Add PipelineSpec validation.

This adds validation for the following cases:
- duplicate PipelineTask Names
- invalid passedConstraint Names

pkg/apis/pipeline/v1alpha1/pipeline_types.go

@@ -98,7 +98,6 @@ type SourceBinding struct {
 	Key string `json:"key"`
 	// The Resource this binding is referring to
 	ResourceRef PipelineResourceRef `json:"resourceRef"`
-	// TODO: validate the passedConstraints values match previous Task names
 	// PassedConstraints is the list of Task names that the resource has to pass through.
 	// +optional
 	PassedConstraints []string `json:"passedConstraints,omitempty"`

pkg/apis/pipeline/v1alpha1/pipeline_validation.go

@@ -17,6 +17,8 @@ limitations under the License.
 package v1alpha1
 
 import (
+	"fmt"
+
 	"github.com/knative/pkg/apis"
 	"k8s.io/apimachinery/pkg/api/equality"
 )
@@ -33,5 +35,24 @@ func (ps *PipelineSpec) Validate() *apis.FieldError {
 		return apis.ErrMissingField(apis.CurrentField)
 	}
 
+	// Names cannot be duplicated
+	taskNames := map[string]struct{}{}
+	for _, t := range ps.Tasks {
+		if _, ok := taskNames[t.Name]; ok {
+			return apis.ErrMultipleOneOf("spec.tasks.name")
+		}
+		taskNames[t.Name] = struct{}{}
+	}
+
+	// passedConstraints should match other tasks.
+	for _, t := range ps.Tasks {
+		for _, isb := range t.InputSourceBindings {
+			for _, pc := range isb.PassedConstraints {
+				if _, ok := taskNames[pc]; !ok {
+					return apis.ErrInvalidKeyName(pc, fmt.Sprintf("spec.tasks.inputSourceBindings.%s", pc))
+				}
+			}
+		}
+	}
 	return nil
 }

pkg/apis/pipeline/v1alpha1/pipeline_validation_test.go

@@ -0,0 +1,128 @@
+/*
+Copyright 2018 The Knative 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 v1alpha1
+
+import (
+	"testing"
+)
+
+func TestPipelineSpec_Validate_Error(t *testing.T) {
+	type fields struct {
+		Tasks      []PipelineTask
+		Generation int64
+	}
+	tests := []struct {
+		name   string
+		fields fields
+	}{
+		{
+			name: "duplicate tasks",
+			fields: fields{
+				Tasks: []PipelineTask{
+					{
+						Name: "foo",
+					},
+					{
+						Name: "foo",
+					},
+				},
+			},
+		},
+		{
+			name: "invalid constraint tasks",
+			fields: fields{
+				Tasks: []PipelineTask{
+					{
+						Name: "foo",
+						InputSourceBindings: []SourceBinding{
+							{
+								Name:              "binding",
+								PassedConstraints: []string{"bar"},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ps := &PipelineSpec{
+				Tasks:      tt.fields.Tasks,
+				Generation: tt.fields.Generation,
+			}
+			if err := ps.Validate(); err == nil {
+				t.Error("PipelineSpec.Validate() did not return error, wanted error")
+			}
+		})
+	}
+}
+
+func TestPipelineSpec_Validate_Valid(t *testing.T) {
+	type fields struct {
+		Tasks      []PipelineTask
+		Generation int64
+	}
+	tests := []struct {
+		name   string
+		fields fields
+	}{
+		{
+			name: "no duplicate tasks",
+			fields: fields{
+				Tasks: []PipelineTask{
+					{
+						Name: "foo",
+					},
+					{
+						Name: "baz",
+					},
+				},
+			},
+		},
+		{
+			name: "valid constraint tasks",
+			fields: fields{
+				Tasks: []PipelineTask{
+					{
+						Name: "foo",
+						InputSourceBindings: []SourceBinding{
+							{
+								Name:              "binding",
+								PassedConstraints: []string{"bar"},
+							},
+						},
+					},
+					{
+						Name: "bar",
+					},
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ps := &PipelineSpec{
+				Tasks:      tt.fields.Tasks,
+				Generation: tt.fields.Generation,
+			}
+			if err := ps.Validate(); err != nil {
+				t.Errorf("PipelineSpec.Validate() returned error: %v", err)
+			}
+		})
+	}
+}