Build console with make bundle

[chuckwagoncomputing]

flock waits for a lock on a file; once it's unlocked, it locks it and holds the lock until the command is completed. This is necessary because parallel Gradle builds interfere with each other.

Green custom: https://github.com/chuckwagoncomputing/fw-custom-example/actions/runs/8020089442

[rusefillc]

@chuckwagoncomputing do we expect this to be happy on Windows?

[rusefillc]

This is necessary because parallel Gradle builds interfere with each other.

shall we disable parallel gradle? can you elaborate on the problem statement what is interfering with what how and when?

[chuckwagoncomputing]

When you try to run a Gradle task when another one is already running, they fail in all sorts of ways. Making each Gradle worker do its work sequentially wouldn't solve the problem because you would still have multiple Gradle workers running at the same time. I have solved this by using flock to make sure only one is running at any time.

[rusefillc]

@chuckwagoncomputing please ELI5 for me. Who is invoking multiple gradle instances in parallel?

[chuckwagoncomputing]

If you pass the -j flag to GNU Make with a number, it will execute that many recipes in parallel. If multiple recipes call Gradle, it is likely that those recipes will be run in parallel. We call make -j$(nproc), where nproc returns the number of logical processors in your computer. For any modern computer, this is more than one. The end result is that we have multiple instances of Gradle running in parallel. However, I have solved this problem using flock.

[rusefillc]

So a variation of https://discuss.gradle.org/t/avoiding-gradle-locking-issues-with-concurrent-gradle-task-runs/30259

[rusefillc]

I am concerned about long term maintainability of this complex bespoke solution

At least it should be documented as a code comment right next to magic

Ideally we need a much more official way of doing same. Not sure of " --no-daemon" is relevant but hopefully gradle has something official remedy for that?

random https://discuss.gradle.org/t/using-gradle-build-cache-in-parallel-ci-cd-pipeline-runs/44614

[mck1117]

hopefully gradle has something official remedy for that?

The official guidance is "please for the love of god don't call gradle from make"

[rusefillc]

@chuckwagoncomputing FYI pick 2e6f218

[chuckwagoncomputing]

do we expect this to be happy on Windows?

I expect it to work with Cygwin or WSL, if that's what you mean.

The official guidance is "please for the love of god don't call gradle from make"

@mck1117 Do you have a source, or can you explain why not?