TEP-0111 - Propagating workspaces in Taskrun

This POC illustrates propagating workspaces defined at the `pipelinerun` stage and directly referred at the `spec`. There is no need to specify it in the `pipelinespec` followed by `tasks` and `taskspec`.

docs/install.md

@@ -427,6 +427,7 @@ Features currently in "alpha" are:
 | [Isolated `Step` & `Sidecar` `Workspaces`](./workspaces.md#isolated-workspaces)                       | [TEP-0029](https://github.com/tektoncd/community/blob/main/teps/0029-step-workspaces.md)                             | [v0.24.0](https://github.com/tektoncd/pipeline/releases/tag/v0.24.0) |                             |
 | [Hermetic Execution Mode](./hermetic.md)                                                              | [TEP-0025](https://github.com/tektoncd/community/blob/main/teps/0025-hermekton.md)                                   | [v0.25.0](https://github.com/tektoncd/pipeline/releases/tag/v0.25.0) |                             |
 | [Propagated `Parameters`](./taskruns.md#propagated-parameters)                                        | [TEP-0107](https://github.com/tektoncd/community/blob/main/teps/0107-propagating-parameters.md)                      | [v0.36.0](https://github.com/tektoncd/pipeline/releases/tag/v0.36.0) |                             |
+| [Propagated `Workspaces`](./pipelineruns.md#propagated-workspaces)                                    | [TEP-0111](https://github.com/tektoncd/community/blob/main/teps/0111-propagating-workspaces.md)                      |                                                                      |                             |
 | [Windows Scripts](./tasks.md#windows-scripts)                                                         | [TEP-0057](https://github.com/tektoncd/community/blob/main/teps/0057-windows-support.md)                             | [v0.28.0](https://github.com/tektoncd/pipeline/releases/tag/v0.28.0) |                             |
 | [Remote Tasks](./taskruns.md#remote-tasks) and [Remote Pipelines](./pipelineruns.md#remote-pipelines) | [TEP-0060](https://github.com/tektoncd/community/blob/main/teps/0060-remote-resolutiond.md)                          |                                                                      |                             |
 | [Debug](./debug.md)                                                                                   | [TEP-0042](https://github.com/tektoncd/community/blob/main/teps/0042-taskrun-breakpoint-on-failure.md)               | [v0.26.0](https://github.com/tektoncd/pipeline/releases/tag/v0.26.0) |                             |

docs/taskruns.md

@@ -422,6 +422,86 @@ For more information, see the following topics:
 - For a list of supported `Volume` types, see [Specifying `VolumeSources` in `Workspaces`](workspaces.md#specifying-volumesources-in-workspaces).
 - For an end-to-end example, see [`Workspaces` in a `TaskRun`](../examples/v1beta1/taskruns/workspace.yaml).
 
+#### Propagated Workspaces
+
+**([alpha only](https://github.com/tektoncd/pipeline/blob/main/docs/install.md#alpha-features))**
+
+When using an embedded spec, workspaces from the parent `TaskRun` will be
+propagated to any inlined specs without needing to be explicitly defined. This
+allows authors to simplify specs by automatically propagating top-level
+workspaces down to other inlined resources.
+**Workspace substutions will only be made for `commands`, `args` and `script` fields of `steps`, `stepTemplates`, and `sidecars`.**
+
+```yaml
+apiVersion: tekton.dev/v1beta1 
+kind: TaskRun                  
+metadata:
+  generateName: propagating-workspaces-
+spec:
+  taskSpec:                    
+    steps:                     
+      - name: simple-step      
+        image: ubuntu          
+        command:               
+          - echo               
+        args:                  
+          - $(workspaces.tr-workspace.path)
+  workspaces:                  
+  - emptyDir: {}               
+    name: tr-workspace
+```
+
+Upon execution, the workspaces will be interpolated during resolution.
+
+```yaml
+apiVersion: tekton.dev/v1beta1
+kind: TaskRun
+metadata:
+  name: propagating-workspaces-ndxnc
+  ...
+spec:
+  serviceAccountName: default
+  taskSpec:
+    steps:
+    - args:
+      - $(workspaces.tr-workspace.path)
+      command:
+      - echo
+      image: ubuntu
+      name: simple-step
+      resources: {}
+  timeout: 1h0m0s
+  workspaces:
+  - emptyDir: {}
+    name: tr-workspace
+status:
+  completionTime: "2022-09-09T17:34:22Z"
+  conditions:
+  - lastTransitionTime: "2022-09-09T17:34:22Z"
+    message: All Steps have completed executing
+    reason: Succeeded
+    status: "True"
+    type: Succeeded
+  podName: propagating-workspaces-ndxnc-pod
+  startTime: "2022-09-09T17:34:17Z"
+  steps:
+  ...
+  taskSpec:
+    steps:
+    - args:
+      - /workspace/tr-workspace
+      command:
+      - echo
+      image: ubuntu
+      name: simple-step
+      resources: {}
+    workspaces:
+    - name: tr-workspace
+
+```
+
+Workspaces can be propagated to embedded task specs, not referenced Tasks. For more information, see [Referenced TaskRuns within Embedded PipelineRuns](pipelineruns.md#referenced-taskruns-within-embedded-pipelineruns).
+
 ### Specifying `Sidecars`
 
