognito. func (actor CognitoActions) SignUp(clientId string, userName string, password string, userEmail string) (bool, error) { confirmed := false output, err := actor.CognitoClient.SignUp(context.TODO(), &cognitoidentityprovider.SignUpInput{ ClientId: aws.String(clientId), Password: aws.String(password), Username: aws.String(userName), UserAttributes: []types.AttributeType{ {Name: aws.String("email"), Value: aws.String(userEmail)}, }, }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err) } } else { confirmed = output.UserConfirmed } return confirmed, err } // SignIn signs in a user to Amazon Cognito using a username and password authentication flow. func (actor CognitoActions) SignIn(clientId string, userName string, password string) (*types.AuthenticationResultType, error) { var authResult *types.AuthenticationResultType output, err := actor.CognitoClient.InitiateAuth(context.TODO(), &cognitoidentityprovider.InitiateAuthInput{ AuthFlow: "USER_PASSWORD_AUTH", ClientId: aws.String(clientId), AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password}, }) if err != nil { var resetRequired *types.PasswordResetRequiredException if errors.As(err, &resetRequired) { log.Println(*resetRequired.Message) } else { log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err) } } else { authResult = output.AuthenticationResult } return authResult, err } // ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code // to the user's configured notification destination, such as email. func (actor CognitoActions) ForgotPassword(clientId string, userName string) (*types.CodeDeliveryDetailsType, error) { output, err := actor.CognitoClient.ForgotPassword(context.TODO(), &cognitoidentityprovider.ForgotPasswordInput{ ClientId: aws.String(clientId), Username: aws.String(userName), }) if err != nil { log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err) } return output.CodeDeliveryDetails, err } // ConfirmForgotPassword confirms a user with a confirmation code and a new password. func (actor CognitoActions) ConfirmForgotPassword(clientId string, code string, userName string, password string) error { _, err := actor.CognitoClient.ConfirmForgotPassword(context.TODO(), &cognitoidentityprovider.ConfirmForgotPasswordInput{ ClientId: aws.String(clientId), ConfirmationCode: aws.String(code), Password: aws.String(password), Username: aws.String(userName), }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err) } } return err } // DeleteUser removes a user from the user pool. func (actor CognitoActions) DeleteUser(userAccessToken string) error { _, err := actor.CognitoClient.DeleteUser(context.TODO(), &cognitoidentityprovider.DeleteUserInput{ AccessToken: aws.String(userAccessToken), }) if err != nil { log.Printf("Couldn't delete user. Here's why: %v\n", err) } return err } // AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user // in a state that requires they enter a new password next time they sign in. func (actor CognitoActions) AdminCreateUser(userPoolId string, userName string, userEmail string) error { _, err := actor.CognitoClient.AdminCreateUser(context.TODO(), &cognitoidentityprovider.AdminCreateUserInput{ UserPoolId: aws.String(userPoolId), Username: aws.String(userName), MessageAction: types.MessageActionTypeSuppress, UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}}, }) if err != nil { var userExists *types.UsernameExistsException if errors.As(err, &userExists) { log.Printf("User %v already exists in the user pool.", userName) err = nil } else { log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err) } } return err } // AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a // temporary password. func (actor CognitoActions) AdminSetUserPassword(userPoolId string, userName string, password string) error { _, err := actor.CognitoClient.AdminSetUserPassword(context.TODO(), &cognitoidentityprovider.AdminSetUserPasswordInput{ Password: aws.String(password), UserPoolId: aws.String(userPoolId), Username: aws.String(userName), Permanent: true, }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err) } } return err }

DynamoDB アクションをラップする構造体を作成します。

// DynamoActions encapsulates the Amazon Simple Notification Service (Amazon SNS) actions // used in the examples. type DynamoActions struct { DynamoClient *dynamodb.Client } // User defines structured user data. type User struct { UserName string UserEmail string LastLogin *LoginInfo `dynamodbav:",omitempty"` } // LoginInfo defines structured custom login data. type LoginInfo struct { UserPoolId string ClientId string Time string } // UserList defines a list of users. type UserList struct { Users []User } // UserNameList returns the usernames contained in a UserList as a list of strings. func (users *UserList) UserNameList() []string { names := make([]string, len(users.Users)) for i := 0; i < len(users.Users); i++ { names[i] = users.Users[i].UserName } return names } // PopulateTable adds a set of test users to the table. func (actor DynamoActions) PopulateTable(tableName string) error { var err error var item map[string]types.AttributeValue var writeReqs []types.WriteRequest for i := 1; i < 4; i++ { item, err = attributevalue.MarshalMap(User{UserName: fmt.Sprintf("test_user_%v", i), UserEmail: fmt.Sprintf("test_email_%v@example.com", i)}) if err != nil { log.Printf("Couldn't marshall user into DynamoDB format. Here's why: %v\n", err) return err } writeReqs = append(writeReqs, types.WriteRequest{PutRequest: &types.PutRequest{Item: item}}) } _, err = actor.DynamoClient.BatchWriteItem(context.TODO(), &dynamodb.BatchWriteItemInput{ RequestItems: map[string][]types.WriteRequest{tableName: writeReqs}, }) if err != nil { log.Printf("Couldn't populate table %v with users. Here's why: %v\n", tableName, err) } return err } // Scan scans the table for all items. func (actor DynamoActions) Scan(tableName string) (UserList, error) { var userList UserList output, err := actor.DynamoClient.Scan(context.TODO(), &dynamodb.ScanInput{ TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't scan table %v for items. Here's why: %v\n", tableName, err) } else { err = attributevalue.UnmarshalListOfMaps(output.Items, &userList.Users) if err != nil { log.Printf("Couldn't unmarshal items into users. Here's why: %v\n", err) } } return userList, err } // AddUser adds a user item to a table. func (actor DynamoActions) AddUser(tableName string, user User) error { userItem, err := attributevalue.MarshalMap(user) if err != nil { log.Printf("Couldn't marshall user to item. Here's why: %v\n", err) } _, err = actor.DynamoClient.PutItem(context.TODO(), &dynamodb.PutItemInput{ Item: userItem, TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't put item in table %v. Here's why: %v", tableName, err) } return err }

CloudWatch Logs アクションをラップする構造体を作成します。

type CloudWatchLogsActions struct { CwlClient *cloudwatchlogs.Client } // GetLatestLogStream gets the most recent log stream for a Lambda function. func (actor CloudWatchLogsActions) GetLatestLogStream(functionName string) (types.LogStream, error) { var logStream types.LogStream logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName) output, err := actor.CwlClient.DescribeLogStreams(context.TODO(), &cloudwatchlogs.DescribeLogStreamsInput{ Descending: aws.Bool(true), Limit: aws.Int32(1), LogGroupName: aws.String(logGroupName), OrderBy: types.OrderByLastEventTime, }) if err != nil { log.Printf("Couldn't get log streams for log group %v. Here's why: %v\n", logGroupName, err) } else { logStream = output.LogStreams[0] } return logStream, err } // GetLogEvents gets the most recent eventCount events from the specified log stream. func (actor CloudWatchLogsActions) GetLogEvents(functionName string, logStreamName string, eventCount int32) ( []types.OutputLogEvent, error) { var events []types.OutputLogEvent logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName) output, err := actor.CwlClient.GetLogEvents(context.TODO(), &cloudwatchlogs.GetLogEventsInput{ LogStreamName: aws.String(logStreamName), Limit: aws.Int32(eventCount), LogGroupName: aws.String(logGroupName), }) if err != nil { log.Printf("Couldn't get log event for log stream %v. Here's why: %v\n", logStreamName, err) } else { events = output.Events } return events, err }

AWS CloudFormation アクションをラップする構造体を作成します。

// StackOutputs defines a map of outputs from a specific stack. type StackOutputs map[string]string type CloudFormationActions struct { CfnClient *cloudformation.Client } // GetOutputs gets the outputs from a CloudFormation stack and puts them into a structured format. func (actor CloudFormationActions) GetOutputs(stackName string) StackOutputs { output, err := actor.CfnClient.DescribeStacks(context.TODO(), &cloudformation.DescribeStacksInput{ StackName: aws.String(stackName), }) if err != nil || len(output.Stacks) == 0 { log.Panicf("Couldn't find a CloudFormation stack named %v. Here's why: %v\n", stackName, err) } stackOutputs := StackOutputs{} for _, out := range output.Stacks[0].Outputs { stackOutputs[*out.OutputKey] = *out.OutputValue } return stackOutputs }

