add supported luci builders

[keyonghan]

Description

Existing Luci builder configurations are stored in cocoon project. This is not efficient because we need to re-deploy the flutter-dashboard after changing the builder configuration. Additionally, with different channels/branches, a single place becomes challenging to support various requests.

Moving build configuration files to engine repo by itself will make things easier. Repos/branches will maintain their own copy of builder config file. From cocoon side, it can directly obtain the build config file for different repos/branches without redeploying the app engine.

JSON file will be validated via luci presubmit test, to be defined in engine.py recipe.

Related Issues

Related issue: flutter/flutter#62429, flutter/flutter#53371

[godofredoc]

Can we update the description with more information why we are moving these file to the engine repo?

[godofredoc]

Can you also please add a README file describing the expected format of the json file and a test?

[keyonghan]

Can you also please add a README file describing the expected format of the json file and a test?

README.md added. As for test, please find comment: flutter/cocoon#875 (comment)

[keyonghan]

Can we update the description with more information why we are moving these file to the engine repo?

Updated.

[keyonghan]

@dnfield @liyuqian could you help with the following questions?

• what is the best dir location to save luci config builders as a json file?
• Is there already a test coverage to check validity of a json file in engine? I see there are quite some json files in engine repo, how are their validity tested?
• If we add some new file, anything else to run/add/check to have tests, like build_test, to pass? I added a dart file, but it hit license error.
• Is there any guidelines/doc for new contributors to follow w.r.t. engine repo?

Thank you!

[liyuqian]

@dnfield @liyuqian could you help with the following questions?

• what is the best dir location to save luci config builders as a json file?

Somewhere in ci subdirectory.

• Is there already a test coverage to check validity of a json file in engine? I see there are quite some json files in engine repo, how are their validity tested?

Not that I'm aware of. But it should be simple to add as a Cirrus or LUCI test by checking the json from a Dart script.

• If we add some new file, anything else to run/add/check to have tests, like build_test, to pass? I added a dart file, but it hit license error.

For license errors, we often just copy the diffs from the presubmit test to the corresponding local files to make it pass. Reproducing and checking license errors locally was difficult according to my last experience so I just let presubmit tests check if the change is good.

• Is there any guidelines/doc for new contributors to follow w.r.t. engine repo?

See "Engine repo" section in https://github.com/flutter/flutter/wiki

[keyonghan]

Thank you @liyuqian !

[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat.

Reviewers: Read the Tree Hygiene page and make sure this patch meets those guidelines before LGTMing.

[godofredoc]

Not for this PR but given this validation will be used across repos I'm wondering if it could be moved to the recipes to avoid duplication.

[keyonghan]

That's a good point! moving the validation to a module should help. Will take a look.