 A `Sidecar` is a container that runs alongside the containers specified

docs/tasks.md

@@ -726,6 +726,8 @@ spec:
 For more information, see [Using `Workspaces` in `Tasks`](workspaces.md#using-workspaces-in-tasks)
 and the [`Workspaces` in a `TaskRun`](../examples/v1beta1/taskruns/workspace.yaml) example YAML file.
 
+Workspaces can be propagated to embedded task specs, not referenced Tasks. For more information, see [Referenced TaskRuns within Embedded PipelineRuns](pipelineruns.md#referenced-taskruns-within-embedded-pipelineruns). 
+
 ### Emitting `Results`
 
 A Task is able to emit string results that can be viewed by users and passed to other Tasks in a Pipeline. These

examples/v1beta1/taskruns/alpha/propagating_workspaces.yaml

@@ -0,0 +1,16 @@
+apiVersion: tekton.dev/v1beta1
+kind: TaskRun
+metadata:
+  generateName: propagating-workspaces-
+spec:
+  taskSpec:
+    steps:
+      - name: simple-step
+        image: ubuntu
+        command:
+          - echo
+        args:
+          - $(workspaces.tr-workspace.path)
+  workspaces:
+  - emptyDir: {}
+    name: tr-workspace

pkg/apis/pipeline/v1/task_types.go

@@ -21,6 +21,7 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"knative.dev/pkg/kmeta"
 )
 
@@ -95,6 +96,60 @@ type TaskSpec struct {
 	Results []TaskResult `json:"results,omitempty"`
 }
 
+func findWorkspaceSubstitutionLocationsInSidecars(sidecars []Sidecar) sets.String {
+	locationsToCheck := sets.NewString()
+	for _, sidecar := range sidecars {
+		locationsToCheck.Insert(sidecar.Script)
+
+		for i := range sidecar.Args {
+			locationsToCheck.Insert(sidecar.Args[i])
+		}
+
+		for i := range sidecar.Command {
+			locationsToCheck.Insert(sidecar.Command[i])
+		}
+	}
+	return locationsToCheck
+}
+
+func findWorkspaceSubstitutionLocationsInSteps(steps []Step) sets.String {
+	locationsToCheck := sets.NewString()
+	for _, step := range steps {
+		locationsToCheck.Insert(step.Script)
+
+		for i := range step.Args {
+			locationsToCheck.Insert(step.Args[i])
+		}
+
+		for i := range step.Command {
+			locationsToCheck.Insert(step.Command[i])
+		}
+	}
+	return locationsToCheck
+}
+
+func findWorkspaceSubstitutionLocationsInStepTemplate(stepTemplate *StepTemplate) sets.String {
+	locationsToCheck := sets.NewString()
+
+	for i := range stepTemplate.Args {
+		locationsToCheck.Insert(stepTemplate.Args[i])
+	}
+
+	for i := range stepTemplate.Command {
+		locationsToCheck.Insert(stepTemplate.Command[i])
+	}
+	return locationsToCheck
+}
+
+// FindWorkspaceSubstitutionLocationsInTask returns a set of all the locations in the TaskSpec  where we can apply substitutions.
+func (ts *TaskSpec) FindWorkspaceSubstitutionLocationsInTask() sets.String {
+	locationsToCheck := sets.NewString()
+	locationsToCheck.Insert(findWorkspaceSubstitutionLocationsInSteps(ts.Steps).List()...)
+	locationsToCheck.Insert(findWorkspaceSubstitutionLocationsInSidecars(ts.Sidecars).List()...)
+	locationsToCheck.Insert(findWorkspaceSubstitutionLocationsInStepTemplate(ts.StepTemplate).List()...)
+	return locationsToCheck
+}
+
 // TaskList contains a list of Task
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
 type TaskList struct {