リソースをクリーンアップします。

// Resources keeps track of AWS resources created during an example and handles // cleanup when the example finishes. type Resources struct { userPoolId string userAccessTokens []string triggers []actions.Trigger cognitoActor *actions.CognitoActions questioner demotools.IQuestioner } func (resources *Resources) init(cognitoActor *actions.CognitoActions, questioner demotools.IQuestioner) { resources.userAccessTokens = []string{} resources.triggers = []actions.Trigger{} resources.cognitoActor = cognitoActor resources.questioner = questioner } // Cleanup deletes all AWS resources created during an example. func (resources *Resources) Cleanup() { defer func() { if r := recover(); r != nil { log.Printf("Something went wrong during cleanup.\n%v\n", r) log.Println("Use the AWS Management Console to remove any remaining resources \n" + "that were created for this scenario.") } }() wantDelete := resources.questioner.AskBool("Do you want to remove all of the AWS resources that were created "+ "during this demo (y/n)?", "y") if wantDelete { for _, accessToken := range resources.userAccessTokens { err := resources.cognitoActor.DeleteUser(accessToken) if err != nil { log.Println("Couldn't delete user during cleanup.") panic(err) } log.Println("Deleted user.") } triggerList := make([]actions.TriggerInfo, len(resources.triggers)) for i := 0; i < len(resources.triggers); i++ { triggerList[i] = actions.TriggerInfo{Trigger: resources.triggers[i], HandlerArn: nil} } err := resources.cognitoActor.UpdateTriggers(resources.userPoolId, triggerList...) if err != nil { log.Println("Couldn't update Cognito triggers during cleanup.") panic(err) } log.Println("Removed Cognito triggers from user pool.") } else { log.Println("Be sure to remove resources when you're done with them to avoid unexpected charges!") } }

次のコードサンプルは、以下の操作方法を示しています。

  • IAM ロールと Lambda 関数を作成し、ハンドラーコードをアップロードします。

  • 1 つのパラメーターで関数を呼び出して、結果を取得します。

  • 関数コードを更新し、環境変数で設定します。

  • 新しいパラメーターで関数を呼び出して、結果を取得します。返された実行ログを表示します。

  • アカウントの関数を一覧表示し、リソースをクリーンアップします。

詳細については、「コンソールで Lambda 関数を作成する」を参照してください。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

