Ts-node: Cannot find module 'ts-node/register' in VS Code Debug

[Jancat]

The VS Code Node debugger launch.json:

{
  "version": "0.2.0",
  "configurations": [
    {
      "type": "node",
      "request": "launch",
      "name": "Launch Program",
      "runtimeArgs": ["-r", "ts-node/register"],
      "args": ["${workspaceFolder}/index.ts"]
    }
  ]
}

I had globally installed the typescript and ts-node

ts-node -v

ts-node v5.0.1
node v9.10.1
typescript v2.8.1

When I execute the debugger, it threw the error:

node -r ts-node/register /home/jancat/projects/Node/huaban-crawl/index.ts 
module.js:545
    throw err;
    ^
Error: Cannot find module 'ts-node/register'
    at Function.Module._resolveFilename (module.js:543:15)
    at Function.Module._load (module.js:470:25)
    at Module.require (module.js:593:17)
    at Function.Module._preloadModules (module.js:750:12)
    at preloadModules (bootstrap_node.js:532:38)
    at startup (bootstrap_node.js:191:9)
    at bootstrap_node.js:666:3

[blakeembrey]

You need to npm install ts-node locally, not globally. This may need a PR to documentation if that's unclear.

[samuela]

I have ts-node installed locally. Here's my package.json:

{
  "name": "api",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "scripts": {
    "start": "ts-node src/index.ts",
    "test": "tslint --project tsconfig.json"
  },
  "devDependencies": {
    "ts-node": "^7.0.1",
    "tslint": "^5.11.0",
    "typescript": "^3.1.3"
  },
  "dependencies": {
    "graphql-yoga": "^1.16.7",
    "prisma-client-lib": "^1.19.0"
  }
}

but I'm still seeing

/usr/local/bin/node -r ts-node/register --inspect-brk=40133 api/src/index.ts 
Debugger listening on ws://127.0.0.1:40133/ceca7723-bfa1-4461-b97a-a17c1a1ec2fc
For help, see: https://nodejs.org/en/docs/inspector
Debugger attached.
internal/modules/cjs/loader.js:583
    throw err;
    ^
Error: Cannot find module 'ts-node/register'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:581:15)
    at Function.Module._load (internal/modules/cjs/loader.js:507:25)
    at Module.require (internal/modules/cjs/loader.js:637:17)
    at Module._preloadModules (internal/modules/cjs/loader.js:805:12)
    at preloadModules (internal/bootstrap/node.js:588:7)
    at startup (internal/bootstrap/node.js:269:9)
    at bootstrapNodeJSCore (internal/bootstrap/node.js:752:3)
Waiting for the debugger to disconnect...
Error: Cannot find module 'ts-node/register'
loader.js:581
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:581:15)
    at Function.Module._load (internal/modules/cjs/loader.js:507:25)
    at Module.require (internal/modules/cjs/loader.js:637:17)
    at Module._preloadModules (internal/modules/cjs/loader.js:805:12)
    at preloadModules (internal/bootstrap/node.js:588:7)
    at startup (internal/bootstrap/node.js:269:9)
    at bootstrapNodeJSCore (internal/bootstrap/node.js:752:3)

[blakeembrey]

@samuela And npm start works? And the node_modules is in the directory you're working in and not some child directory like api? This is pure node.js resolution here, not related to ts-node since the file is released with the package on NPM.

[samuela]

@blakeembrey Ah, my node_modules is in api. That's probably what's going on here.

[mprinc]

It is also important if your launch.json is not in the same folder as your project (i.e. package.json and therefore node_modules) that you set properly cwd in launch.json, for example:

"cwd": "${workspaceFolder}/<path_to_project>"

as otherwise, VSC will not find ts-node or typescript packages

[Amitesh]

I have install ts-node globally instead of making package dependency. I tried to link local package to the global one and that was helpful to resolve the ts-node/register issue.

$ npm link ts-node
C:\dev\projects\my-project\node_modules\ts-node -> C:\Program Files\nodejs\node_modules\ts-node

Hope this help!