[Dependency Cache] Dependency Cache on CI per Project [without GRADLE_RO_DEP_CACHE]

[ParaskP7]

Project Thread: paaHJt-7CE-p2
Related: #134 + buildkite-ci#570
(Softly) Depends On:

• WCAndroid#13288
• FluxC#3125
• ADC#39

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Description

This change:

1. Adds a project prefix (BUILDKITE_PIPELINE_SLUG) to the existing gradle dependency cache key to enable dependency cache per project. (3b051ba)
2. Enhances save_cache and restore_cache logging by:
   1. Echoing how long it takes to save/restore the cache. (f777f02)
   2. Echoing the (un)compressed cache size during save/restore. (938009b + fb579e8)
3. Replaces the read-only GRADLE_RO_DEP_CACHE dependency cache mechanism (using the $GRADLE_HOME/read-only-dependency-cache directory), with the more basic GRADLE_DEP_CACHE dependency cache mechanism (using $GRADLE_HOME/dependency-cache directory), for save/restore. (61b1d9d)
4. Adds a version suffix (V2) to the existing gradle dependency cache key to differentiate between the two, the previous GRADLE_RO_DEP_CACHE and the new GRADLE_DEP_CACHE dependency cache mechanisms. This was purely done for testing purposes, but I think it might be wise for us to keep this versioning system in place, just in case we update the mechanism again in the future and want to effectively test, then utilize that new change. PS: I am very open to feedback on that. (94d9f7a)

Note

Enhancing the save_cache and restore_cache scripts (2.) will positively affect all clients of these scripts, mainly improve things by logging some more information. But, do think if there is going to be a case when these changes might negatively effect some or all those other clients (`I couldn't).

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Testing Instructions

This GRADLE_DEP_CACHE version of a8c-ci-toolkit was thoroughly tested via the below test-only PRs, via the help of the android-staging agents (see buildkite-ci#570):

• WCAndroid
• JP/WPAndroid

To help you assessing that this change is safe use to use and will not cause any trouble for any project, try and follow the below:

• WCAndroid
  • Latest save related build:
    • Prior to all the tasks starting, verify that there NO restore cache triggered (no local pre-command hook has run).
    • When all the dependency download tasks finish, save cache get triggered:
      • Using the correct project prefix and version suffix.
      • Logging both, the time it took for the cache to be saved and the size of the saved cache.
  • Latest restore related build:
    • Prior to the assemble task starting, restore cache gets triggered:
      • Using the correct project prefix and version suffix.
      • Logging both, the time it took for the cache to be restored and the size of the restored cache.
      • Finally, that the restored cache is placed correctly.
    • As the assemble tasks starts, verify that there is NO mention of a read-only dependency cache cache.
• JP/WPAndroid
  • Latest save related build:
    • Prior to all the tasks starting, verify that there NO restore cache triggered (no local pre-command hook has run).
    • When all the dependency download tasks finish, save cache get triggered:
      • Using the correct project prefix and version suffix.
      • Logging both, the time it took for the cache to be saved and the size of the saved cache.
  • Latest restore related build:
    • Prior to the assemble task starting, restore cache gets triggered:
      • Using the correct project prefix and version suffix.
      • Logging both, the time it took for the cache to be restored and the size of the restored cache.
      • Finally, that the restored cache is placed correctly.
    • As the assemble tasks starts, verify that there is NO mention of a read-only dependency cache cache.

Note

The GRADLE_RO_DEP_CACHE version of a8c-ci-toolkit was also tested via the below test-only PRs:

• WCAndroid
• JP/WPAndroid

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Merge Instructions

• Wait for buildkite-ci#570 to be reviewed, approved, deployed and merged.
• Wait for WCAndroid#13288 to be reviewed, approved and merged. (restore cache hook removed)
• Wait for FluxC#3125 to be reviewed, approved and merged. (restore cache hook removed)
• Wait for ADC#39 to be reviewed, approved and merged. (save cache trigger removed)
• Remove do not merge label.
• Merge this PR.
• Close Add a prefix to Gradle cache scripts #98 and [Dependency Cache] Dependency Cache on CI per Project [with GRADLE_RO_DEP_CACHE] #134 test-only PRs.

Note

These WCAndroid#13288 + FluxC#3125 + ADC#39 PRs are not necessarily needed prior to merging this change, but it is better to clean things up and avoid any confusion with relation to having save/restore working on client/libraries projects, while it is actually not (and shouldn't be as of yet).

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• I have considered if this change warrants release notes and have added them to the appropriate section in the CHANGELOG.md if necessary.

[dangermattic]

	1 Warning
⚠️	Please add an entry in the CHANGELOG.md file to describe the changes made by this PR

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[wzieba]

Looks good to me 🎉

[iangmaia]

Looking good 👍