Lambda 関数の開始方法を示すインタラクティブなシナリオを作成します。

// GetStartedFunctionsScenario shows you how to use AWS Lambda to perform the following // actions: // // 1. Create an AWS Identity and Access Management (IAM) role and Lambda function, then upload handler code. // 2. Invoke the function with a single parameter and get results. // 3. Update the function code and configure with an environment variable. // 4. Invoke the function with new parameters and get results. Display the returned execution log. // 5. List the functions for your account, then clean up resources. type GetStartedFunctionsScenario struct { sdkConfig aws.Config functionWrapper actions.FunctionWrapper questioner demotools.IQuestioner helper IScenarioHelper isTestRun bool } // NewGetStartedFunctionsScenario constructs a GetStartedFunctionsScenario instance from a configuration. // It uses the specified config to get a Lambda client and create wrappers for the actions // used in the scenario. func NewGetStartedFunctionsScenario(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) GetStartedFunctionsScenario { lambdaClient := lambda.NewFromConfig(sdkConfig) return GetStartedFunctionsScenario{ sdkConfig: sdkConfig, functionWrapper: actions.FunctionWrapper{LambdaClient: lambdaClient}, questioner: questioner, helper: helper, } } // Run runs the interactive scenario. func (scenario GetStartedFunctionsScenario) Run() { defer func() { if r := recover(); r != nil { log.Printf("Something went wrong with the demo.\n") } }() log.Println(strings.Repeat("-", 88)) log.Println("Welcome to the AWS Lambda get started with functions demo.") log.Println(strings.Repeat("-", 88)) role := scenario.GetOrCreateRole() funcName := scenario.CreateFunction(role) scenario.InvokeIncrement(funcName) scenario.UpdateFunction(funcName) scenario.InvokeCalculator(funcName) scenario.ListFunctions() scenario.Cleanup(role, funcName) log.Println(strings.Repeat("-", 88)) log.Println("Thanks for watching!") log.Println(strings.Repeat("-", 88)) } // GetOrCreateRole checks whether the specified role exists and returns it if it does. // Otherwise, a role is created that specifies Lambda as a trusted principal. // The AWSLambdaBasicExecutionRole managed policy is attached to the role and the role // is returned. func (scenario GetStartedFunctionsScenario) GetOrCreateRole() *iamtypes.Role { var role *iamtypes.Role iamClient := iam.NewFromConfig(scenario.sdkConfig) log.Println("First, we need an IAM role that Lambda can assume.") roleName := scenario.questioner.Ask("Enter a name for the role:", demotools.NotEmpty{}) getOutput, err := iamClient.GetRole(context.TODO(), &iam.GetRoleInput{ RoleName: aws.String(roleName)}) if err != nil { var noSuch *iamtypes.NoSuchEntityException if errors.As(err, &noSuch) { log.Printf("Role %v doesn't exist. Creating it....\n", roleName) } else { log.Panicf("Couldn't check whether role %v exists. Here's why: %v\n", roleName, err) } } else { role = getOutput.Role log.Printf("Found role %v.\n", *role.RoleName) } if role == nil { trustPolicy := PolicyDocument{ Version: "2012-10-17", Statement: []PolicyStatement{{ Effect: "Allow", Principal: map[string]string{"Service": "lambda.amazonaws.com"}, Action: []string{"sts:AssumeRole"}, }}, } policyArn := "arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole" createOutput, err := iamClient.CreateRole(context.TODO(), &iam.CreateRoleInput{ AssumeRolePolicyDocument: aws.String(trustPolicy.String()), RoleName: aws.String(roleName), }) if err != nil { log.Panicf("Couldn't create role %v. Here's why: %v\n", roleName, err) } role = createOutput.Role _, err = iamClient.AttachRolePolicy(context.TODO(), &iam.AttachRolePolicyInput{ PolicyArn: aws.String(policyArn), RoleName: aws.String(roleName), }) if err != nil { log.Panicf("Couldn't attach a policy to role %v. Here's why: %v\n", roleName, err) } log.Printf("Created role %v.\n", *role.RoleName) log.Println("Let's give AWS a few seconds to propagate resources...") scenario.helper.Pause(10) } log.Println(strings.Repeat("-", 88)) return role } // CreateFunction creates a Lambda function and uploads a handler written in Python. // The code for the Python handler is packaged as a []byte in .zip format. func (scenario GetStartedFunctionsScenario) CreateFunction(role *iamtypes.Role) string { log.Println("Let's create a function that increments a number.\n" + "The function uses the 'lambda_handler_basic.py' script found in the \n" + "'handlers' directory of this project.") funcName := scenario.questioner.Ask("Enter a name for the Lambda function:", demotools.NotEmpty{}) zipPackage := scenario.helper.CreateDeploymentPackage("lambda_handler_basic.py", fmt.Sprintf("%v.py", funcName)) log.Printf("Creating function %v and waiting for it to be ready.", funcName) funcState := scenario.functionWrapper.CreateFunction(funcName, fmt.Sprintf("%v.lambda_handler", funcName), role.Arn, zipPackage) log.Printf("Your function is %v.", funcState) log.Println(strings.Repeat("-", 88)) return funcName } // InvokeIncrement invokes a Lambda function that increments a number. The function // parameters are contained in a Go struct that is used to serialize the parameters to // a JSON payload that is passed to the function. // The result payload is deserialized into a Go struct that contains an int value. func (scenario GetStartedFunctionsScenario) InvokeIncrement(funcName string) { parameters := actions.IncrementParameters{Action: "increment"} log.Println("Let's invoke our function. This function increments a number.") parameters.Number = scenario.questioner.AskInt("Enter a number to increment:", demotools.NotEmpty{}) log.Printf("Invoking %v with %v...\n", funcName, parameters.Number) invokeOutput := scenario.functionWrapper.Invoke(funcName, parameters, false) var payload actions.LambdaResultInt err := json.Unmarshal(invokeOutput.Payload, &payload) if err != nil { log.Panicf("Couldn't unmarshal payload from invoking %v. Here's why: %v\n", funcName, err) } log.Printf("Invoking %v with %v returned %v.\n", funcName, parameters.Number, payload) log.Println(strings.Repeat("-", 88)) } // UpdateFunction updates the code for a Lambda function by uploading a simple arithmetic // calculator written in Python. The code for the Python handler is packaged as a // []byte in .zip format. // After the code is updated, the configuration is also updated with a new log // level that instructs the handler to log additional information. func (scenario GetStartedFunctionsScenario) UpdateFunction(funcName string) { log.Println("Let's update the function to an arithmetic calculator.\n" + "The function uses the 'lambda_handler_calculator.py' script found in the \n" + "'handlers' directory of this project.") scenario.questioner.Ask("Press Enter when you're ready.") log.Println("Creating deployment package...") zipPackage := scenario.helper.CreateDeploymentPackage("lambda_handler_calculator.py", fmt.Sprintf("%v.py", funcName)) log.Println("...and updating the Lambda function and waiting for it to be ready.") funcState := scenario.functionWrapper.UpdateFunctionCode(funcName, zipPackage) log.Printf("Updated function %v. Its current state is %v.", funcName, funcState) log.Println("This function uses an environment variable to control logging level.") log.Println("Let's set it to DEBUG to get the most logging.") scenario.functionWrapper.UpdateFunctionConfiguration(funcName, map[string]string{"LOG_LEVEL": "DEBUG"}) log.Println(strings.Repeat("-", 88)) } // InvokeCalculator invokes the Lambda calculator function. The parameters are stored in a // Go struct that is used to serialize the parameters to a JSON payload. That payload is then passed // to the function. // The result payload is deserialized to a Go struct that stores the result as either an // int or float32, depending on the kind of operation that was specified. func (scenario GetStartedFunctionsScenario) InvokeCalculator(funcName string) { wantInvoke := true choices := []string{"plus", "minus", "times", "divided-by"} for wantInvoke { choice := scenario.questioner.AskChoice("Select an arithmetic operation:\n", choices) x := scenario.questioner.AskInt("Enter a value for x:", demotools.NotEmpty{}) y := scenario.questioner.AskInt("Enter a value for y:", demotools.NotEmpty{}) log.Printf("Invoking %v %v %v...", x, choices[choice], y) calcParameters := actions.CalculatorParameters{ Action: choices[choice], X: x, Y: y, } invokeOutput := scenario.functionWrapper.Invoke(funcName, calcParameters, true) var payload any if choice == 3 { // divide-by results in a float. payload = actions.LambdaResultFloat{} } else { payload = actions.LambdaResultInt{} } err := json.Unmarshal(invokeOutput.Payload, &payload) if err != nil { log.Panicf("Couldn't unmarshal payload from invoking %v. Here's why: %v\n", funcName, err) } log.Printf("Invoking %v with %v %v %v returned %v.\n", funcName, calcParameters.X, calcParameters.Action, calcParameters.Y, payload) scenario.questioner.Ask("Press Enter to see the logs from the call.") logRes, err := base64.StdEncoding.DecodeString(*invokeOutput.LogResult) if err != nil { log.Panicf("Couldn't decode log result. Here's why: %v\n", err) } log.Println(string(logRes)) wantInvoke = scenario.questioner.AskBool("Do you want to calculate again? (y/n)", "y") } log.Println(strings.Repeat("-", 88)) } // ListFunctions lists up to the specified number of functions for your account. func (scenario GetStartedFunctionsScenario) ListFunctions() { count := scenario.questioner.AskInt( "Let's list functions for your account. How many do you want to see?", demotools.NotEmpty{}) functions := scenario.functionWrapper.ListFunctions(count) log.Printf("Found %v functions:", len(functions)) for _, function := range functions { log.Printf("\t%v", *function.FunctionName) } log.Println(strings.Repeat("-", 88)) } // Cleanup removes the IAM and Lambda resources created by the example. func (scenario GetStartedFunctionsScenario) Cleanup(role *iamtypes.Role, funcName string) { if scenario.questioner.AskBool("Do you want to clean up resources created for this example? (y/n)", "y") { iamClient := iam.NewFromConfig(scenario.sdkConfig) policiesOutput, err := iamClient.ListAttachedRolePolicies(context.TODO(), &iam.ListAttachedRolePoliciesInput{RoleName: role.RoleName}) if err != nil { log.Panicf("Couldn't get policies attached to role %v. Here's why: %v\n", *role.RoleName, err) } for _, policy := range policiesOutput.AttachedPolicies { _, err = iamClient.DetachRolePolicy(context.TODO(), &iam.DetachRolePolicyInput{ PolicyArn: policy.PolicyArn, RoleName: role.RoleName, }) if err != nil { log.Panicf("Couldn't detach policy %v from role %v. Here's why: %v\n", *policy.PolicyArn, *role.RoleName, err) } } _, err = iamClient.DeleteRole(context.TODO(), &iam.DeleteRoleInput{RoleName: role.RoleName}) if err != nil { log.Panicf("Couldn't delete role %v. Here's why: %v\n", *role.RoleName, err) } log.Printf("Deleted role %v.\n", *role.RoleName) scenario.functionWrapper.DeleteFunction(funcName) log.Printf("Deleted function %v.\n", funcName) } else { log.Println("Okay. Don't forget to delete the resources when you're done with them.") } }

