Warn user when on cel-expression is used along side on-target branch and on-event

[PuneetPunamiya]

This patch warns users in both the user events namespaces and controller logs when using on-event and on-target-branch annotations along side on-cel-expression

Hence warning users would avoid further confusion

Fixes: #1974

Changes

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  (update the documentation accordingly)

[chmouel]

i am not sure i understand that function? what does it do, why does it need to append ? i can understand the value of the function of that function but you can re-implement it in a more simple way, isnt it ? or perhaps it's not very well named and that makes it confusing?

[chmouel]

This is what i was thinking:

// checkPipelineRunAnnotation checks if the Pipelinerun has
// `on-event`/`on-target-branch annotations` with `on-cel-expression`
// and if present then warns the user that `on-cel-expression` will take precedence.
func checkPipelineRunAnnotation(prun *tektonv1.PipelineRun, logger *zap.SugaredLogger, eventEmitter *events.EventEmitter, repo *apipac.Repository) {
	// Define the annotations to check in a slice for easy iteration
	checks := []struct {
		key   string
		value string
	}{
		{"on-event", prun.GetObjectMeta().GetAnnotations()[keys.OnEvent]},
		{"on-target-branch", prun.GetObjectMeta().GetAnnotations()[keys.OnTargetBranch]},
	}

	// Preallocate the annotations slice with the exact capacity needed
	annotations := make([]string, 0, len(checks))

	// Iterate through each check and append the key if the value is non-empty
	for _, check := range checks {
		if check.value != "" {
			annotations = append(annotations, check.key)
		}
	}

	if len(annotations) > 0 {
		ignoredAnnotations := strings.Join(annotations, ", ")
		msg := fmt.Sprintf(
			"Warning: The Pipelinerun '%s' has 'on-cel-expression' defined along with [%s] annotation(s). The `on-cel-expression` will take precedence and these annotations will be ignored",
			prun.Name,
			ignoredAnnotations,
		)
		logger.Warnf(msg)
		eventEmitter.EmitMessage(repo, zap.WarnLevel, "RespositoryTakesOnCelExpressionPrecedence", msg)
	}
}

and have that function called in the for _, prun := range pruns loop with:

	checkPipelineRunAnnotation(prun, logger, eventEmitter, repo)

[PuneetPunamiya]

Yeah, thanks for the review. It does the same thing as the one which you suggested, but yes the name of the function sounds a bit confusing and also the one which you suggested seems to be a bit more simpler. Will update the PR, thanks

and have that function called in the for _, prun := range pruns loop with:
Yeah, adding it in the for loop but inside this condition

if celExpr, ok := prun.GetObjectMeta().GetAnnotations()[keys.OnCelExpression]; ok 

as this will check if it has cel expression and then will check for annotations