pub build packages directory for a Polymer app is too big

[johnmccutchan]

Reproduction steps:

$ cd runtime/bin/vmservice/client
$ pub build --mode=release

Look in build/web/packages

Specifically,

824K ./packages/polymer/src/js/polymer

That directory has two copies of polymer.js (polymer.js and polymer.concat.js). It also has two map files.

1.6M ./packages/web_components

Same problem here, directory has two copies of platform.js (platform.js and platform.concat.js). It also has two map files (each are half a meg in size!).

I'm not sure why .map files are being included in release mode build output.

[kasperl]

Added Triaged label.

[johnmccutchan]

Short term question: Can I safely delete one of the copies of each?

[sigmundch]

That's a good point. We could remove the *.concat.js versions in release mode.

The main challenge is how. I can imagine 2 options:
  - self-transformers: we could add a transformer to web_components and polymer to respectively remove part of their own code. This might slow down the build of polymer apps enough that we might want to do this differently. In particular, until pub-serve can use some sort of import-hooks, it does a lot of work just to load an extra transfomer.
  - global transformers: we are already planning to move polymer, smoke, and maybe observe to become part of a global-polymer transformer (see issue #9), so it might make sense to put this there too.

As for your question in #­2, yes. You can safely delete the *.concat.js files and the .map files after you build in release mode.

[johnmccutchan]

Thanks Siggi!

Removing the *.concat.js files reduced the compiled Observatory size by 0.5MB (or 25%). We were already removing the *.map files.

[sigmundch]

Added this to the 1.6 milestone.
Removed Pkg-Polymer label.
Added Pkg-PolymerBuild, Area-Pkg labels.

[sigmundch]

Removed this from the 1.6 milestone.
Added Polymer-P-1 label.

[sigmundch]

Removed Polymer-P-1 label.
Added Polymer-Milestone-Next label.

[sigmundch]

Added PolymerMilestone-Next label.

[sigmundch]

Removed Polymer-Milestone-Next label.

[kasperl]

Added this to the 1.6 milestone.

[sigmundch]

Removed this from the 1.6 milestone.

[sigmundch]

Marked this as being blocked by #18489.

[kasperl]

Added this to the 1.6 milestone.

[sigmundch]

Removed this from the 1.6 milestone.

[jakemac53]

I am going to see how I can clean this up without the global transformer, if nothing else by making the packages that we own perform some cleanup on themselves.