個別の Lambda アクションをラップする構造体を作成します。

// FunctionWrapper encapsulates function actions used in the examples. // It contains an AWS Lambda service client that is used to perform user actions. type FunctionWrapper struct { LambdaClient *lambda.Client } // GetFunction gets data about the Lambda function specified by functionName. func (wrapper FunctionWrapper) GetFunction(functionName string) types.State { var state types.State funcOutput, err := wrapper.LambdaClient.GetFunction(context.TODO(), &lambda.GetFunctionInput{ FunctionName: aws.String(functionName), }) if err != nil { log.Panicf("Couldn't get function %v. Here's why: %v\n", functionName, err) } else { state = funcOutput.Configuration.State } return state } // CreateFunction creates a new Lambda function from code contained in the zipPackage // buffer. The specified handlerName must match the name of the file and function // contained in the uploaded code. The role specified by iamRoleArn is assumed by // Lambda and grants specific permissions. // When the function already exists, types.StateActive is returned. // When the function is created, a lambda.FunctionActiveV2Waiter is used to wait until the // function is active. func (wrapper FunctionWrapper) CreateFunction(functionName string, handlerName string, iamRoleArn *string, zipPackage *bytes.Buffer) types.State { var state types.State _, err := wrapper.LambdaClient.CreateFunction(context.TODO(), &lambda.CreateFunctionInput{ Code: &types.FunctionCode{ZipFile: zipPackage.Bytes()}, FunctionName: aws.String(functionName), Role: iamRoleArn, Handler: aws.String(handlerName), Publish: true, Runtime: types.RuntimePython38, }) if err != nil { var resConflict *types.ResourceConflictException if errors.As(err, &resConflict) { log.Printf("Function %v already exists.\n", functionName) state = types.StateActive } else { log.Panicf("Couldn't create function %v. Here's why: %v\n", functionName, err) } } else { waiter := lambda.NewFunctionActiveV2Waiter(wrapper.LambdaClient) funcOutput, err := waiter.WaitForOutput(context.TODO(), &lambda.GetFunctionInput{ FunctionName: aws.String(functionName)}, 1*time.Minute) if err != nil { log.Panicf("Couldn't wait for function %v to be active. Here's why: %v\n", functionName, err) } else { state = funcOutput.Configuration.State } } return state } // UpdateFunctionCode updates the code for the Lambda function specified by functionName. // The existing code for the Lambda function is entirely replaced by the code in the // zipPackage buffer. After the update action is called, a lambda.FunctionUpdatedV2Waiter // is used to wait until the update is successful. func (wrapper FunctionWrapper) UpdateFunctionCode(functionName string, zipPackage *bytes.Buffer) types.State { var state types.State _, err := wrapper.LambdaClient.UpdateFunctionCode(context.TODO(), &lambda.UpdateFunctionCodeInput{ FunctionName: aws.String(functionName), ZipFile: zipPackage.Bytes(), }) if err != nil { log.Panicf("Couldn't update code for function %v. Here's why: %v\n", functionName, err) } else { waiter := lambda.NewFunctionUpdatedV2Waiter(wrapper.LambdaClient) funcOutput, err := waiter.WaitForOutput(context.TODO(), &lambda.GetFunctionInput{ FunctionName: aws.String(functionName)}, 1*time.Minute) if err != nil { log.Panicf("Couldn't wait for function %v to be active. Here's why: %v\n", functionName, err) } else { state = funcOutput.Configuration.State } } return state } // UpdateFunctionConfiguration updates a map of environment variables configured for // the Lambda function specified by functionName. func (wrapper FunctionWrapper) UpdateFunctionConfiguration(functionName string, envVars map[string]string) { _, err := wrapper.LambdaClient.UpdateFunctionConfiguration(context.TODO(), &lambda.UpdateFunctionConfigurationInput{ FunctionName: aws.String(functionName), Environment: &types.Environment{Variables: envVars}, }) if err != nil { log.Panicf("Couldn't update configuration for %v. Here's why: %v", functionName, err) } } // ListFunctions lists up to maxItems functions for the account. This function uses a // lambda.ListFunctionsPaginator to paginate the results. func (wrapper FunctionWrapper) ListFunctions(maxItems int) []types.FunctionConfiguration { var functions []types.FunctionConfiguration paginator := lambda.NewListFunctionsPaginator(wrapper.LambdaClient, &lambda.ListFunctionsInput{ MaxItems: aws.Int32(int32(maxItems)), }) for paginator.HasMorePages() && len(functions) < maxItems { pageOutput, err := paginator.NextPage(context.TODO()) if err != nil { log.Panicf("Couldn't list functions for your account. Here's why: %v\n", err) } functions = append(functions, pageOutput.Functions...) } return functions } // DeleteFunction deletes the Lambda function specified by functionName. func (wrapper FunctionWrapper) DeleteFunction(functionName string) { _, err := wrapper.LambdaClient.DeleteFunction(context.TODO(), &lambda.DeleteFunctionInput{ FunctionName: aws.String(functionName), }) if err != nil { log.Panicf("Couldn't delete function %v. Here's why: %v\n", functionName, err) } } // Invoke invokes the Lambda function specified by functionName, passing the parameters // as a JSON payload. When getLog is true, types.LogTypeTail is specified, which tells // Lambda to include the last few log lines in the returned result. func (wrapper FunctionWrapper) Invoke(functionName string, parameters any, getLog bool) *lambda.InvokeOutput { logType := types.LogTypeNone if getLog { logType = types.LogTypeTail } payload, err := json.Marshal(parameters) if err != nil { log.Panicf("Couldn't marshal parameters to JSON. Here's why %v\n", err) } invokeOutput, err := wrapper.LambdaClient.Invoke(context.TODO(), &lambda.InvokeInput{ FunctionName: aws.String(functionName), LogType: logType, Payload: payload, }) if err != nil { log.Panicf("Couldn't invoke function %v. Here's why: %v\n", functionName, err) } return invokeOutput } // IncrementParameters is used to serialize parameters to the increment Lambda handler. type IncrementParameters struct { Action string `json:"action"` Number int `json:"number"` } // CalculatorParameters is used to serialize parameters to the calculator Lambda handler. type CalculatorParameters struct { Action string `json:"action"` X int `json:"x"` Y int `json:"y"` } // LambdaResultInt is used to deserialize an int result from a Lambda handler. type LambdaResultInt struct { Result int `json:"result"` } // LambdaResultFloat is used to deserialize a float32 result from a Lambda handler. type LambdaResultFloat struct { Result float32 `json:"result"` }

シナリオの実行に役立つ関数を実装する構造体を作成します。

// IScenarioHelper abstracts I/O and wait functions from a scenario so that they // can be mocked for unit testing. type IScenarioHelper interface { Pause(secs int) CreateDeploymentPackage(sourceFile string, destinationFile string) *bytes.Buffer } // ScenarioHelper lets the caller specify the path to Lambda handler functions. type ScenarioHelper struct { HandlerPath string } // Pause waits for the specified number of seconds. func (helper *ScenarioHelper) Pause(secs int) { time.Sleep(time.Duration(secs) * time.Second) } // CreateDeploymentPackage creates an AWS Lambda deployment package from a source file. The // deployment package is stored in .zip format in a bytes.Buffer. The buffer can be // used to pass a []byte to Lambda when creating the function. // The specified destinationFile is the name to give the file when it's deployed to Lambda. func (helper *ScenarioHelper) CreateDeploymentPackage(sourceFile string, destinationFile string) *bytes.Buffer { var err error buffer := &bytes.Buffer{} writer := zip.NewWriter(buffer) zFile, err := writer.Create(destinationFile) if err != nil { log.Panicf("Couldn't create destination archive %v. Here's why: %v\n", destinationFile, err) } sourceBody, err := os.ReadFile(fmt.Sprintf("%v/%v", helper.HandlerPath, sourceFile)) if err != nil { log.Panicf("Couldn't read handler source file %v. Here's why: %v\n", sourceFile, err) } else { _, err = zFile.Write(sourceBody) if err != nil { log.Panicf("Couldn't write handler %v to zip archive. Here's why: %v\n", sourceFile, err) } } err = writer.Close() if err != nil { log.Panicf("Couldn't close zip writer. Here's why: %v\n", err) } return buffer }

数値をインクリメントする Lambda ハンドラーを定義します。

import logging logger = logging.getLogger() logger.setLevel(logging.INFO) def lambda_handler(event, context): """ Accepts an action and a single number, performs the specified action on the number, and returns the result. The only allowable action is 'increment'. :param event: The event dict that contains the parameters sent when the function is invoked. :param context: The context in which the function is called. :return: The result of the action. """ result = None action = event.get("action") if action == "increment": result = event.get("number", 0) + 1 logger.info("Calculated result of %s", result) else: logger.error("%s is not a valid action.", action) response = {"result": result} return response

算術演算を実行する 2 番目の Lambda ハンドラーを定義します。

import logging import os logger = logging.getLogger() # Define a list of Python lambda functions that are called by this AWS Lambda function. ACTIONS = { "plus": lambda x, y: x + y, "minus": lambda x, y: x - y, "times": lambda x, y: x * y, "divided-by": lambda x, y: x / y, } def lambda_handler(event, context): """ Accepts an action and two numbers, performs the specified action on the numbers, and returns the result. :param event: The event dict that contains the parameters sent when the function is invoked. :param context: The context in which the function is called. :return: The result of the specified action. """ # Set the log level based on a variable configured in the Lambda environment. logger.setLevel(os.environ.get("LOG_LEVEL", logging.INFO)) logger.debug("Event: %s", event) action = event.get("action") func = ACTIONS.get(action) x = event.get("x") y = event.get("y") result = None try: if func is not None and x is not None and y is not None: result = func(x, y) logger.info("%s %s %s is %s", x, action, y, result) else: logger.error("I can't calculate %s %s %s.", x, action, y) except ZeroDivisionError: logger.warning("I can't divide %s by 0!", x) response = {"result": result} return response

