Deploying a Lambda function using the AWS CDK in AWS CloudShell

This tutorial shows you how to deploy a Lambda function to your account using the AWS Cloud Development Kit (AWS CDK) in CloudShell.

Prerequisites

• Bootstrap your account for use with the AWS CDK. For information about bootstrapping with AWS CDK, see Bootstrapping in the AWS CDK v2 Developer Guide. If you haven't bootstrapped the account, you can run cdk bootstrap in CloudShell.

• Make sure you have the appropriate permissions to deploy resources to your account. Administrator permissions are recommended.

Tutorial procedure

The following tutorial outlines how to deploy a Docker container-based Lambda function using the AWS CDK in CloudShell.

1. Create a new folder in your home directory.

   mkdir ~/docker-cdk-tutorial

2. Navigate to the folder you created.

   cd ~/docker-cdk-tutorial

3. Install the AWS CDK dependencies locally.

   npm install aws-cdk aws-cdk-lib

   

4. Create a skeleton AWS CDK project in the folder that you created.

   touch cdk.json
   mkdir lib
   touch lib/docker-tutorial.js lib/Dockerfile lib/hello.js

5. Using a text editor, for example nano cdk.json, open the file and paste the following content into it.

   {
     "app": "node lib/docker-tutorial.js"
   }

6. Open the lib/docker-tutorial.js file and paste the following content into it.

   // this file defines the CDK constructs we want to deploy
   
   const { App, Stack } = require('aws-cdk-lib');
   const { DockerImageFunction, DockerImageCode } = require('aws-cdk-lib/aws-lambda');
   const path = require('path');
   
   // create an application
   const app = new App();
   
   // define stack
   class DockerTutorialStack extends Stack {
     constructor(scope, id, props) {
       super(scope, id, props);
   
       // define lambda that uses a Docker container
       const dockerfileDir = path.join(__dirname);
       new DockerImageFunction(this, 'DockerTutorialFunction', {
         code: DockerImageCode.fromImageAsset(dockerfileDir),
         functionName: 'DockerTutorialFunction',
       });
     }
   }
   
   // instantiate stack
   new DockerTutorialStack(app, 'DockerTutorialStack');

7. Open the lib/Dockerfile and paste the following content into it.

   # Use a NodeJS 20.x runtime
   FROM public.ecr.aws/lambda/nodejs:20
   
   # Copy the function code to the LAMBDA_TASK_ROOT directory
   # This environment variable is provided by the lambda base image
   COPY hello.js ${LAMBDA_TASK_ROOT}
   
   # Set the CMD to the function handler
   CMD [ "hello.handler" ]

8. Open the lib/hello.js file and paste the following content into it.

   // define the handler
   exports.handler = async (event) => {
     // simply return a friendly success response
     const response = {
       statusCode: 200,
       body: JSON.stringify('Hello, World!'),
     };
     return response;
   };

9. Use the AWS CDK CLI to synthesize the project and deploy the resources. You must bootstrap your account.

   npx cdk synth
   npx cdk deploy --require-approval never

   

10. Invoke the Lambda function to confirm and verify it.

    aws lambda invoke --function-name DockerTutorialFunction out.json
    jq . out.json

    

    You have now successfully deployed a Docker container-based Lambda function using the AWS CDK. For more information on AWS CDK, see the AWS CDKv2 Developer Guide. If you encounter errors or run into issues when trying to complete this tutorial, see the Troubleshooting section of this guide for help.

Clean up

You have now successfully deployed a Docker container-based Lambda function using the AWS CDK. Inside the AWS CDK project, run the following command to delete the associated resources. You will be prompted to confirm the deletion.

• npx cdk destroy DockerTutorialStack

• To remove the files and resources you created in this tutorial from your AWS CloudShell environment, run the following command.

  cd ~
  rm -rf ~/docker-cli-tutorial