pkg/apis/pipeline/v1/task_types_test.go

@@ -0,0 +1,75 @@
+/*
+Copyright 2019 The Tekton Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package v1_test
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	v1 "github.com/tektoncd/pipeline/pkg/apis/pipeline/v1"
+	"github.com/tektoncd/pipeline/test/diff"
+	"k8s.io/apimachinery/pkg/util/sets"
+)
+
+func TestTaskSpec_FindWorkspaceSubstitutionLocationsInTask(t *testing.T) {
+	tests := []struct {
+		name string
+		ts   *v1.TaskSpec
+		want sets.String
+	}{{
+		name: "completespec",
+		ts: &v1.TaskSpec{
+			Steps: []v1.Step{{
+				Name:    "step-name",
+				Image:   "step-image",
+				Script:  "step-script",
+				Command: []string{"step-command"},
+				Args:    []string{"step-args"},
+			}},
+			Sidecars: []v1.Sidecar{{
+				Name:    "sidecar-name",
+				Image:   "sidecar-image",
+				Script:  "sidecar-script",
+				Command: []string{"sidecar-command"},
+				Args:    []string{"sidecar-args"},
+			}},
+			StepTemplate: &v1.StepTemplate{
+				Image:   "steptemplate-image",
+				Command: []string{"steptemplate-command"},
+				Args:    []string{"steptemplate-args"},
+			},
+		},
+		want: sets.NewString(
+			"step-script",
+			"step-args",
+			"step-command",
+			"sidecar-script",
+			"sidecar-args",
+			"sidecar-command",
+			"steptemplate-args",
+			"steptemplate-command",
+		),
+	}}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := tt.ts.FindWorkspaceSubstitutionLocationsInTask()
+			if d := cmp.Diff(tt.want, got); d != "" {
+				t.Error(diff.PrintWantGot(d))
+			}
+		})
+	}
+}

pkg/apis/pipeline/v1beta1/pipelinerun_validation.go

@@ -143,7 +143,6 @@ func (ps *PipelineRunSpec) validatePipelineRunParameters(ctx context.Context) (e
 			}
 		}
 	}
-
 	return errs
 }
 

pkg/apis/pipeline/v1beta1/task_types.go

@@ -21,6 +21,7 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"knative.dev/pkg/kmeta"
 )
 
@@ -78,6 +79,61 @@ func (*Task) GetGroupVersionKind() schema.GroupVersionKind {
 	return SchemeGroupVersion.WithKind(pipeline.TaskControllerName)
 }
 
+func findWorkspaceSubstitutionLocationsInSidecars(sidecars []Sidecar) sets.String {
+	locationsToCheck := sets.NewString()
+	for _, sidecar := range sidecars {
+		locationsToCheck.Insert(sidecar.Script)
+
+		for i := range sidecar.Args {
+			locationsToCheck.Insert(sidecar.Args[i])
+		}
+
+		for i := range sidecar.Command {
+			locationsToCheck.Insert(sidecar.Command[i])
+		}
+	}
+	return locationsToCheck
+}
+
+func findWorkspaceSubstitutionLocationsInSteps(steps []Step) sets.String {
+	locationsToCheck := sets.NewString()
+	for _, step := range steps {
+		locationsToCheck.Insert(step.Script)
+
+		for i := range step.Args {
+			locationsToCheck.Insert(step.Args[i])
+		}
+
+		for i := range step.Command {
+			locationsToCheck.Insert(step.Command[i])
+		}
+	}
+	return locationsToCheck
+}
+
+func findWorkspaceSubstitutionLocationsInStepTemplate(stepTemplate *StepTemplate) sets.String {
+	locationsToCheck := sets.NewString()
+
+	if stepTemplate != nil {
+		for i := range stepTemplate.Args {
+			locationsToCheck.Insert(stepTemplate.Args[i])
+		}
+		for i := range stepTemplate.Command {
+			locationsToCheck.Insert(stepTemplate.Command[i])
+		}
+	}
+	return locationsToCheck
+}
+
+// FindWorkspaceSubstitutionLocationsInTask returns a set of all the locations in the TaskSpec  where we can apply substitutions.
+func (ts *TaskSpec) FindWorkspaceSubstitutionLocationsInTask() sets.String {
+	locationsToCheck := sets.NewString()
+	locationsToCheck.Insert(findWorkspaceSubstitutionLocationsInSteps(ts.Steps).List()...)
+	locationsToCheck.Insert(findWorkspaceSubstitutionLocationsInSidecars(ts.Sidecars).List()...)
+	locationsToCheck.Insert(findWorkspaceSubstitutionLocationsInStepTemplate(ts.StepTemplate).List()...)
+	return locationsToCheck
+}
+
 // TaskSpec defines the desired state of Task.
 type TaskSpec struct {
 	// Resources is a list input and output resource to run the task