次のコード例は、Amazon Cognito ユーザー認証後に Lambda 関数を使用してカスタムアクティビティデータを書き込む方法を示しています。

  • 管理者機能を使用して、ユーザープールにユーザーを追加します。

  • PostAuthentication トリガーの Lambda 関数を呼び出すようにユーザープールを設定します。

  • 新しいユーザーを Amazon Cognito にサインインします。

  • Lambda 関数は、カスタム情報を CloudWatch Logs と DynamoDB テーブルに書き込みます。

  • DynamoDB テーブルからカスタムデータを取得して表示し、リソースをクリーンアップします。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。AWS コード例リポジトリ で全く同じ例を見つけて、設定と実行の方法を確認してください。

コマンドプロンプトからインタラクティブのシナリオを実行します。

// ActivityLog separates the steps of this scenario into individual functions so that // they are simpler to read and understand. type ActivityLog struct { helper IScenarioHelper questioner demotools.IQuestioner resources Resources cognitoActor *actions.CognitoActions } // NewActivityLog constructs a new activity log runner. func NewActivityLog(sdkConfig aws.Config, questioner demotools.IQuestioner, helper IScenarioHelper) ActivityLog { scenario := ActivityLog{ helper: helper, questioner: questioner, resources: Resources{}, cognitoActor: &actions.CognitoActions{CognitoClient: cognitoidentityprovider.NewFromConfig(sdkConfig)}, } scenario.resources.init(scenario.cognitoActor, questioner) return scenario } // AddUserToPool selects a user from the known users table and uses administrator credentials to add the user to the user pool. func (runner *ActivityLog) AddUserToPool(userPoolId string, tableName string) (string, string) { log.Println("To facilitate this example, let's add a user to the user pool using administrator privileges.") users, err := runner.helper.GetKnownUsers(tableName) if err != nil { panic(err) } user := users.Users[0] log.Printf("Adding known user %v to the user pool.\n", user.UserName) err = runner.cognitoActor.AdminCreateUser(userPoolId, user.UserName, user.UserEmail) if err != nil { panic(err) } pwSet := false password := runner.questioner.AskPassword("\nEnter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.\n"+ "(the password will not display as you type):", 8) for !pwSet { log.Printf("\nSetting password for user '%v'.\n", user.UserName) err = runner.cognitoActor.AdminSetUserPassword(userPoolId, user.UserName, password) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { password = runner.questioner.AskPassword("\nEnter another password:", 8) } else { panic(err) } } else { pwSet = true } } log.Println(strings.Repeat("-", 88)) return user.UserName, password } // AddActivityLogTrigger adds a Lambda handler as an invocation target for the PostAuthentication trigger. func (runner *ActivityLog) AddActivityLogTrigger(userPoolId string, activityLogArn string) { log.Println("Let's add a Lambda function to handle the PostAuthentication trigger from Cognito.\n" + "This trigger happens after a user is authenticated, and lets your function take action, such as logging\n" + "the outcome.") err := runner.cognitoActor.UpdateTriggers( userPoolId, actions.TriggerInfo{Trigger: actions.PostAuthentication, HandlerArn: aws.String(activityLogArn)}) if err != nil { panic(err) } runner.resources.triggers = append(runner.resources.triggers, actions.PostAuthentication) log.Printf("Lambda function %v added to user pool %v to handle PostAuthentication Cognito trigger.\n", activityLogArn, userPoolId) log.Println(strings.Repeat("-", 88)) } // SignInUser signs in as the specified user. func (runner *ActivityLog) SignInUser(clientId string, userName string, password string) { log.Printf("Now we'll sign in user %v and check the results in the logs and the DynamoDB table.", userName) runner.questioner.Ask("Press Enter when you're ready.") authResult, err := runner.cognitoActor.SignIn(clientId, userName, password) if err != nil { panic(err) } log.Println("Sign in successful.", "The PostAuthentication Lambda handler writes custom information to CloudWatch Logs.") runner.resources.userAccessTokens = append(runner.resources.userAccessTokens, *authResult.AccessToken) } // GetKnownUserLastLogin gets the login info for a user from the Amazon DynamoDB table and displays it. func (runner *ActivityLog) GetKnownUserLastLogin(tableName string, userName string) { log.Println("The PostAuthentication handler also writes login data to the DynamoDB table.") runner.questioner.Ask("Press Enter when you're ready to continue.") users, err := runner.helper.GetKnownUsers(tableName) if err != nil { panic(err) } for _, user := range users.Users { if user.UserName == userName { log.Println("The last login info for the user in the known users table is:") log.Printf("\t%+v", *user.LastLogin) } } log.Println(strings.Repeat("-", 88)) } // Run runs the scenario. func (runner *ActivityLog) Run(stackName string) { defer func() { if r := recover(); r != nil { log.Println("Something went wrong with the demo.") runner.resources.Cleanup() } }() log.Println(strings.Repeat("-", 88)) log.Printf("Welcome\n") log.Println(strings.Repeat("-", 88)) stackOutputs, err := runner.helper.GetStackOutputs(stackName) if err != nil { panic(err) } runner.resources.userPoolId = stackOutputs["UserPoolId"] runner.helper.PopulateUserTable(stackOutputs["TableName"]) userName, password := runner.AddUserToPool(stackOutputs["UserPoolId"], stackOutputs["TableName"]) runner.AddActivityLogTrigger(stackOutputs["UserPoolId"], stackOutputs["ActivityLogFunctionArn"]) runner.SignInUser(stackOutputs["UserPoolClientId"], userName, password) runner.helper.ListRecentLogEvents(stackOutputs["ActivityLogFunction"]) runner.GetKnownUserLastLogin(stackOutputs["TableName"], userName) runner.resources.Cleanup() log.Println(strings.Repeat("-", 88)) log.Println("Thanks for watching!") log.Println(strings.Repeat("-", 88)) }

Lambda 関数を使用してPostAuthenticationトリガーを処理します。

const TABLE_NAME = "TABLE_NAME" // LoginInfo defines structured login data that can be marshalled to a DynamoDB format. type LoginInfo struct { UserPoolId string `dynamodbav:"UserPoolId"` ClientId string `dynamodbav:"ClientId"` Time string `dynamodbav:"Time"` } // UserInfo defines structured user data that can be marshalled to a DynamoDB format. type UserInfo struct { UserName string `dynamodbav:"UserName"` UserEmail string `dynamodbav:"UserEmail"` LastLogin LoginInfo `dynamodbav:"LastLogin"` } // GetKey marshals the user email value to a DynamoDB key format. func (user UserInfo) GetKey() map[string]dynamodbtypes.AttributeValue { userEmail, err := attributevalue.Marshal(user.UserEmail) if err != nil { panic(err) } return map[string]dynamodbtypes.AttributeValue{"UserEmail": userEmail} } type handler struct { dynamoClient *dynamodb.Client } // HandleRequest handles the PostAuthentication event by writing custom data to the logs and // to an Amazon DynamoDB table. func (h *handler) HandleRequest(ctx context.Context, event events.CognitoEventUserPoolsPostAuthentication) (events.CognitoEventUserPoolsPostAuthentication, error) { log.Printf("Received post authentication trigger from %v for user '%v'", event.TriggerSource, event.UserName) tableName := os.Getenv(TABLE_NAME) user := UserInfo{ UserName: event.UserName, UserEmail: event.Request.UserAttributes["email"], LastLogin: LoginInfo{ UserPoolId: event.UserPoolID, ClientId: event.CallerContext.ClientID, Time: time.Now().Format(time.UnixDate), }, } // Write to CloudWatch Logs. fmt.Printf("%#v", user) // Also write to an external system. This examples uses DynamoDB to demonstrate. userMap, err := attributevalue.MarshalMap(user) if err != nil { log.Printf("Couldn't marshal to DynamoDB map. Here's why: %v\n", err) } else if len(userMap) == 0 { log.Printf("User info marshaled to an empty map.") } else { _, err := h.dynamoClient.PutItem(ctx, &dynamodb.PutItemInput{ Item: userMap, TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't write to DynamoDB. Here's why: %v\n", err) } else { log.Printf("Wrote user info to DynamoDB table %v.\n", tableName) } } return event, nil } func main() { sdkConfig, err := config.LoadDefaultConfig(context.TODO()) if err != nil { log.Panicln(err) } h := handler{ dynamoClient: dynamodb.NewFromConfig(sdkConfig), } lambda.Start(h.HandleRequest) }

