tor-browser-build/projects/common/how-to-update-glean-parser.txt

In order to be able to do offline builds for mobile we need to collect and
distribute Glean dependencies beforehand.[1]

There are three steps involved in the process:
  1) Finding out the `glean_parser` version
  2) Downloading and verifying the dependencies
  3) Bundling the dependencies up and pushing them to the sources mirror

1)

The `glean_parser` version is available in glean-core/python/setup.py in the
Glean code repositoroy.[2] So, make sure which Glean version your
`android-components` tag is using (`mozilla_glean` in
buildSrc/src/main/java/Dependencies.kt has it) and then track `glean_parser`
down in the respective Glean tag.

2)

Create a directory `glean-wheels` and change into it. Then download packages for
`glean_parser` and its dependencies using

`python3 -m pip download glean_parser==$glean_parser`

($glean_parser being the version from step 1 above and Python 3 needs to be 3.6;
ideally, we take the artifact we built and will use during the build later on as
well.)

There is no really good way (yet) to verify that `pip` gave us actually what we
wanted. We can download `glean_parser` and its dependencies using a different
network path, though, e.g. by using `torsocks`. Comparing the results of both
downloads should yield the exact same binaries.

3)

Update the `glean_parser` version in `rbm.conf, tar `glean-wheels` up and
compress it:

`tar cfj glean-wheels-$glean_parser.tar.bz2 glean-wheels`

Upload the compressed tarball to the sources mirror and update the SHA-256 sum of
it in the respective projects.

[1] See: https://bugzilla.mozilla.org/show_bug.cgi?id=1651662 for details.
[2] https://github.com/mozilla/glean