webchannel-wrapper build process not compatible with web worker

[PCreations]

Describe your environment

• Operating System version: OSX 10.12.1
• Firebase SDK version: 4.6.0
• Firebase Product: firestore 4.5.2

Describe the problem

When trying to use firestore inside a webworker, the window object is not set to the self variables, as it is for auth build process for example, thus making firestore to fail as if we were trying to use the browser sdk in a node environnement.

I think the problem lies in the Closure compiler code of the webchannel-wrapper :
webchannel-wrapper/tools/build.js

// actual code
closureBuilder.build({
  name: 'firebase.webchannel.wrapper',
  srcs: glob([resolve(__dirname, '../src/**/*.js')]),
  externs: [resolve(__dirname, '../externs/overrides.js')],
  out: 'dist/index.js',
  options: {
    closure: {
      output_wrapper:
        "(function() {%output%}).call(typeof window !== 'undefined' ? window : this)",
      language_out: 'ECMASCRIPT5',
      compilation_level: 'ADVANCED_OPTIMIZATIONS'
    }
  }
});

// I think this should be done like this :
closureBuilder.build({
  name: 'firebase.webchannel.wrapper',
  srcs: glob([resolve(__dirname, '../src/**/*.js')]),
  externs: [resolve(__dirname, '../externs/overrides.js')],
  out: 'dist/index.js',
  options: {
    closure: {
      output_wrapper:
        "(function() {%output%}).call(typeof global !== 'undefined' ? global : typeof self !== 'undefined' ? self : typeof window !== 'undefined' ? window : {})",
      language_out: 'ECMASCRIPT5',
      compilation_level: 'ADVANCED_OPTIMIZATIONS'
    }
  }
});

When modifying this file, and yarn linking the package manually, I get rid of the "nodejs" like error (k.setTimeout is not defined, etc.) but some others pop out from browser.window dependent method like Image that are not defined in a webworker environnement (this error commes from the goog.net.WebChannel package).
Any chance to add support for using firestore in webworker ?

[mikelehen]

We resolved the webchannel / Image issue separately. Can you try your workaround again and see if the webworker issue is resolved? If so, we can likely get your change implemented (if you're willing, a PR would be most appreciated :-))

[r0bn]

i had the same error message with web workers, i tested the proposed change from @PCreations and it seems to work in web workers.

[PCreations]

Seems good now ! Maybe we can close this issue when the master branch is released :)

[mikelehen]

Holler if anybody is still seeing issues!