一般的なタスクを実行する構造体を作成します。

// IScenarioHelper defines common functions used by the workflows in this example. type IScenarioHelper interface { Pause(secs int) GetStackOutputs(stackName string) (actions.StackOutputs, error) PopulateUserTable(tableName string) GetKnownUsers(tableName string) (actions.UserList, error) AddKnownUser(tableName string, user actions.User) ListRecentLogEvents(functionName string) } // ScenarioHelper contains AWS wrapper structs used by the workflows in this example. type ScenarioHelper struct { questioner demotools.IQuestioner dynamoActor *actions.DynamoActions cfnActor *actions.CloudFormationActions cwlActor *actions.CloudWatchLogsActions isTestRun bool } // NewScenarioHelper constructs a new scenario helper. func NewScenarioHelper(sdkConfig aws.Config, questioner demotools.IQuestioner) ScenarioHelper { scenario := ScenarioHelper{ questioner: questioner, dynamoActor: &actions.DynamoActions{DynamoClient: dynamodb.NewFromConfig(sdkConfig)}, cfnActor: &actions.CloudFormationActions{CfnClient: cloudformation.NewFromConfig(sdkConfig)}, cwlActor: &actions.CloudWatchLogsActions{CwlClient: cloudwatchlogs.NewFromConfig(sdkConfig)}, } return scenario } // Pause waits for the specified number of seconds. func (helper ScenarioHelper) Pause(secs int) { if !helper.isTestRun { time.Sleep(time.Duration(secs) * time.Second) } } // GetStackOutputs gets the outputs from the specified CloudFormation stack in a structured format. func (helper ScenarioHelper) GetStackOutputs(stackName string) (actions.StackOutputs, error) { return helper.cfnActor.GetOutputs(stackName), nil } // PopulateUserTable fills the known user table with example data. func (helper ScenarioHelper) PopulateUserTable(tableName string) { log.Printf("First, let's add some users to the DynamoDB %v table we'll use for this example.\n", tableName) err := helper.dynamoActor.PopulateTable(tableName) if err != nil { panic(err) } } // GetKnownUsers gets the users from the known users table in a structured format. func (helper ScenarioHelper) GetKnownUsers(tableName string) (actions.UserList, error) { knownUsers, err := helper.dynamoActor.Scan(tableName) if err != nil { log.Printf("Couldn't get known users from table %v. Here's why: %v\n", tableName, err) } return knownUsers, err } // AddKnownUser adds a user to the known users table. func (helper ScenarioHelper) AddKnownUser(tableName string, user actions.User) { log.Printf("Adding user '%v' with email '%v' to the DynamoDB known users table...\n", user.UserName, user.UserEmail) err := helper.dynamoActor.AddUser(tableName, user) if err != nil { panic(err) } } // ListRecentLogEvents gets the most recent log stream and events for the specified Lambda function and displays them. func (helper ScenarioHelper) ListRecentLogEvents(functionName string) { log.Println("Waiting a few seconds to let Lambda write to CloudWatch Logs...") helper.Pause(10) log.Println("Okay, let's check the logs to find what's happened recently with your Lambda function.") logStream, err := helper.cwlActor.GetLatestLogStream(functionName) if err != nil { panic(err) } log.Printf("Getting some recent events from log stream %v\n", *logStream.LogStreamName) events, err := helper.cwlActor.GetLogEvents(functionName, *logStream.LogStreamName, 10) if err != nil { panic(err) } for _, event := range events { log.Printf("\t%v", *event.Message) } log.Println(strings.Repeat("-", 88)) }

Amazon Cognito アクションをラップする構造体を作成します。

type CognitoActions struct { CognitoClient *cognitoidentityprovider.Client } // Trigger and TriggerInfo define typed data for updating an Amazon Cognito trigger. type Trigger int const ( PreSignUp Trigger = iota UserMigration PostAuthentication ) type TriggerInfo struct { Trigger Trigger HandlerArn *string } // UpdateTriggers adds or removes Lambda triggers for a user pool. When a trigger is specified with a `nil` value, // it is removed from the user pool. func (actor CognitoActions) UpdateTriggers(userPoolId string, triggers ...TriggerInfo) error { output, err := actor.CognitoClient.DescribeUserPool(context.TODO(), &cognitoidentityprovider.DescribeUserPoolInput{ UserPoolId: aws.String(userPoolId), }) if err != nil { log.Printf("Couldn't get info about user pool %v. Here's why: %v\n", userPoolId, err) return err } lambdaConfig := output.UserPool.LambdaConfig for _, trigger := range triggers { switch trigger.Trigger { case PreSignUp: lambdaConfig.PreSignUp = trigger.HandlerArn case UserMigration: lambdaConfig.UserMigration = trigger.HandlerArn case PostAuthentication: lambdaConfig.PostAuthentication = trigger.HandlerArn } } _, err = actor.CognitoClient.UpdateUserPool(context.TODO(), &cognitoidentityprovider.UpdateUserPoolInput{ UserPoolId: aws.String(userPoolId), LambdaConfig: lambdaConfig, }) if err != nil { log.Printf("Couldn't update user pool %v. Here's why: %v\n", userPoolId, err) } return err } // SignUp signs up a user with Amazon Cognito. func (actor CognitoActions) SignUp(clientId string, userName string, password string, userEmail string) (bool, error) { confirmed := false output, err := actor.CognitoClient.SignUp(context.TODO(), &cognitoidentityprovider.SignUpInput{ ClientId: aws.String(clientId), Password: aws.String(password), Username: aws.String(userName), UserAttributes: []types.AttributeType{ {Name: aws.String("email"), Value: aws.String(userEmail)}, }, }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't sign up user %v. Here's why: %v\n", userName, err) } } else { confirmed = output.UserConfirmed } return confirmed, err } // SignIn signs in a user to Amazon Cognito using a username and password authentication flow. func (actor CognitoActions) SignIn(clientId string, userName string, password string) (*types.AuthenticationResultType, error) { var authResult *types.AuthenticationResultType output, err := actor.CognitoClient.InitiateAuth(context.TODO(), &cognitoidentityprovider.InitiateAuthInput{ AuthFlow: "USER_PASSWORD_AUTH", ClientId: aws.String(clientId), AuthParameters: map[string]string{"USERNAME": userName, "PASSWORD": password}, }) if err != nil { var resetRequired *types.PasswordResetRequiredException if errors.As(err, &resetRequired) { log.Println(*resetRequired.Message) } else { log.Printf("Couldn't sign in user %v. Here's why: %v\n", userName, err) } } else { authResult = output.AuthenticationResult } return authResult, err } // ForgotPassword starts a password recovery flow for a user. This flow typically sends a confirmation code // to the user's configured notification destination, such as email. func (actor CognitoActions) ForgotPassword(clientId string, userName string) (*types.CodeDeliveryDetailsType, error) { output, err := actor.CognitoClient.ForgotPassword(context.TODO(), &cognitoidentityprovider.ForgotPasswordInput{ ClientId: aws.String(clientId), Username: aws.String(userName), }) if err != nil { log.Printf("Couldn't start password reset for user '%v'. Here;s why: %v\n", userName, err) } return output.CodeDeliveryDetails, err } // ConfirmForgotPassword confirms a user with a confirmation code and a new password. func (actor CognitoActions) ConfirmForgotPassword(clientId string, code string, userName string, password string) error { _, err := actor.CognitoClient.ConfirmForgotPassword(context.TODO(), &cognitoidentityprovider.ConfirmForgotPasswordInput{ ClientId: aws.String(clientId), ConfirmationCode: aws.String(code), Password: aws.String(password), Username: aws.String(userName), }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't confirm user %v. Here's why: %v", userName, err) } } return err } // DeleteUser removes a user from the user pool. func (actor CognitoActions) DeleteUser(userAccessToken string) error { _, err := actor.CognitoClient.DeleteUser(context.TODO(), &cognitoidentityprovider.DeleteUserInput{ AccessToken: aws.String(userAccessToken), }) if err != nil { log.Printf("Couldn't delete user. Here's why: %v\n", err) } return err } // AdminCreateUser uses administrator credentials to add a user to a user pool. This method leaves the user // in a state that requires they enter a new password next time they sign in. func (actor CognitoActions) AdminCreateUser(userPoolId string, userName string, userEmail string) error { _, err := actor.CognitoClient.AdminCreateUser(context.TODO(), &cognitoidentityprovider.AdminCreateUserInput{ UserPoolId: aws.String(userPoolId), Username: aws.String(userName), MessageAction: types.MessageActionTypeSuppress, UserAttributes: []types.AttributeType{{Name: aws.String("email"), Value: aws.String(userEmail)}}, }) if err != nil { var userExists *types.UsernameExistsException if errors.As(err, &userExists) { log.Printf("User %v already exists in the user pool.", userName) err = nil } else { log.Printf("Couldn't create user %v. Here's why: %v\n", userName, err) } } return err } // AdminSetUserPassword uses administrator credentials to set a password for a user without requiring a // temporary password. func (actor CognitoActions) AdminSetUserPassword(userPoolId string, userName string, password string) error { _, err := actor.CognitoClient.AdminSetUserPassword(context.TODO(), &cognitoidentityprovider.AdminSetUserPasswordInput{ Password: aws.String(password), UserPoolId: aws.String(userPoolId), Username: aws.String(userName), Permanent: true, }) if err != nil { var invalidPassword *types.InvalidPasswordException if errors.As(err, &invalidPassword) { log.Println(*invalidPassword.Message) } else { log.Printf("Couldn't set password for user %v. Here's why: %v\n", userName, err) } } return err }

