Implement support for PNS (Process Namespace Sharing) executor

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## 2.3.0 (Not Yet Released)
+
+### Deprecation Notice
+The workflow-controller-configmap introduces a new config field, `executor`, which is a container 
+spec and provides controls over the executor sidecar container (i.e. `init`/`wait`). The fields
+`executorImage`, `executorResources`, and `executorImagePullPolicy` are deprecated and will be
+removed in a future release.
+
 ## 2.2.1 (2018-10-18)
 
 ### Changelog since v2.2.0

cmd/argoexec/commands/init.go

@@ -6,19 +6,18 @@ import (
 	"github.com/spf13/cobra"
 )
 
-func init() {
-	RootCmd.AddCommand(initCmd)
-}
-
-var initCmd = &cobra.Command{
-	Use:   "init",
-	Short: "Load artifacts",
-	Run: func(cmd *cobra.Command, args []string) {
-		err := loadArtifacts()
-		if err != nil {
-			log.Fatalf("%+v", err)
-		}
-	},
+func NewInitCommand() *cobra.Command {
+	var command = cobra.Command{
+		Use:   "init",
+		Short: "Load artifacts",
+		Run: func(cmd *cobra.Command, args []string) {
+			err := loadArtifacts()
+			if err != nil {
+				log.Fatalf("%+v", err)
+			}
+		},
+	}
+	return &command
 }
 
 func loadArtifacts() error {

cmd/argoexec/commands/resource.go

@@ -9,23 +9,22 @@ import (
 	"github.com/spf13/cobra"
 )
 
-func init() {
-	RootCmd.AddCommand(resourceCmd)
-}
-
-var resourceCmd = &cobra.Command{
-	Use:   "resource (get|create|apply|delete) MANIFEST",
-	Short: "update a resource and wait for resource conditions",
-	Run: func(cmd *cobra.Command, args []string) {
-		if len(args) != 1 {
-			cmd.HelpFunc()(cmd, args)
-			os.Exit(1)
-		}
-		err := execResource(args[0])
-		if err != nil {
-			log.Fatalf("%+v", err)
-		}
-	},
+func NewResourceCommand() *cobra.Command {
+	var command = cobra.Command{
+		Use:   "resource (get|create|apply|delete) MANIFEST",
+		Short: "update a resource and wait for resource conditions",
+		Run: func(cmd *cobra.Command, args []string) {
+			if len(args) != 1 {
+				cmd.HelpFunc()(cmd, args)
+				os.Exit(1)
+			}
+			err := execResource(args[0])
+			if err != nil {
+				log.Fatalf("%+v", err)
+			}
+		},
+	}
+	return &command
 }
 
 func execResource(action string) error {

cmd/argoexec/commands/root.go

@@ -1,10 +1,11 @@
 package commands
 
 import (
+	"encoding/json"
 	"os"
 
-	"github.com/argoproj/pkg/kube/cli"
-	"github.com/ghodss/yaml"
+	"github.com/argoproj/pkg/cli"
+	kubecli "github.com/argoproj/pkg/kube/cli"
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	"k8s.io/client-go/kubernetes"
@@ -17,6 +18,7 @@ import (
 	"github.com/argoproj/argo/workflow/executor/docker"
 	"github.com/argoproj/argo/workflow/executor/k8sapi"
 	"github.com/argoproj/argo/workflow/executor/kubelet"
+	"github.com/argoproj/argo/workflow/executor/pns"
 )
 
 const (
@@ -25,83 +27,82 @@ const (
 )
 
 var (
-	// GlobalArgs hold global CLI flags
-	GlobalArgs globalFlags
-
-	clientConfig clientcmd.ClientConfig
-)
-
-type globalFlags struct {
+	clientConfig       clientcmd.ClientConfig
+	logLevel           string // --loglevel
+	glogLevel          int    // --gloglevel
 	podAnnotationsPath string // --pod-annotations
-}
+)
 
 func init() {
-	clientConfig = cli.AddKubectlFlagsToCmd(RootCmd)
-	RootCmd.PersistentFlags().StringVar(&GlobalArgs.podAnnotationsPath, "pod-annotations", common.PodMetadataAnnotationsPath, "Pod annotations file from k8s downward API")
-	RootCmd.AddCommand(cmd.NewVersionCmd(CLIName))
+	cobra.OnInitialize(initConfig)
 }
 
-// RootCmd is the argo root level command
-var RootCmd = &cobra.Command{
-	Use:   CLIName,
-	Short: "argoexec is the executor sidecar to workflow containers",
-	Run: func(cmd *cobra.Command, args []string) {
-		cmd.HelpFunc()(cmd, args)
-	},
+func initConfig() {
+	cli.SetLogLevel(logLevel)
+	cli.SetGLogLevel(glogLevel)
 }
 
-func initExecutor() *executor.WorkflowExecutor {
-	podAnnotationsPath := common.PodMetadataAnnotationsPath
-
-	// Use the path specified from the flag
-	if GlobalArgs.podAnnotationsPath != "" {
-		podAnnotationsPath = GlobalArgs.podAnnotationsPath
+func NewRootCommand() *cobra.Command {
+	var command = cobra.Command{
+		Use:   CLIName,
+		Short: "argoexec is the executor sidecar to workflow containers",
+		Run: func(cmd *cobra.Command, args []string) {
+			cmd.HelpFunc()(cmd, args)
+		},
 	}
 
