IntelliJ IDEA 14 and angular-fullstack debug set up hanging on concurrent:server

Question

I've seen this post: Server hangs on Running "concurrent:server" (concurrent) task but the solutions there don't appear to be the source of what I'm seeing. I'm wondering if it's a bug with IntelliJ but thought I'd ask before I submit to Jetbrains.

I'm using a brand-new, freshly-built Yeoman angular-fullstack and trying to debug into app.js or seed.js for example - something that runs immediately after the server starts up. As such, I either need to start a server with node --debug-brk so the server waits until I manually connect the debugger or start the server in a way that IDEA connects its debugger immediately.

This runs just fine from the command line running grunt serve. However, doing the same in IDEA as a debug config hangs on the concurrent:server task.

This is all 100% out of the box angular-fullstack, but I'll put the code here for reference anyway.

Here's the portion of the "serve" task that runs when no target is specified, as in the case I'm talking about here:

grunt.task.run([
  'clean:server',
  'env:all',
  'injector:sass',
  'concurrent:server',
  'injector',
  'wiredep',
  'autoprefixer',
  'express:dev',
  'wait',
  'open',
  'watch'
]);

Here's the concurrent portion of the Gruntfile where things are getting hung up:

 concurrent: {
      server: [
        'sass',
      ],
      test: [
        'sass',
      ],
      debug: {
        tasks: [
          'nodemon',
          'node-inspector'
        ],
        options: {
          logConcurrentOutput: true
        }
      },
      dist: [
        'sass',
        'imagemin',
        'svgmin'
      ]
    }

More detail below but the only way I have this working right now is to change the concurrent:server line in the task to sass to just use what's in the server section of the concurrent task anyway. That

So right now I have the following options that I've tried, along with the associated problems I'm encountering:

Approach #1: Start the server via an IDEA NodeJS debug config running grunt serve

• IDEA uses the --debug-brk parameter so the server waits for the debugger to attached
• The debugger from IDEA connects immediately, so server continues to start up quickly
• Server stops at the "concurrent:server" task. I've left it running for 6m+ with no changes.
• I've done the same via command line outside of the IDEA debug config with the same command line and the same behavior, the only difference being that I connect IDEA's debugger manually to that running Node instance.
• Seems like the concurrent stuff is messing up IDEA? I've tried pulling the concurrent stuff out of there (in this case a sass task) and that works fine but towards the bottom

Here's the console output for this approach:

/usr/local/bin/node --debug-brk=65524 --nolazy --debug /usr/local/bin/grunt serve
debugger listening on port 65524
Running "serve" task

Running "clean:server" (clean) task

Running "env:all" (env) task

Running "injector:sass" (injector) task
Missing option `template`, using `dest` as template instead
Injecting scss files (3 files)
>> Nothing changed

Running "concurrent:server" (concurrent) task

Approach #2: Using the same debug config from #1, do a "run" instead of a "debug"

• IDEA doesn't use --debug-brk in the command line, nor --nolazy, first line is this instead: /usr/local/bin/node /usr/local/bin/grunt serve
• Grunt runs as it does on the command line but doesn't hook up the debugger nor necessarily give me time to do so either.

Per above the only way I got this working fully was to change out the concurrent:server portion of the task explicitly. My concern is if I do want the concurrent capability, I really have no way to debug the early-loaded portions of the app without unrolling the entire concurrent task.

My other option is to create a new task specific to IntelliJ that unrolls it, but that's still a hack...

Is this an IntellliJ bug or is something else going on?

Answer 1

The problem is caused by the way Grunt spawns child tasks. By default, the spawned child process uses the same debug port as a parent process - as a result the forked process is suspended and the application 'stalls'. See How to fork a child process that listens on a different debug port than the parent, for example.

Please try adding

process.execArgv = [];

at the top of your Gruntfile.js