Add build size bot workflow

[jcs98]

Motivation

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Test Plan

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Related PRs

(If this PR adds or changes functionality, please take some time to update the docs at https://github.com/facebook/docusaurus, and link to your PR here.)

[github-actions]

Size Change: -2 B (0%)

Total Size: 156 kB

ℹ️ View Unchanged

Filename	Size	Change
website/build/blog/2017/12/14/introducing-docusaurus/index.html	20.7 kB	-2 B (0%)
website/build/docs/introduction/index.html	180 B	0 B
website/build/index.html	5.83 kB	0 B
website/build/main.********.js	111 kB	0 B
website/build/styles.********.css	18.3 kB	0 B

_{compressed-size-action}

[slorber]

Hi

This looks like a good start but you should figure out options to make this way less verbose.

The js chunk hash is constantly changing (due to Webpack 4, webpack5 will be more deterministic afaik).
There's a option to "ignore" that hash: https://github.com/preactjs/compressed-size-action#dealing-with-hashed-filenames

Also, it's not useful to compare all HTML files with their previous versions, only a representative sample is enough (homepage, one doc, one blog post...)

What probably matters most are some specific js bundles, the heavy ones (like website/build/main.cd895b3b.js)

[jcs98]

Thank you for the tips @slorber
Working on them now

[jcs98]

Hi

This looks like a good start but you should figure out options to make this way less verbose.

The js chunk hash is constantly changing (due to Webpack 4, webpack5 will be more deterministic afaik).
There's a option to "ignore" that hash: https://github.com/preactjs/compressed-size-action#dealing-with-hashed-filenames

Also, it's not useful to compare all HTML files with their previous versions, only a representative sample is enough (homepage, one doc, one blog post...)

What probably matters most are some specific js bundles, the heavy ones (like website/build/main.cd895b3b.js)

Hi @slorber
I figured out the regex to avoid the hash changes

I've also picked 5 representative files for tracking the build size:

1. website/build/main.____.js
2. website/build/styles.____.css
3. website/build/index.html
4. website/build/docs/introduction/index.html
5. website/build/blog/2017/12/14/introducing-docusaurus/index.html

Please see the #1 (comment) above
Does this work as a part of the solution for facebook#3521 ?

[slorber]

thanks @jcs98 that looks nice. enough to be merged

can you open this pr to the main repo please?

[jcs98]

Thank you @slorber!
I was unable to point this PR to facebook:master so I opened a new PR here: facebook#3744