Cannot assign params with task results to other task value

[r0bj]

Expected Behavior

I can assign params with task results to other task value:

      params:
      - name: arg
        value: "$(params.prefix):$(tasks.generate-suffix.results.suffix)"

Actual Behavior

Cannot assign params with task results to other task value. Error message is generated:

validation failed: invalid value: Invalid result reference expression: Must be of the form \"tasks.<taskName>.results.<resultName>\": spec.tasks.params.value

Steps to Reproduce the Problem

pipeline.yaml:

apiVersion: tekton.dev/v1beta1
kind: PipelineRun
metadata:
  generateName: test-
spec:
  params:
  - name: prefix
    value: prefix
  pipelineSpec:
    params:
    - name: prefix
    tasks:
    - name: generate-suffix
      taskSpec:
        results:
        - name: suffix
        steps:
        - name: generate-suffix
          image: alpine
          script: |
            echo "suffix" > $(results.suffix.path)
    - name: do-something
      runAfter:
      - generate-suffix
      taskSpec:
        params:
        - name: arg
        steps:
        - name: do-something
          image: alpine
          script: |
            echo "$(params.arg)"
      params:
      - name: arg
        value: "$(params.prefix):$(tasks.generate-suffix.results.suffix)"

Executing this pipelinerun generates error message:

{"level":"warn","logger":"tekton.pipeline-controller","caller":"pipelinerun/pipelinerun.go:193","msg":"Failed to update PipelineRun status{error 25 0  admission webhook \"validation.webhook.pipeline.tekton.dev\" denied the request: validation failed: invalid value: Invalid result reference expression: Must be of the form \"tasks.<taskName>.results.<resultName>\": spec.tasks.params.value}","commit":"82e2758","knative.dev/controller":"pipeline-controller"}
{"level":"error","logger":"tekton.pipeline-controller","caller":"controller/controller.go:376","msg":"Reconcile error","commit":"82e2758","knative.dev/controller":"pipeline-controller","error":"1 error occurred:\n\t* admission webhook \"validation.webhook.pipeline.tekton.dev\" denied the request: validation failed: invalid value: Invalid result reference expression: Must be of the form \"tasks.<taskName>.results.<resultName>\": spec.tasks.params.value\n\n","stacktrace":"github.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller.(*Impl).handleErr\n\tgithub.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller/controller.go:376\ngithub.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller.(*Impl).processNextWorkItem\n\tgithub.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller/controller.go:362\ngithub.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller.(*Impl).Run.func2\n\tgithub.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller/controller.go:310"}

Additional Info

• Kubernetes version:

  Output of kubectl version:

Client Version: version.Info{Major:"1", Minor:"17", GitVersion:"v1.17.4", GitCommit:"8d8aa39598534325ad77120c120a22b3a990b5ea", GitTreeState:"clean", BuildDate:"2020-03-12T23:41:24Z", GoVersion:"go1.14", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"15+", GitVersion:"v1.15.11-gke.1", GitCommit:"aa93664bafe74f3c051e021b27a64e28ac34ab40", GitTreeState:"clean", BuildDate:"2020-03-18T22:49:35Z", GoVersion:"go1.12.17b4", Compiler:"gc", Platform:"linux/amd64"}

• Tekton Pipeline version:

  Output of tkn version or kubectl get pods -n tekton-pipelines -l app=tekton-pipelines-controller -o=jsonpath='{.items[0].metadata.labels.version}'

Client version: 0.8.0
Pipeline version: v0.11.1

[vdemeester]

/kind bug

[ghost]

I think the problem is here: https://github.com/tektoncd/pipeline/blob/master/pkg/apis/pipeline/v1alpha1/pipeline_validation.go#L143-L150

In this block we extract all variable substitutions: $(params.prefix) and $(tasks.generate-suffix.results.suffix). Then LooksLikeContainsResultRefs checks if any of those substitutions looks like a result substitution. tasks.generate-suffix.results.suffix does. So we then check if NewResultRefs parses for every substitution we extracted, returning an error if it doesn't. Here params.prefix will fail to parse because it isn't of the format tasks.<tName>.results.<rName>. So I think all we need to do here is filter out the non-result refs before attempting to call NewResultRefs on them?

[othomann]

will take a look at this.

[othomann]

@sbwsg this can be closed since #2393 has been merged. Thanks.

[vdemeester]

/close

[tekton-robot]

@vdemeester: Closing this issue.

In response to this:

/close

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.