How to debug aws lambda functions written in node js

Question

We have been developing AWS Lambda functions in Node JS for a few months. Can we debug, i.e. step through the Node JS code as we can with .Net C# code in Visual Studio?

Answer 1

If you are using serverless and serverless offline plugin to test in local. You can refer below:

If you are using windows, update the vscode launch.json and package.json as below :

// launch.json
{

    "version": "0.2.0",

   "configurations": [

       {

           "type": "node",

           "request": "launch",

           "name": "Debug Serverless",

           "cwd": "${workspaceFolder}",

           "runtimeExecutable": "npm",

           "runtimeArgs": [

               "run",

               "debug"

           ],

           "outFiles": [

               "${workspaceFolder}/handler.js"

           ],

           "port": 9229,

           "sourceMaps": true

       }

   ]

}

// package.json
....
"scripts": {
    "debug": "SET SLS_DEBUG=* && node --inspect %USERPROFILE%\\AppData\\Roaming\\npm\\node_modules\\serverless\\bin\\serverless offline -s dev"
  }

If on linux your debug script will be:

// package.json
....
"scripts": {
    "debug": "export SLS_DEBUG=* && node --inspect /usr/local/bin/serverless offline -s dev"
  }