Restart only one workflow

[individual-it]

In woodpecker all workflows are restarted if the "restart" button is clicked woodpecker-ci/woodpecker#1886
For us this is annoying when a single workflow failed e.g. because of flaky tests.
We could write to some permanent storage e.g. S3 the commitID and the workflow that passed. Before starting that workflow we would check the storage if that flag exists and just skip the run with exit 0 if it does.
Of course that does not make sense for build workflows, but only for real test workflows

CC @ScharfViktor @micbar

[individual-it]

before exiting the workflow could give a link to the previously passed one

[saw-jan]

Since Woodpecker doesn't support restarting individual workflows separately, my idea for this was:

• When a CI build starts, upload the current pipeline number to s3 using commit hash as path key
• When a restart happens on the same commit, check the previous pipeline number in s3 and get the pipeline details with that.
• Based on the previous pipeline info, run or skip the workflows.

The limitation in Woodpecker:

• Workflows do not get skipped with exit 78

Because of this limitation, we will have to touch all the steps of all the workflows where we want this to be implemented, just to skip the steps if the workflow was passed previously.

[individual-it]

we have a similar skip for when the cache is found if $BIN_CACHE_FOUND; then exit 0; fi

[saw-jan]

we have a similar skip for when the cache is found if $BIN_CACHE_FOUND; then exit 0; fi

yeah, that's needed in every step of all workflows, and it doesn't look good.
But if we want, then maybe we can start first with API/e2e test workflows

[saw-jan]

POC: opencloud-eu/opencloud#2099

✔️ When the workflow passed previously (steps skipped):

• Previous pipeline: https://ci.opencloud.rocks/repos/3/pipeline/717/61
• Current restarted pipeline: https://ci.opencloud.rocks/repos/3/pipeline/718/61

❌ When the workflow failed previously (steps run):

• Previous pipeline: https://ci.opencloud.rocks/repos/3/pipeline/717/54
• Current restarted pipeline: https://ci.opencloud.rocks/repos/3/pipeline/718/54