AWS Lambda
Developer Guide


Publishes a version of your function from the current snapshot of $LATEST. That is, AWS Lambda takes a snapshot of the function code and configuration information from $LATEST and publishes a new version. The code and configuration cannot be modified after publication. For information about the versioning feature, see AWS Lambda Function Versioning and Aliases.

Request Syntax

POST /2015-03-31/functions/FunctionName/versions HTTP/1.1 Content-type: application/json { "CodeSha256": "string", "Description": "string", "RevisionId": "string" }

URI Request Parameters

The request requires the following URI parameters.


The name of the lambda function.

Name formats

  • Function name - MyFunction.

  • Function ARN - arn:aws:lambda:us-west-2:123456789012:function:MyFunction.

  • Partial ARN - 123456789012:function:MyFunction.

The length constraint applies only to the full ARN. If you specify only the function name, it is limited to 64 characters in length.

Length Constraints: Minimum length of 1. Maximum length of 140.

Pattern: (arn:(aws[a-zA-Z-]*)?:lambda:)?([a-z]{2}(-gov)?-[a-z]+-\d{1}:)?(\d{12}:)?(function:)?([a-zA-Z0-9-_]+)(:(\$LATEST|[a-zA-Z0-9-_]+))?

Request Body

The request accepts the following data in JSON format.


The SHA256 hash of the deployment package you want to publish. This provides validation on the code you are publishing. If you provide this parameter, the value must match the SHA256 of the $LATEST version for the publication to succeed. You can use the DryRun parameter of UpdateFunctionCode to verify the hash value that will be returned before publishing your new version.

Type: String

Required: No


The description for the version you are publishing. If not provided, AWS Lambda copies the description from the $LATEST version.

Type: String

Length Constraints: Minimum length of 0. Maximum length of 256.

Required: No


An optional value you can use to ensure you are updating the latest update of the function version or alias. If the RevisionID you pass doesn't match the latest RevisionId of the function or alias, it will fail with an error message, advising you retrieve the latest function version or alias RevisionID using either GetFunction or GetAlias.

Type: String

Required: No

Response Syntax

HTTP/1.1 201 Content-type: application/json { "CodeSha256": "string", "CodeSize": number, "DeadLetterConfig": { "TargetArn": "string" }, "Description": "string", "Environment": { "Error": { "ErrorCode": "string", "Message": "string" }, "Variables": { "string" : "string" } }, "FunctionArn": "string", "FunctionName": "string", "Handler": "string", "KMSKeyArn": "string", "LastModified": "string", "Layers": [ { "Arn": "string", "CodeSize": number } ], "MasterArn": "string", "MemorySize": number, "RevisionId": "string", "Role": "string", "Runtime": "string", "Timeout": number, "TracingConfig": { "Mode": "string" }, "Version": "string", "VpcConfig": { "SecurityGroupIds": [ "string" ], "SubnetIds": [ "string" ], "VpcId": "string" } }

Response Elements

If the action is successful, the service sends back an HTTP 201 response.

The following data is returned in JSON format by the service.


The SHA256 hash of the function's deployment package.

Type: String


The size of the function's deployment package in bytes.

Type: Long


The function's dead letter queue.

Type: DeadLetterConfig object


The function's description.

Type: String

Length Constraints: Minimum length of 0. Maximum length of 256.


The function's environment variables.

Type: EnvironmentResponse object


The function's Amazon Resource Name.

Type: String

Pattern: arn:(aws[a-zA-Z-]*)?:lambda:[a-z]{2}(-gov)?-[a-z]+-\d{1}:\d{12}:function:[a-zA-Z0-9-_\.]+(:(\$LATEST|[a-zA-Z0-9-_]+))?


The name of the function.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 170.

Pattern: (arn:(aws[a-zA-Z-]*)?:lambda:)?([a-z]{2}(-gov)?-[a-z]+-\d{1}:)?(\d{12}:)?(function:)?([a-zA-Z0-9-_\.]+)(:(\$LATEST|[a-zA-Z0-9-_]+))?


The function Lambda calls to begin executing your function.

Type: String

Length Constraints: Maximum length of 128.

Pattern: [^\s]+


The KMS key used to encrypt the function's environment variables. Only returned if you've configured a customer managed CMK.

Type: String

Pattern: (arn:(aws[a-zA-Z-]*)?:[a-z0-9-.]+:.*)|()


The date and time that the function was last updated, in ISO-8601 format (YYYY-MM-DDThh:mm:ss.sTZD).

Type: String


A list of function layers.

Type: Array of Layer objects


The ARN of the master function.

Type: String

Pattern: arn:(aws[a-zA-Z-]*)?:lambda:[a-z]{2}(-gov)?-[a-z]+-\d{1}:\d{12}:function:[a-zA-Z0-9-_]+(:(\$LATEST|[a-zA-Z0-9-_]+))?


The memory allocated to the function

Type: Integer

Valid Range: Minimum value of 128. Maximum value of 3008.


Represents the latest updated revision of the function or alias.

Type: String


The function's execution role.

Type: String

Pattern: arn:(aws[a-zA-Z-]*)?:iam::\d{12}:role/?[a-zA-Z_0-9+=,.@\-_/]+


The runtime environment for the Lambda function.

Type: String

Valid Values: nodejs | nodejs4.3 | nodejs6.10 | nodejs8.10 | java8 | python2.7 | python3.6 | python3.7 | dotnetcore1.0 | dotnetcore2.0 | dotnetcore2.1 | nodejs4.3-edge | go1.x | ruby2.5 | provided


The amount of time that Lambda allows a function to run before terminating it.

Type: Integer

Valid Range: Minimum value of 1.


The function's AWS X-Ray tracing configuration.

Type: TracingConfigResponse object


The version of the Lambda function.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 1024.

Pattern: (\$LATEST|[0-9]+)


The function's networking configuration.

Type: VpcConfigResponse object



You have exceeded your maximum total code size per account. Limits

HTTP Status Code: 400


One of the parameters in the request is invalid. For example, if you provided an IAM role for AWS Lambda to assume in the CreateFunction or the UpdateFunctionConfiguration API, that AWS Lambda is unable to assume you will get this exception.

HTTP Status Code: 400


The RevisionId provided does not match the latest RevisionId for the Lambda function or alias. Call the GetFunction or the GetAlias API to retrieve the latest RevisionId for your resource.

HTTP Status Code: 412


The resource (for example, a Lambda function or access policy statement) specified in the request does not exist.

HTTP Status Code: 404


The AWS Lambda service encountered an internal error.

HTTP Status Code: 500


Request throughput limit exceeded

HTTP Status Code: 429

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: