[feat] Skip stages when the commit is not important (Analysis,WaitApproval,Wait,ScriptRun)

[t-kikuc]

What would you like to be added

• A new feature of skipping the ANALYSIS or WAIT_APPROVAL stages when the commit diff is not important.

• The configurable conditions of skipping the stage:

  • changed file path patterns (cf. GitHub Actions > paths)
  • commit message (prefix)

Why is it needed

• Some users would like to skip the ANALYSIS or WAIT_APPROVAL stages for faster and automatic deployment when the commit diff does not deserve analysis or approval.

• use cases:
  (a) When you modify only the HorizontalPodAutoscaler of K8s resources in your config repo, skip the WAIT_APPROVAL stage.
  (b) When you modify only go.mod dependencies in your source repo(not pipecd's config repo), skip the ANALYSIS stage.
  (c) Skip the WAIT_APPROVAL stage when the change in your source repo is small, but skip both the WAIT_APPROVAL and ANALYSIS stages when the change is tiny.

How to realize it

• Add the skip configuration to app.pipecd.yaml.

spec:
  pipeline:
    stages:
      # When changes are only `autoscaler.yaml` in any directory, skip this WAIT_APPROVAL.
      - name: WAIT_APPROVAL
        skip:
           paths:
              - "**/autoscaler.yaml"
      # When the commit message starts with "[skip analysis]", skip this ANALYSIS.
      - name: ANALYSIS
        skip:
            commitMessagePrefixes:
             - "[skip analysis]"

Example1. How to realize the use case (b)

1. Configure eventWatcher and pipeline in your app.pipecd.yaml.

spec:
  eventWatcher:
    - matcher:
        name: skip-analysis
      handler:
        type: GIT_UPDATE
        config:
          commitMessage: "[skip analysis] update xxx"
  pipeline:
      stages:
      - name: ANALYSIS
        skip:
            commitMessagePrefixes:
             - "[skip analysis]"

2. Let your CI publish an event named skip-analysis if only go.mod is changed.

Example2. How to realize the use case (c)

1. Configure eventWatcher and pipeline in your app.pipecd.yaml.

spec:
  eventWatcher:
    - matcher:
        name: small-change
      handler:
        type: GIT_UPDATE
        config:
          commitMessage: "[small change] update xxx"
    - matcher:
        name: tiny-change
      handler:
        type: GIT_UPDATE
        config:
          commitMessage: "[tiny change] update yyy"
  pipeline:
      stages:
      - name: WAIT_APPROVAL
        skip:
           commitMessagePrefixes:
              - "[small change]"
              - "[tiny change]"
      - name: ANALYSIS
        skip:
            commitMessagePrefixes:
             - "[tiny change]"

2. Let your CI publish an event named small-change to skip only WAIT_APPROVAL, and tiny-change to skip both WAIT_APPROVAL and ANALYSIS.

Possible Extensions

• In addition to commitMessagePrefixes, it would be better to have other options like:
  • skip.commitMessageOrBodyContains: []string
    • It skips the stage when the title or body of the commit contains words you specify.
  • skip.commitMessageOrBodyContainsCommand: bool
    • It skips the stage when the title or body of the commit contains specific commands like [skip analysis], [skip stage], etc.
    • cf. GitHub Actions > Skipping workflow runs

[t-kikuc]

[Acknowledgment]
I made this feature idea with @peaceiris, thanks!

[khanhtc1202]

I would like to add WAIT stage to the supported list, since it similar with the above 2 stages.

[t-kikuc]

I would like to add WAIT stage to the supported list, since it similar with the above 2 stages.

thanks, I agree with you and it's easily possible.

[t-kikuc]

cf. Skipping the ANALYSIS stage manually on the console is already available by:

• Add a dialog for skipping the analysis stage #3528
• Handle skipped stage by piped #3525

[peaceiris]

The SCRIPT_RUN stage is also useful if supported.

In our case, we plan to trigger an e2e testing by a script run stage. The stage should be skipped for quick rollback.

[t-kikuc]

I'll take this PR