fix: return itself when getOutboundNodes from memoization Hit steps/DAG. Fixes: #7873

[shuangkun]

Fixes #7873

Motivation

The first step "hello-steps" should have one child (The SgNode of "whatever")，but when “hello-steps” hit memoize，it has no child because of getOutboundNodes from the node return nil. Prevents the next sgNode from becoming the child of the previous sgNode’s outboundNodes.

apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: memoized-bug-
spec:
  entrypoint: main
  templates:
  - name: main
    steps:
    - - name: hello-steps
        template: memoized
    - - name: whatever
        template: hello

  - name: memoized
    outputs:
      parameters:
      - name: msg
        valueFrom:
          parameter: "{{steps.hello-step.outputs.result}}"
    steps:
    - - name: hello-step
        template: hello
    memoize:
      key: "memoized-bug-steps-0"
      cache:
        configMap:
          name: my-config

  - name: hello
    container:
      image: alpine:latest
      command: [sh, -c]
      args: ["echo Hello"]

Modifications

return itself when getOutboundNodes from memoization Hit steps/DAG.

Verification

Local test and unit tests.

[shuangkun]

Hi,Joibel @Joibel I know you are very familiar with memoize, can you help review this, when a node hits the cache, its node id can be returned when getOutboundNodes. Thank you so much！

[Joibel]

Happy to look at it. I am at Kubecon/Argocon this week, so not sure whether I will get a chance until next week.

Can you get the test suite to ✅?

[shuangkun]

Happy to look at it. I am at Kubecon/Argocon this week, so not sure whether I will get a chance until next week.

Can you get the test suite to ✅?

Thanks, enjoy your conference! My question is not urgent, you can take a look at my question later when you have time. The test suite is OK.

[Joibel]

Looks good, just a couple of things to improve test robustness

[Joibel]

I'd like to test that we hit this condition once and only once (just in case we end up without this node in the Nodes list.

[shuangkun]

Thanks! I add it.

[Joibel]

LGTM. @agilgur5 @isubasinghe @terrytangyuan could you do the magic please

[agilgur5]

Backported cleanly to release-3.5 as 4e7d471