+	command.AddCommand(NewInitCommand())
+	command.AddCommand(NewResourceCommand())
+	command.AddCommand(NewWaitCommand())
+	command.AddCommand(cmd.NewVersionCmd(CLIName))
+
+	clientConfig = kubecli.AddKubectlFlagsToCmd(&command)
+	command.PersistentFlags().StringVar(&podAnnotationsPath, "pod-annotations", common.PodMetadataAnnotationsPath, "Pod annotations file from k8s downward API")
+	command.PersistentFlags().StringVar(&logLevel, "loglevel", "info", "Set the logging level. One of: debug|info|warn|error")
+	command.PersistentFlags().IntVar(&glogLevel, "gloglevel", 0, "Set the glog logging level")
+
+	return &command
+}
+
+func initExecutor() *executor.WorkflowExecutor {
 	config, err := clientConfig.ClientConfig()
-	if err != nil {
-		panic(err.Error())
-	}
+	checkErr(err)
+
 	namespace, _, err := clientConfig.Namespace()
-	if err != nil {
-		panic(err.Error())
-	}
+	checkErr(err)
 
 	clientset, err := kubernetes.NewForConfig(config)
-	if err != nil {
-		panic(err.Error())
-	}
-	podName, ok := os.LookupEnv(common.EnvVarPodName)
-	if !ok {
-		log.Fatalf("Unable to determine pod name from environment variable %s", common.EnvVarPodName)
-	}
+	checkErr(err)
+
+	podName, err := os.Hostname()
+	checkErr(err)
+
+	tmpl, err := executor.LoadTemplate(podAnnotationsPath)
+	checkErr(err)
 
 	var cre executor.ContainerRuntimeExecutor
 	switch os.Getenv(common.EnvVarContainerRuntimeExecutor) {
 	case common.ContainerRuntimeExecutorK8sAPI:
 		cre, err = k8sapi.NewK8sAPIExecutor(clientset, config, podName, namespace)
-		if err != nil {
-			panic(err.Error())
-		}
 	case common.ContainerRuntimeExecutorKubelet:
 		cre, err = kubelet.NewKubeletExecutor()
-		if err != nil {
-			panic(err.Error())
-		}
+	case common.ContainerRuntimeExecutorPNS:
+		cre, err = pns.NewPNSExecutor(clientset, podName, namespace, tmpl.Outputs.HasOutputs())
 	default:
 		cre, err = docker.NewDockerExecutor()
-		if err != nil {
-			panic(err.Error())
-		}
-	}
-	wfExecutor := executor.NewExecutor(clientset, podName, namespace, podAnnotationsPath, cre)
-	err = wfExecutor.LoadTemplate()
-	if err != nil {
-		panic(err.Error())
 	}
+	checkErr(err)
 
-	yamlBytes, _ := yaml.Marshal(&wfExecutor.Template)
+	wfExecutor := executor.NewExecutor(clientset, podName, namespace, podAnnotationsPath, cre, *tmpl)
+	yamlBytes, _ := json.Marshal(&wfExecutor.Template)
 	vers := argo.GetVersion()
 	log.Infof("Executor (version: %s, build_date: %s) initialized with template:\n%s", vers, vers.BuildDate, string(yamlBytes))
 	return &wfExecutor
 }
+
+// checkErr is a convenience function to panic upon error
+func checkErr(err error) {
+	if err != nil {
+		panic(err.Error())
+	}
+}

cmd/argoexec/commands/wait.go

@@ -8,19 +8,18 @@ import (
 	"github.com/spf13/cobra"
 )
 
-func init() {
-	RootCmd.AddCommand(waitCmd)
-}
-
-var waitCmd = &cobra.Command{
-	Use:   "wait",
-	Short: "wait for main container to finish and save artifacts",
-	Run: func(cmd *cobra.Command, args []string) {
-		err := waitContainer()
-		if err != nil {
-			log.Fatalf("%+v", err)
-		}
-	},
+func NewWaitCommand() *cobra.Command {
+	var command = cobra.Command{
+		Use:   "wait",
+		Short: "wait for main container to finish and save artifacts",
+		Run: func(cmd *cobra.Command, args []string) {
+			err := waitContainer()
+			if err != nil {
+				log.Fatalf("%+v", err)
+			}
+		},
+	}
+	return &command
 }
 
 func waitContainer() error {
@@ -29,11 +28,16 @@ func waitContainer() error {
 	defer stats.LogStats()
 	stats.StartStatsTicker(5 * time.Minute)
 
-	// Wait for main container to complete and kill sidecars
+	// Wait for main container to complete
 	err := wfExecutor.Wait()
 	if err != nil {
 		wfExecutor.AddError(err)
-		// do not return here so we can still try to save outputs
+		// do not return here so we can still try to kill sidecars & save outputs
+	}
+	err = wfExecutor.KillSidecars()
+	if err != nil {
+		wfExecutor.AddError(err)
+		// do not return here so we can still try save outputs
 	}
 	logArt, err := wfExecutor.SaveLogs()
 	if err != nil {

cmd/argoexec/main.go

@@ -14,7 +14,7 @@ import (
 )
 
 func main() {
-	if err := commands.RootCmd.Execute(); err != nil {
+	if err := commands.NewRootCommand().Execute(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}