求助：将Python+AWS CLI的Lambda下载脚本转为Node.js实现

Got it, let's turn that bash-based approach into a Node.js solution. We'll use the AWS SDK for JavaScript v3 (the latest, modular version) along with built-in Node.js modules for file handling, plus node-fetch to download the Lambda code packages.

Prerequisites #

• Node.js 16+ installed
• AWS credentials configured (via ~/.aws/credentials, environment variables, or IAM roles if running on AWS)
• Install required dependencies:

  npm install @aws-sdk/client-lambda node-fetch
  

Complete Node.js Script #

Create a file named download-lambdas.js with this code:

const { LambdaClient, ListFunctionsCommand, GetFunctionCommand } = require("@aws-sdk/client-lambda");
const fetch = require('node-fetch');
const fs = require('fs').promises;
const path = require('path');

// Initialize Lambda client (uses default AWS credentials chain)
const lambdaClient = new LambdaClient({ region: 'your-aws-region' }); // Replace with your region, e.g., 'us-east-1'

async function downloadLambdaFunctions() {
  // Create output directory if it doesn't exist
  const outputDir = path.join(__dirname, 'lambda_functions');
  await fs.mkdir(outputDir, { recursive: true });

  try {
    // Get list of all Lambda functions
    const listCommand = new ListFunctionsCommand({});
    const listResponse = await lambdaClient.send(listCommand);
    const functions = listResponse.Functions || [];

    if (functions.length === 0) {
      console.log('No Lambda functions found in this region.');
      return;
    }

    console.log(`Found ${functions.length} Lambda functions. Starting download...`);

    // Download each function concurrently (adjust concurrency if needed to avoid rate limits)
    await Promise.all(functions.map(async (lambdaFunc) => {
      const functionName = lambdaFunc.FunctionName;
      try {
        // Get the pre-signed URL for the Lambda code
        const getCommand = new GetFunctionCommand({ FunctionName: functionName });
        const getResponse = await lambdaClient.send(getCommand);
        const codeUrl = getResponse.Code.Location;

        // Download the code zip file
        const response = await fetch(codeUrl);
        if (!response.ok) {
          throw new Error(`Failed to download ${functionName}: HTTP ${response.status}`);
        }

        // Save the zip to the output directory
        const outputPath = path.join(outputDir, `${functionName}.zip`);
        const fileStream = fs.createWriteStream(outputPath);
        await new Promise((resolve, reject) => {
          response.body.pipe(fileStream);
          response.body.on('error', reject);
          fileStream.on('finish', resolve);
        });

        console.log(`Successfully downloaded: ${functionName}`);
      } catch (err) {
        console.error(`Failed to download ${functionName}:`, err.message);
      }
    }));

    console.log('\nCompleted downloading all Lambda functions!');
  } catch (err) {
    console.error('Error fetching Lambda function list:', err.message);
  }
}

// Run the download function
downloadLambdaFunctions();

Key Details & Customizations #

• Region: Replace 'your-aws-region' with your actual AWS region (e.g., 'us-west-2').
• Concurrency: The script uses Promise.all to download functions concurrently. If you hit AWS rate limits, you can modify this to process functions in batches or add a small delay between requests.
• Credentials: The Lambda client uses the default AWS credential chain, so it will pick up credentials from environment variables (AWS_ACCESS_KEY_ID/AWS_SECRET_ACCESS_KEY), ~/.aws/credentials, or IAM roles if running on an AWS resource like EC2/EKS.
• Error Handling: The script includes basic error handling to log failures for individual functions without stopping the entire download process.

How to Run #

1. Save the script as download-lambdas.js
2. Install dependencies (as listed in prerequisites)
3. Replace the region with your own
4. Run the script:

   node download-lambdas.js
   

Your Lambda function zip files will be saved in a lambda_functions directory in the same folder as the script.

内容的提问来源于stack exchange，提问作者Dlindau