DynamoDB アクションをラップする構造体を作成します。

// DynamoActions encapsulates the Amazon Simple Notification Service (Amazon SNS) actions // used in the examples. type DynamoActions struct { DynamoClient *dynamodb.Client } // User defines structured user data. type User struct { UserName string UserEmail string LastLogin *LoginInfo `dynamodbav:",omitempty"` } // LoginInfo defines structured custom login data. type LoginInfo struct { UserPoolId string ClientId string Time string } // UserList defines a list of users. type UserList struct { Users []User } // UserNameList returns the usernames contained in a UserList as a list of strings. func (users *UserList) UserNameList() []string { names := make([]string, len(users.Users)) for i := 0; i < len(users.Users); i++ { names[i] = users.Users[i].UserName } return names } // PopulateTable adds a set of test users to the table. func (actor DynamoActions) PopulateTable(tableName string) error { var err error var item map[string]types.AttributeValue var writeReqs []types.WriteRequest for i := 1; i < 4; i++ { item, err = attributevalue.MarshalMap(User{UserName: fmt.Sprintf("test_user_%v", i), UserEmail: fmt.Sprintf("test_email_%v@example.com", i)}) if err != nil { log.Printf("Couldn't marshall user into DynamoDB format. Here's why: %v\n", err) return err } writeReqs = append(writeReqs, types.WriteRequest{PutRequest: &types.PutRequest{Item: item}}) } _, err = actor.DynamoClient.BatchWriteItem(context.TODO(), &dynamodb.BatchWriteItemInput{ RequestItems: map[string][]types.WriteRequest{tableName: writeReqs}, }) if err != nil { log.Printf("Couldn't populate table %v with users. Here's why: %v\n", tableName, err) } return err } // Scan scans the table for all items. func (actor DynamoActions) Scan(tableName string) (UserList, error) { var userList UserList output, err := actor.DynamoClient.Scan(context.TODO(), &dynamodb.ScanInput{ TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't scan table %v for items. Here's why: %v\n", tableName, err) } else { err = attributevalue.UnmarshalListOfMaps(output.Items, &userList.Users) if err != nil { log.Printf("Couldn't unmarshal items into users. Here's why: %v\n", err) } } return userList, err } // AddUser adds a user item to a table. func (actor DynamoActions) AddUser(tableName string, user User) error { userItem, err := attributevalue.MarshalMap(user) if err != nil { log.Printf("Couldn't marshall user to item. Here's why: %v\n", err) } _, err = actor.DynamoClient.PutItem(context.TODO(), &dynamodb.PutItemInput{ Item: userItem, TableName: aws.String(tableName), }) if err != nil { log.Printf("Couldn't put item in table %v. Here's why: %v", tableName, err) } return err }

CloudWatch Logs アクションをラップする構造体を作成します。

type CloudWatchLogsActions struct { CwlClient *cloudwatchlogs.Client } // GetLatestLogStream gets the most recent log stream for a Lambda function. func (actor CloudWatchLogsActions) GetLatestLogStream(functionName string) (types.LogStream, error) { var logStream types.LogStream logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName) output, err := actor.CwlClient.DescribeLogStreams(context.TODO(), &cloudwatchlogs.DescribeLogStreamsInput{ Descending: aws.Bool(true), Limit: aws.Int32(1), LogGroupName: aws.String(logGroupName), OrderBy: types.OrderByLastEventTime, }) if err != nil { log.Printf("Couldn't get log streams for log group %v. Here's why: %v\n", logGroupName, err) } else { logStream = output.LogStreams[0] } return logStream, err } // GetLogEvents gets the most recent eventCount events from the specified log stream. func (actor CloudWatchLogsActions) GetLogEvents(functionName string, logStreamName string, eventCount int32) ( []types.OutputLogEvent, error) { var events []types.OutputLogEvent logGroupName := fmt.Sprintf("/aws/lambda/%s", functionName) output, err := actor.CwlClient.GetLogEvents(context.TODO(), &cloudwatchlogs.GetLogEventsInput{ LogStreamName: aws.String(logStreamName), Limit: aws.Int32(eventCount), LogGroupName: aws.String(logGroupName), }) if err != nil { log.Printf("Couldn't get log event for log stream %v. Here's why: %v\n", logStreamName, err) } else { events = output.Events } return events, err }

AWS CloudFormation アクションをラップする構造体を作成します。

// StackOutputs defines a map of outputs from a specific stack. type StackOutputs map[string]string type CloudFormationActions struct { CfnClient *cloudformation.Client } // GetOutputs gets the outputs from a CloudFormation stack and puts them into a structured format. func (actor CloudFormationActions) GetOutputs(stackName string) StackOutputs { output, err := actor.CfnClient.DescribeStacks(context.TODO(), &cloudformation.DescribeStacksInput{ StackName: aws.String(stackName), }) if err != nil || len(output.Stacks) == 0 { log.Panicf("Couldn't find a CloudFormation stack named %v. Here's why: %v\n", stackName, err) } stackOutputs := StackOutputs{} for _, out := range output.Stacks[0].Outputs { stackOutputs[*out.OutputKey] = *out.OutputValue } return stackOutputs }

リソースをクリーンアップします。

// Resources keeps track of AWS resources created during an example and handles // cleanup when the example finishes. type Resources struct { userPoolId string userAccessTokens []string triggers []actions.Trigger cognitoActor *actions.CognitoActions questioner demotools.IQuestioner } func (resources *Resources) init(cognitoActor *actions.CognitoActions, questioner demotools.IQuestioner) { resources.userAccessTokens = []string{} resources.triggers = []actions.Trigger{} resources.cognitoActor = cognitoActor resources.questioner = questioner } // Cleanup deletes all AWS resources created during an example. func (resources *Resources) Cleanup() { defer func() { if r := recover(); r != nil { log.Printf("Something went wrong during cleanup.\n%v\n", r) log.Println("Use the AWS Management Console to remove any remaining resources \n" + "that were created for this scenario.") } }() wantDelete := resources.questioner.AskBool("Do you want to remove all of the AWS resources that were created "+ "during this demo (y/n)?", "y") if wantDelete { for _, accessToken := range resources.userAccessTokens { err := resources.cognitoActor.DeleteUser(accessToken) if err != nil { log.Println("Couldn't delete user during cleanup.") panic(err) } log.Println("Deleted user.") } triggerList := make([]actions.TriggerInfo, len(resources.triggers)) for i := 0; i < len(resources.triggers); i++ { triggerList[i] = actions.TriggerInfo{Trigger: resources.triggers[i], HandlerArn: nil} } err := resources.cognitoActor.UpdateTriggers(resources.userPoolId, triggerList...) if err != nil { log.Println("Couldn't update Cognito triggers during cleanup.") panic(err) } log.Println("Removed Cognito triggers from user pool.") } else { log.Println("Be sure to remove resources when you're done with them to avoid unexpected charges!") } }

