fix: gracefully handle invalid CronWorkflows and simplify logic. Fixes #14047

[MasonM]

Fixes #14047 and fixes #14009

Motivation

If you have a CronWorkflow that's missing both schedules and schedule, or has schedules set to an empty array, you'll get an error in the UI when visiting /cron-workflows. This appears to have been introduced in #12616. You could argue this isn't a bug, since such CronWorkflows aren't valid, but multiple users have reported this, so we should gracefully handle it.

Modifications

This updates the UI code that fetches CronWorkflows from the API to normalize the response with a new normalizeSchedules() function that sets schedules to an empty array if it isn't present and automatically converts schedule to schedules:

argo-workflows/ui/src/shared/services/cron-workflow-service.ts

Lines 5 to 17 in 8461afb

	// Handle CronWorkflows using the deprecated "schedule" field by automatically
	// migrating them to use "schedules".
	// Also, gracefully handle invalid CronWorkflows that are missing both
	// "schedule" and "schedules".
	function normalizeSchedules(cronWorkflow: any): CronWorkflow {
	cronWorkflow.spec.schedules ??= [];
	// TODO: Delete this once we drop support for "schedule"
	if ((cronWorkflow.spec.schedule ?? '') != '') {
	cronWorkflow.spec.schedules.push(cronWorkflow.spec.schedule);
	delete cronWorkflow.spec.schedule;
	}
	return cronWorkflow as CronWorkflow;
	}

Then, I deleted all the logic for handling schedule, since everything can now safely assume that schedules is present and is a non-empty array. Once we drop support for schedule completely, we could delete the logic for converting that to schedules, but it's only a few lines of code. I also added some basic tests.

Verification

First, I used kubectl apply to manually create three CronWorkflows, one missing both schedule and schedules, one with schedules set to an empty array, and one with schedule:

apiVersion: argoproj.io/v1alpha1
kind: CronWorkflow
metadata:
  name: testschedulesmissinhg
spec:
  workflowSpec:
    entrypoint: main
    templates:
      - name: main
        container:
          image: argoproj/argosay:v2
---
apiVersion: argoproj.io/v1alpha1
kind: CronWorkflow
metadata:
  name: testschedulesemptyarray
spec:
  schedules: []
  workflowSpec:
    entrypoint: main
    templates:
      - name: main
        container:
          image: argoproj/argosay:v2
---
apiVersion: argoproj.io/v1alpha1
kind: CronWorkflow
metadata:
  name: testdeprecatedschedule
spec:
  schedule: "0 0 * * *"
  workflowSpec:
    entrypoint: main
    templates:
      - name: main
        container:
          image: argoproj/argosay:v2

I verified all three show up at http://localhost:8080/cron-workflows and can be edited:

I also verified that "Create New CronWorkflowworks with the exampleCronWorkflow`:

Documentation

N/A

[terrytangyuan]

Thank you for this and detailed verifications!

[Joibel]

/cherry-pick release-3.6

[gcp-cherry-pick-bot]

Cherry-pick failed with Merge error e9e7c4398c00621f697acf0002b7992028958daa into temp-cherry-pick-ee5b9b-release-3.6

[Joibel]

@MasonM, any chance you could backport this to 3.6 as requested in #14259?

[MasonM]

@Joibel Sure: #14419