fix: clean results when taskrun retries

[cugykw]

Changes

Fixes #7125 .

Prior to this PR, after retrying taskrun, the task results of the last run will be retained, which may cause the running situation to be inconsistent with the results.

After this commit, the taskrun will clean up the last task results before retrying.

/kind bug

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Release Notes

The taskrun will clean up the last task results before retrying.

[tekton-robot]

Hi @cugykw. Thanks for your PR.

I'm waiting for a tektoncd member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/reconciler/taskrun/taskrun.go	85.4%	85.4%	0.0

[jerop]

/ok-to-test

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/reconciler/taskrun/taskrun.go	85.4%	85.4%	0.0

[jerop]

it makes sense to me to clean results before a retry attempt, would like to hear from other @tektoncd/core-maintainers though

please update the documentation with this change:

pipeline/docs/taskruns.md

Line 742 in e35a4db

- `status.StartTime` and `status.PodName` are unset to trigger another retry attempt.

also wondering if there's a way for us to checkpoint workspaces before a taskrun then reset to that state on retry attempts, but this can be figured out in future work -- maybe for now we just document that workspaces may be corrupted on retry so the task needs to handle that itself

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/reconciler/taskrun/taskrun.go	85.4%	85.4%	0.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/reconciler/taskrun/taskrun.go	85.4%	85.4%	0.0

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jerop

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[vdemeester]

also wondering if there's a way for us to checkpoint workspaces before a taskrun then reset to that state on retry attempts, but this can be figured out in future work -- maybe for now we just document that workspaces may be corrupted on retry so the task needs to handle that itself

That one is going to be a problem (at least in our current architecture) as we cannot really do anything here. Today, it kind-of falls down to the way the Task behave (and thus on the author of the task to make sure not to modify the workspace or in a indempotent way or something…)

[jerop]

also wondering if there's a way for us to checkpoint workspaces before a taskrun then reset to that state on retry attempts, but this can be figured out in future work -- maybe for now we just document that workspaces may be corrupted on retry so the task needs to handle that itself

That one is going to be a problem (at least in our current architecture) as we cannot really do anything here. Today, it kind-of falls down to the way the Task behave (and thus on the author of the task to make sure not to modify the workspace or in a indempotent way or something…)

Makes sense, we can just document that Tasks authors need to make sure that Workspaces are handled during retries

In the meantime, we can move forward with this fix for Results

[Yongxuanzhang]

/lgtm