Changes to add results to a task

cmd/entrypoint/main.go

@@ -29,12 +29,12 @@ import (
 )
 
 var (
-	ep              = flag.String("entrypoint", "", "Original specified entrypoint to execute")
-	waitFiles       = flag.String("wait_file", "", "Comma-separated list of paths to wait for")
-	waitFileContent = flag.Bool("wait_file_content", false, "If specified, expect wait_file to have content")
-	postFile        = flag.String("post_file", "", "If specified, file to write upon completion")
-	terminationPath = flag.String("termination_path", "/tekton/termination", "If specified, file to write upon termination")
-
+	ep                  = flag.String("entrypoint", "", "Original specified entrypoint to execute")
+	waitFiles           = flag.String("wait_file", "", "Comma-separated list of paths to wait for")
+	waitFileContent     = flag.Bool("wait_file_content", false, "If specified, expect wait_file to have content")
+	postFile            = flag.String("post_file", "", "If specified, file to write upon completion")
+	terminationPath     = flag.String("termination_path", "/tekton/termination", "If specified, file to write upon termination")
+	results             = flag.String("results", "", "If specified, list of file names that might contain task results")
 	waitPollingInterval = time.Second
 )
 
@@ -51,6 +51,7 @@ func main() {
 		Waiter:          &realWaiter{},
 		Runner:          &realRunner{},
 		PostWriter:      &realPostWriter{},
+		Results:         strings.Split(*results, ","),
 	}
 	if err := e.Go(); err != nil {
 		switch t := err.(type) {

docs/developers/README.md

@@ -185,7 +185,7 @@ There are known issues with the existing implementation of sidecars:
 
 - When the `nop` image does provide the sidecar's command, the sidecar will continue to
 run even after `nop` has been swapped into the sidecar container's image
-field. See https://github.com/tektoncd/pipeline/issues/1347 for the issue
+field. See <https://github.com/tektoncd/pipeline/issues/1347> for the issue
 tracking this bug. Until this issue is resolved the best way to avoid it is to
 avoid overriding the `nop` image when deploying the tekton controller, or
 ensuring that the overridden `nop` image contains as few commands as possible.

pkg/apis/pipeline/v1alpha1/resource_types.go

@@ -123,6 +123,7 @@ type PipelineResourceResult struct {
 	Key         string              `json:"key"`
 	Value       string              `json:"value"`
 	ResourceRef PipelineResourceRef `json:"resourceRef,omitempty"`
+	ResultType  string              `json:"type,omitempty"`
 }
 
 // ResourceFromType returns an instance of the correct PipelineResource object type which can be

pkg/apis/pipeline/v1alpha1/task_types.go

@@ -64,6 +64,18 @@ type TaskSpec struct {
 
 	// Workspaces are the volumes that this Task requires.
 	Workspaces []WorkspaceDeclaration `json:"workspaces,omitempty"`
+
+	// Results are all possible results of this Task
+	Results []TaskResult `json:"results,omitempty"`
+}
+
+// TaskResult used to describe the results of a task
+type TaskResult struct {
+	// Name the given name
+	Name string `json:"name"`
+
+	// Description the given description
+	Description string `json:"description"`
 }
 
 // Step embeds the Container type, which allows it to include fields not

pkg/entrypoint/entrypointer.go

@@ -18,13 +18,19 @@ package entrypoint
 
 import (
 	"fmt"
+	"io/ioutil"
 	"time"
 
 	"github.com/tektoncd/pipeline/pkg/apis/pipeline/v1alpha1"
 	"github.com/tektoncd/pipeline/pkg/logging"
 	"github.com/tektoncd/pipeline/pkg/termination"
 )
 
+const (
+	// DefaultResultPath is the path for task result
+	DefaultResultPath = "/tekton/results/"
+)
+
 // Entrypointer holds fields for running commands with redirected
 // entrypoints.
 type Entrypointer struct {
@@ -51,6 +57,9 @@ type Entrypointer struct {
 	Runner Runner
 	// PostWriter encapsulates writing files when complete.
 	PostWriter PostWriter
+
+	// Results is the set of files that might contain task results
+	Results []string
 }
 
 // Waiter encapsulates waiting for files to exist.
@@ -100,12 +109,39 @@ func (e Entrypointer) Go() error {
 	// Write the post file *no matter what*
 	e.WritePostFile(e.PostFile, err)
 
+	if e.Results != nil {
+		if err := e.handleResultFiles(); err != nil {
+			logger.Fatalf("Error while handling results: %s", err)
+		}
+	}
 	if wErr := termination.WriteMessage(e.TerminationPath, output); wErr != nil {
 		logger.Fatalf("Error while writing message: %s", wErr)
 	}
 	return err
 }
 
