Support `nodemon` development setup by adding support to automatically re-attach when node is restarted

[joaomoreno]

Issue: #2103
Assignees:

• Windows @joaomoreno
• OS X @isidorn
• Linux @aeschli

Setting the new launch config attribute restart to true makes node-debug to automatically restart the session if the debug target has terminated. This is useful if you use nodemon to restart node on file changes.

Setup:

• on the command line start your node (server) program like this:

nodemon --debug server.js

• in VS Code create this attach launch config:

{
    "name": "Attach",
    "type": "node",
    "request": "attach",
    "port": 5858,
    "restart": true
}

• Now 'Attach' in VS Code.

Test:

• Verify that VS Code always restarts the debug session successfully after nodemon has restarted node.
• Test the behaviour if the session is stopped in VS Code or nodemon is killed.

[ronjouch]

In case it helps someone, chiming in that this support for nodemon works too with the (currently experimental) node2 debug type (V8 Inspector Protocol). Just change type to node2 and port to 9229, and run nodemon with --inspect instead of --debug EDIT as mentioned below, new correct way is just "type": "node", "protocol": "inspector" :) , attaching works and reloading on change works.

[ianfiske]

Just a small update @ronjouch for using the inspector protocol. Using node 6.10.2 and nodemon 1.11.0 with vscode 1.12.1, set type to node and protocol to inspector

"type": "node",
"runtimeArgs": [
   "--inspect"
],
"protocol": "inspector",
"port": 9229

[weinand]

@ianfiske the "runtimeArgs": [ "--inspect" ] and "port": 9229 is not needed because "protocol": "inspector" does exactly that (and more).
I even recommend against this redundancy because you can easily create an inconsistency if you keep "runtimeArgs": [ "--inspect" ] and change "protocol" to "legacy"...

[ianfiske]

Ah, thank you @weinand. If I remove only the runtimeArgs it fails (hence my mistake earlier that it was needed). But if I remove both runtimeArgs and port like you suggested, then it works!

[weinand]

Yes, if you set a port, we take this as an indication that you want to control everything yourself. In this case you have to specify the --inspect or --debug flag.

If no port is given, we pick a random free port and pass it to the runtime either as --debug=12345 or --inspect=12345 (depending on the value of protocol).

[cvharris]

This doesn't seem to be working still. Here's my launch.json:

{
  "type": "node",
  "request": "attach",
  "name": "Attach (Inspector Protocol)",
  "port": 9229,
  "protocol": "inspector"
}

When I run nodemon --inspect index.js the debugger attaches but on restart of the server it detaches and I have to start the VSCode debugger all over again.