Add write to disk options for build command

[thesujai]

Summary

This exposes --write-to-disk flag in build that writes file to disk instead of webpack

References

Fixes #4826

Reviewer guidance

In https://github.com/learningequality/kolibri/blob/develop/package.json#L15 Should there be a prod argument?

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[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-.pex
Windows Installer (EXE)	kolibri-0.16.0a0.dev0+git.788.gd3e55f93-unsigned.exe
Debian Package	kolibri_0.16.0a0.dev0+git.788.gd3e55f93-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.16.0a0.dev0+git.788.gd3e55f93-0.4.0.dmg
Android Package (APK)	kolibri-0.16.0a0.dev0+git.788.gd3e55f93-0.1.0-debug.apk
TAR file	kolibri-0.16.0a0.dev0+git.788.gd3e55f93.tar.gz
WHL file	kolibri-0.16.0a0.dev0+git.788.gd3e55f93-py2.py3-none-any.whl

[rtibbles]

I think the diff can be a bit smaller, and no need to disable the cache in this case that I can see.

[rtibbles]

Is there a reason not to utilize the webpack cache here? It should help with build performance either way.

Also, the use of hot is limited to the devserver being active, which we are passing false for, so I think this if could do the warn, then we could update the runWebpackBuild to simply be:

runWebpackBuild(mode, bundleData, !options.writeToDisk && mode === modes.DEV, options);

and not have to invoke it separately in the if statement.

[thesujai]

yes, I thought cache will fill the dev's system

[thesujai]

So yes, if hot and cache are not being modified then i will run the webpack build with your suggestions. Thank You

[rtibbles]

The cache is better managed than the writing built files to disk, so I wouldn't worry too much!

[thesujai]

Done!! Thank You

[rtibbles]

Excellent, thank you!