1. What is the method to incorporate requirementstxt in a Pulumi Lambda build in TypeScript


    To incorporate a requirements.txt file in a Pulumi Lambda build using TypeScript, you would generally follow these steps:

    1. Define your requirements.txt file: This file should list all the Python dependencies your Lambda function requires.
    2. Use @pulumi/aws Lambda resource with inline code or asset/archive: Pulumi allows you to define Lambda functions either using inline source code or by pointing to code stored in S3 as an asset or archive.
    3. Package your Lambda code along with requirements.txt: Before deployment, use a tool to package your Python code and its dependencies into a zip file.
    4. Deploy your Lambda with Pulumi: Set the code property of the Lambda function to point to the packaged asset.

    Below is a sample Pulumi program that demonstrates these steps:

    import * as pulumi from '@pulumi/pulumi'; import * as aws from '@pulumi/aws'; import * as fs from 'fs'; import * as path from 'path'; import { PythonPackageArchive } from './PythonPackageArchive'; // Directory where the Lambda function's source code is located const lambdaSourceDir = './lambda'; // Generate a zip archive of the Lambda source code and dependencies. const lambdaArchive = new PythonPackageArchive('myLambdaPackage', { sourceDirectory: lambdaSourceDir, }); // Create a new Lambda function and provide the packaged zip archive as the code. const lambdaFunction = new aws.lambda.Function('myLambdaFunction', { runtime: aws.lambda.Python3d6Runtime, code: lambdaArchive.asset, handler: 'index.handler', // Assuming your handler is defined in index.py and called "handler". role: lambdaRole.arn, // IAM role with necessary permissions that the Lambda will assume }); // Exports the name and ARN of the Lambda function export const lambdaName = lambdaFunction.name; export const lambdaARN = lambdaFunction.arn;

    Next is the implementation of the PythonPackageArchive component, which packages the Python lambda code and requirements:

    import * as pulumi from '@pulumi/pulumi'; import * as path from 'path'; import * as child_process from 'child_process'; import * as pulumi_asset from '@pulumi/pulumi/asset'; export class PythonPackageArchive extends pulumi.ComponentResource { public readonly asset: pulumi.asset.AssetArchive; constructor(name: string, args: { sourceDirectory: string }, opts?: pulumi.ComponentResourceOptions) { super('my:components:PythonPackageArchive', name, {}, opts); const { sourceDirectory } = args; const requirementsPath = path.join(sourceDirectory, 'requirements.txt'); // Create an asset archive for the Lambda deployment package. this.asset = new pulumi.asset.AssetArchive({ '.': new pulumi.asset.FileArchive( // Running the packaging script and returning the path to the created zip file. PythonPackageArchive.runPackagingScript(sourceDirectory, requirementsPath) ), }); // Make sure to register the component outputs. this.registerOutputs({ asset: this.asset, }); } private static runPackagingScript(sourceDirectory: string, requirementsPath: string): string { // Check if the requirements.txt file exists and construct the output path. if (!fs.existsSync(requirementsPath)) { throw new Error(`requirements.txt not found at ${requirementsPath}`); } const outputPath = `/tmp/lambda_package-${path.basename(sourceDirectory)}.zip`; // Run the packaging script. This will install the dependencies and create a zip file. const result = child_process.spawnSync( 'bash', ['-c', ` set -e cd "${sourceDirectory}" pip install --target . -r requirements.txt zip -r "${outputPath}" . `], { stdio: 'inherit' } ); if (result.error || result.status !== 0) { throw new Error('Failed to package Lambda function'); } // Return the path to the packaged zip file. return outputPath; } }


    • The PythonPackageArchive class is a custom Pulumi ComponentResource designed to create a zip archive of Python source code, including all dependencies listed in requirements.txt.
    • The runPackagingScript method checks for the existence of requirements.txt, performs installation of the dependencies into the Python source directory, and creates a zip archive.
    • The aws.lambda.Function resource is instantiated with the archive from PythonPackageArchive as its deployment package, code.
    • The handler property of the Lambda is set to the name of the Python file and function within that file which serves as the entry point for the Lambda execution.

    Note: The Python dependency installation and packaging are performed by a child process that invokes pip and zip commands. This requires that you have Python and pip installed in your system where you run Pulumi. This example assumes the packaging process takes place on a UNIX-like system with common utilities like bash and zip. The actual Python function code (e.g., index.py and requirements.txt) needs to live in the specified sourceDirectory.

    Ensure you create a suitable IAM role and attach the necessary policies for the Lambda to execute correctly, which is referenced in lambdaRole.arn in the example.