Debugging uncompiled Typescript code running on a Docker container

Using ts-node and VS Code’s built-in debugger

I will explain how to achieve this in a very minimum setting.

Setup package.json

• Include ts-node in devDependencies .

"devDependencies": {
  ...
  
  "ts-node": "8.1.0"
}

• Create a script running the application on ts-node with enabling Node.js inspector. Specify the opening port for debugging in here.

"scripts": {
  ...
  "debug": "node -r ts-node/register --inspect=0.0.0.0:9229 src/app.ts"
}

Setup tsconfig.json

• Set true to sourceMap in compilerOptions

"compilerOptions": {
  ...
  "sourceMap": true
}

Setup debug configuration file

• Create .vscode/launch.json . Setting the same port specified in the newly created script on package.json .

{
  "version": "0.2.0",
  "configurations": [
    {
      "type": "node",
      "request": "attach",
      "name": "Docker: Attach to Node",
      "port": 9229,
      "address": "localhost",
      "sourceMapPathOverrides": {
        "/app/*": "${workspaceRoot}/*"
      }
    }
  ]
}

Probably the most important setting here is sourceMapPathOverrides specifying the sourceMap path in the container. You will specify the path for WORKDIR on your Dockerfile.

"sourceMapPathOverrides": {
  "<WORKDIR>/*": "${workspaceRoot}/*"
}

That’s all for the setting.

Should be possible debugging your app on VSCode.

A working example is in here.