サーバーレスサンプル

次のコード例では、Kinesis ストリームからレコードを受信することによってトリガーされるイベントを受け取る、Lambda 関数の実装方法を示しています。この関数は Kinesis ペイロードを取得し、それを Base64 からデコードして、そのレコードの内容をログ記録します。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用した Lambda での Kinesis イベントの消費。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "log" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) func handler(ctx context.Context, kinesisEvent events.KinesisEvent) error { if len(kinesisEvent.Records) == 0 { log.Printf("empty Kinesis event received") return nil } for _, record := range kinesisEvent.Records { log.Printf("processed Kinesis event with EventId: %v", record.EventID) recordDataBytes := record.Kinesis.Data recordDataText := string(recordDataBytes) log.Printf("record data: %v", recordDataText) // TODO: Do interesting work based on the new data } log.Printf("successfully processed %v records", len(kinesisEvent.Records)) return nil } func main() { lambda.Start(handler) }

次のコード例は、DynamoDB ストリームからレコードを受信することによってトリガーされるイベントを受信する Lambda 関数を実装する方法を示しています。関数は DynamoDB ペイロードを取得し、レコードの内容をログ記録します。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用して Lambda で DynamoDB イベントの消費。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "github.com/aws/aws-lambda-go/lambda" "github.com/aws/aws-lambda-go/events" "fmt" ) func HandleRequest(ctx context.Context, event events.DynamoDBEvent) (*string, error) { if len(event.Records) == 0 { return nil, fmt.Errorf("received empty event") } for _, record := range event.Records { LogDynamoDBRecord(record) } message := fmt.Sprintf("Records processed: %d", len(event.Records)) return &message, nil } func main() { lambda.Start(HandleRequest) } func LogDynamoDBRecord(record events.DynamoDBEventRecord){ fmt.Println(record.EventID) fmt.Println(record.EventName) fmt.Printf("%+v\n", record.Change) }

次のコード例は、S3 バケットにオブジェクトをアップロードすることによってトリガーされるイベントを受け取る Lambda 関数を実装する方法を示しています。この関数は、イベントパラメータから S3 バケット名とオブジェクトキーを取得し、Amazon S3 API を呼び出してオブジェクトのコンテンツタイプを取得してログに記録します。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用して Lambda で S3 イベントを消費します。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "log" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" "github.com/aws/aws-sdk-go-v2/config" "github.com/aws/aws-sdk-go-v2/service/s3" ) func handler(ctx context.Context, s3Event events.S3Event) error { sdkConfig, err := config.LoadDefaultConfig(ctx) if err != nil { log.Printf("failed to load default config: %s", err) return err } s3Client := s3.NewFromConfig(sdkConfig) for _, record := range s3Event.Records { bucket := record.S3.Bucket.Name key := record.S3.Object.URLDecodedKey headOutput, err := s3Client.HeadObject(ctx, &s3.HeadObjectInput{ Bucket: &bucket, Key: &key, }) if err != nil { log.Printf("error getting head of object %s/%s: %s", bucket, key, err) return err } log.Printf("successfully retrieved %s/%s of type %s", bucket, key, *headOutput.ContentType) } return nil } func main() { lambda.Start(handler) }

次のコード例は、SNS トピックからメッセージを受信することによってトリガーされるイベントを受け取る Lambda 関数を実装する方法を示しています。この関数はイベントパラメータからメッセージを取得し、各メッセージの内容を記録します。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用して Lambda で SNS イベントを消費します。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "fmt" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) func handler(ctx context.Context, snsEvent events.SNSEvent) { for _, record := range snsEvent.Records { processMessage(record) } fmt.Println("done") } func processMessage(record events.SNSEventRecord) { message := record.SNS.Message fmt.Printf("Processed message: %s\n", message) // TODO: Process your record here } func main() { lambda.Start(handler) }

次のコード例では、SQS キューからメッセージを受信することによってトリガーされるイベントを受け取る、Lambda 関数の実装方法を示しています。この関数はイベントパラメータからメッセージを取得し、各メッセージの内容を記録します。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用した Lambda での SQS イベントの消費。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package integration_sqs_to_lambda import ( "fmt" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) func handler(event events.SQSEvent) error { for _, record := range event.Records { err := processMessage(record) if err != nil { return err } } fmt.Println("done") return nil } func processMessage(record events.SQSMessage) error { fmt.Printf("Processed message %s\n", record.Body) // TODO: Do interesting work based on the new message return nil } func main() { lambda.Start(handler) }

以下のコード例では、Kinesis ストリームからイベントを受け取る Lambda 関数のための、部分的なバッチレスポンスの実装方法を示しています。この関数は、レスポンスとしてバッチアイテムの失敗を報告し、対象のメッセージを後で再試行するよう Lambda に伝えます。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用した Lambda での Kinesis バッチアイテム失敗のレポート。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "fmt" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) func handler(ctx context.Context, kinesisEvent events.KinesisEvent) (map[string]interface{}, error) { batchItemFailures := []map[string]interface{}{} for _, record := range kinesisEvent.Records { curRecordSequenceNumber := "" // Process your record if /* Your record processing condition here */ { curRecordSequenceNumber = record.Kinesis.SequenceNumber } // Add a condition to check if the record processing failed if curRecordSequenceNumber != "" { batchItemFailures = append(batchItemFailures, map[string]interface{}{"itemIdentifier": curRecordSequenceNumber}) } } kinesisBatchResponse := map[string]interface{}{ "batchItemFailures": batchItemFailures, } return kinesisBatchResponse, nil } func main() { lambda.Start(handler) }

次のコード例は、DynamoDB ストリームからイベントを受信する Lambda 関数の部分的なバッチレスポンスを実装する方法を示しています。この関数は、レスポンスとしてバッチアイテムの失敗を報告し、対象のメッセージを後で再試行するよう Lambda に伝えます。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用して Lambda で DynamoDB のバッチアイテム失敗のレポート。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) type BatchItemFailure struct { ItemIdentifier string `json:"ItemIdentifier"` } type BatchResult struct { BatchItemFailures []BatchItemFailure `json:"BatchItemFailures"` } func HandleRequest(ctx context.Context, event events.DynamoDBEvent) (*BatchResult, error) { var batchItemFailures []BatchItemFailure curRecordSequenceNumber := "" for _, record := range event.Records { // Process your record curRecordSequenceNumber = record.Change.SequenceNumber } if curRecordSequenceNumber != "" { batchItemFailures = append(batchItemFailures, BatchItemFailure{ItemIdentifier: curRecordSequenceNumber}) } batchResult := BatchResult{ BatchItemFailures: batchItemFailures, } return &batchResult, nil } func main() { lambda.Start(HandleRequest) }

以下のコード例では、SQS キューからイベントを受け取る Lambda 関数のための、部分的なバッチレスポンスの実装方法を示しています。この関数は、レスポンスとしてバッチアイテムの失敗を報告し、対象のメッセージを後で再試行するよう Lambda に伝えます。

SDK for Go V2
注記

の詳細については、「」を参照してください GitHub。サーバーレスサンプルリポジトリで完全な例を検索し、設定および実行の方法を確認してください。

Go を使用した Lambda での SQS バッチアイテム失敗のレポート。

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 package main import ( "context" "encoding/json" "fmt" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) func handler(ctx context.Context, sqsEvent events.SQSEvent) (map[string]interface{}, error) { batchItemFailures := []map[string]interface{}{} for _, message := range sqsEvent.Records { if /* Your message processing condition here */ { batchItemFailures = append(batchItemFailures, map[string]interface{}{"itemIdentifier": message.MessageId}) } } sqsBatchResponse := map[string]interface{}{ "batchItemFailures": batchItemFailures, } return sqsBatchResponse, nil } func main() { lambda.Start(handler) }