+func (e Entrypointer) handleResultFiles() error {
+	output := []v1alpha1.PipelineResourceResult{}
+	for _, resultFile := range e.Results {
+		// check result file
+		fileContents, err := ioutil.ReadFile(DefaultResultPath + resultFile)
+		if err != nil {
+			return err
+		}
+		output = append(output, v1alpha1.PipelineResourceResult{
+			Key:        resultFile,
+			Value:      string(fileContents),
+			ResultType: "result",
+		})
+	}
+	// push output to termination path
+	if err := termination.WriteMessage(e.TerminationPath, output); err != nil {
+		return err
+	}
+	return nil
+}
+
+// WritePostFile write the postfile
 func (e Entrypointer) WritePostFile(postFile string, err error) {
 	if err != nil && postFile != "" {
 		postFile = fmt.Sprintf("%s.err", postFile)

pkg/pod/entrypoint.go

@@ -22,6 +22,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/tektoncd/pipeline/pkg/apis/pipeline/v1alpha1"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
@@ -85,7 +86,7 @@ var (
 // method, using entrypoint_lookup.go.
 //
 // TODO(#1605): Also use entrypoint injection to order sidecar start/stop.
-func orderContainers(entrypointImage string, steps []corev1.Container) (corev1.Container, []corev1.Container, error) {
+func orderContainers(entrypointImage string, steps []corev1.Container, results []v1alpha1.TaskResult) (corev1.Container, []corev1.Container, error) {
 	toolsInit := corev1.Container{
 		Name:         "place-tools",
 		Image:        entrypointImage,
@@ -109,6 +110,18 @@ func orderContainers(entrypointImage string, steps []corev1.Container) (corev1.C
 				"-post_file", filepath.Join(mountPoint, fmt.Sprintf("%d", i)),
 				"-termination_path", terminationPath,
 			}
+			if results != nil && len(steps) == 1 {
+				argsForEntrypoint = append(argsForEntrypoint, "-results", collectResultsName(results))
+			}
+		case len(steps) - 1:
+			argsForEntrypoint = []string{
+				"-wait_file", filepath.Join(mountPoint, fmt.Sprintf("%d", i-1)),
+				"-post_file", filepath.Join(mountPoint, fmt.Sprintf("%d", i)),
+				"-termination_path", terminationPath,
+			}
+			if results != nil {
+				argsForEntrypoint = append(argsForEntrypoint, "-results", collectResultsName(results))
+			}
 		default:
 			// All other steps wait for previous file, write next file.
 			argsForEntrypoint = []string{
@@ -140,6 +153,14 @@ func orderContainers(entrypointImage string, steps []corev1.Container) (corev1.C
 	return toolsInit, steps, nil
 }
 
+func collectResultsName(results []v1alpha1.TaskResult) string {
+	var resultNames []string
+	for _, r := range results {
+		resultNames = append(resultNames, r.Name)
+	}
+	return strings.Join(resultNames, ",")
+}
+
 // UpdateReady updates the Pod's annotations to signal the first step to start
 // by projecting the ready annotation via the Downward API.
 func UpdateReady(kubeclient kubernetes.Interface, pod corev1.Pod) error {

pkg/pod/entrypoint_test.go

@@ -21,6 +21,7 @@ import (
 	"time"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/tektoncd/pipeline/pkg/apis/pipeline/v1alpha1"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	fakek8s "k8s.io/client-go/kubernetes/fake"
@@ -85,7 +86,7 @@ func TestOrderContainers(t *testing.T) {
 		VolumeMounts:           []corev1.VolumeMount{toolsMount},
 		TerminationMessagePath: "/tekton/termination",
 	}}
-	gotInit, got, err := orderContainers(images.EntrypointImage, steps)
+	gotInit, got, err := orderContainers(images.EntrypointImage, steps, nil)
 	if err != nil {
 		t.Fatalf("orderContainers: %v", err)
 	}
@@ -104,6 +105,149 @@ func TestOrderContainers(t *testing.T) {
 	}
 }
 
+func TestEntryPointResults(t *testing.T) {
+	results := []v1alpha1.TaskResult{{
+		Name:        "sum",
+		Description: "This is the sum result of the task",
+	}, {
+		Name:        "sub",
+		Description: "This is the sub result of the task",
+	}}
+
+	steps := []corev1.Container{{
+		Image:   "step-1",
+		Command: []string{"cmd"},
+		Args:    []string{"arg1", "arg2"},
+	}, {
+		Image:        "step-2",
+		Command:      []string{"cmd1", "cmd2", "cmd3"}, // multiple cmd elements
+		Args:         []string{"arg1", "arg2"},
+		VolumeMounts: []corev1.VolumeMount{volumeMount}, // pre-existing volumeMount
+	}, {
+		Image:   "step-3",
+		Command: []string{"cmd"},
+		Args:    []string{"arg1", "arg2"},
+	}}
+	want := []corev1.Container{{
+		Image:   "step-1",
+		Command: []string{entrypointBinary},
+		Args: []string{
+			"-wait_file", "/tekton/downward/ready",
+			"-wait_file_content",
+			"-post_file", "/tekton/tools/0",
+			"-termination_path", "/tekton/termination",
+			"-entrypoint", "cmd", "--",
+			"arg1", "arg2",
+		},
+		VolumeMounts:           []corev1.VolumeMount{toolsMount, downwardMount},
+		TerminationMessagePath: "/tekton/termination",
+	}, {
+		Image:   "step-2",
+		Command: []string{entrypointBinary},
+		Args: []string{
+			"-wait_file", "/tekton/tools/0",
+			"-post_file", "/tekton/tools/1",
+			"-termination_path", "/tekton/termination",
+			"-entrypoint", "cmd1", "--",
+			"cmd2", "cmd3",
+			"arg1", "arg2",
+		},
+		VolumeMounts:           []corev1.VolumeMount{volumeMount, toolsMount},
+		TerminationMessagePath: "/tekton/termination",
+	}, {
+		Image:   "step-3",
+		Command: []string{entrypointBinary},
+		Args: []string{
+			"-wait_file", "/tekton/tools/1",
+			"-post_file", "/tekton/tools/2",
+			"-termination_path", "/tekton/termination",
+			"-results", "sum,sub",
+			"-entrypoint", "cmd", "--",
+			"arg1", "arg2",
+		},
+		VolumeMounts:           []corev1.VolumeMount{toolsMount},
+		TerminationMessagePath: "/tekton/termination",
+	}}
+	_, got, err := orderContainers(images.EntrypointImage, steps, results)
+	if err != nil {
+		t.Fatalf("orderContainers: %v", err)
+	}
+	if d := cmp.Diff(want, got); d != "" {
+		t.Errorf("Diff (-want, +got): %s", d)
+	}
+}
+
+func TestEntryPointResultsSingleStep(t *testing.T) {
+	results := []v1alpha1.TaskResult{{
+		Name:        "sum",
+		Description: "This is the sum result of the task",
+	}, {
+		Name:        "sub",
+		Description: "This is the sub result of the task",
+	}}
+
+	steps := []corev1.Container{{
+		Image:   "step-1",
+		Command: []string{"cmd"},
+		Args:    []string{"arg1", "arg2"},
+	}}
+	want := []corev1.Container{{
+		Image:   "step-1",
+		Command: []string{entrypointBinary},
+		Args: []string{
+			"-wait_file", "/tekton/downward/ready",
+			"-wait_file_content",
+			"-post_file", "/tekton/tools/0",
+			"-termination_path", "/tekton/termination",
+			"-results", "sum,sub",
+			"-entrypoint", "cmd", "--",
+			"arg1", "arg2",
+		},
+		VolumeMounts:           []corev1.VolumeMount{toolsMount, downwardMount},
+		TerminationMessagePath: "/tekton/termination",
+	}}
+	_, got, err := orderContainers(images.EntrypointImage, steps, results)
+	if err != nil {
+		t.Fatalf("orderContainers: %v", err)
+	}
+	if d := cmp.Diff(want, got); d != "" {
+		t.Errorf("Diff (-want, +got): %s", d)
+	}
+}
+func TestEntryPointSingleResultsSingleStep(t *testing.T) {
+	results := []v1alpha1.TaskResult{{
+		Name:        "sum",
+		Description: "This is the sum result of the task",
+	}}
+
+	steps := []corev1.Container{{
+		Image:   "step-1",
+		Command: []string{"cmd"},
+		Args:    []string{"arg1", "arg2"},
+	}}
+	want := []corev1.Container{{
+		Image:   "step-1",
+		Command: []string{entrypointBinary},
+		Args: []string{
+			"-wait_file", "/tekton/downward/ready",
+			"-wait_file_content",
+			"-post_file", "/tekton/tools/0",
+			"-termination_path", "/tekton/termination",
+			"-results", "sum",
+			"-entrypoint", "cmd", "--",
+			"arg1", "arg2",
+		},
+		VolumeMounts:           []corev1.VolumeMount{toolsMount, downwardMount},
+		TerminationMessagePath: "/tekton/termination",
+	}}
+	_, got, err := orderContainers(images.EntrypointImage, steps, results)
+	if err != nil {
+		t.Fatalf("orderContainers: %v", err)
+	}
+	if d := cmp.Diff(want, got); d != "" {
+		t.Errorf("Diff (-want, +got): %s", d)
+	}
+}
 func TestUpdateReady(t *testing.T) {
 	for _, c := range []struct {
 		desc            string

pkg/pod/pod.go

@@ -114,7 +114,7 @@ func MakePod(images pipeline.Images, taskRun *v1alpha1.TaskRun, taskSpec v1alpha
 
 	// Rewrite steps with entrypoint binary. Append the entrypoint init
 	// container to place the entrypoint binary.
-	entrypointInit, stepContainers, err := orderContainers(images.EntrypointImage, stepContainers)
+	entrypointInit, stepContainers, err := orderContainers(images.EntrypointImage, stepContainers, taskSpec.Results)
 	if err != nil {
 		return nil, err
 	}