exec target command, but still pipe it to tee

Equivalent of https://github.com/kubernetes/kubernetes/pull/57756

nodeup/pkg/model/convenience.go

@@ -21,14 +21,14 @@ import (
 	"path/filepath"
 	"sort"
 	"strconv"
+	"strings"
 
+	"github.com/golang/glog"
 	"k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/kops/pkg/apis/kops"
 	"k8s.io/kops/upup/pkg/fi"
 	"k8s.io/kops/upup/pkg/fi/nodeup/nodetasks"
-
-	"github.com/golang/glog"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 // s is a helper that builds a *string from a string value
@@ -187,3 +187,19 @@ func addHostPathMapping(pod *v1.Pod, container *v1.Container, name, path string)
 func convEtcdSettingsToMs(dur *metav1.Duration) string {
 	return strconv.FormatInt(dur.Nanoseconds()/1000000, 10)
 }
+
+// execWithTee returns the command to run the command while piping output to both the log file and stdout/stderr
+func execWithTee(cmd string, args []string, logfile string) []string {
+	// exec so we don't have a shell that doesn't pass signals to the real process
+	execCmd := "exec " + cmd + " " + strings.Join(args, " ")
+
+	// NOTE: tee & mkfifo is in /usr/bin in the kube-proxy image, but /bin in other images
+
+	// Bash supports something like this, but dash and other limited shells don't
+	//shCmd := "exec &> >(/usr/bin/tee -a " + logfile + "); " + execCmd
+	// Instead we create the pipe manually and wire up the tee:
+	shCmd := "mkfifo /tmp/pipe; (tee -a " + logfile + " < /tmp/pipe & ) ; " + execCmd + " > /tmp/pipe 2>&1"
+
+	// Execute shell command
+	return []string{"/bin/sh", "-c", shCmd}
+}

nodeup/pkg/model/kube_apiserver.go

@@ -247,10 +247,10 @@ func (b *KubeAPIServerBuilder) buildPod() (*v1.Pod, error) {
 	container := &v1.Container{
 		Name:  "kube-apiserver",
 		Image: b.Cluster.Spec.KubeAPIServer.Image,
-		Command: []string{
-			"/bin/sh", "-c",
-			"/usr/local/bin/kube-apiserver " + strings.Join(sortedStrings(flags), " ") + " 2>&1 | /bin/tee -a /var/log/kube-apiserver.log",
-		},
+		Command: execWithTee(
+			"/usr/local/bin/kube-apiserver",
+			sortedStrings(flags),
+			"/var/log/kube-apiserver.log"),
 		Env: getProxyEnvVars(b.Cluster.Spec.EgressProxy),
 		LivenessProbe: &v1.Probe{
 			Handler: v1.Handler{

nodeup/pkg/model/kube_controller_manager.go

@@ -167,10 +167,10 @@ func (b *KubeControllerManagerBuilder) buildPod() (*v1.Pod, error) {
 	container := &v1.Container{
 		Name:  "kube-controller-manager",
 		Image: b.Cluster.Spec.KubeControllerManager.Image,
-		Command: []string{
-			"/bin/sh", "-c",
-			"/usr/local/bin/kube-controller-manager " + strings.Join(sortedStrings(flags), " ") + " 2>&1 | /bin/tee -a /var/log/kube-controller-manager.log",
-		},
+		Command: execWithTee(
+			"/usr/local/bin/kube-controller-manager",
+			sortedStrings(flags),
+			"/var/log/kube-controller-manager.log"),
 		Env: getProxyEnvVars(b.Cluster.Spec.EgressProxy),
 		LivenessProbe: &v1.Probe{
 			Handler: v1.Handler{

nodeup/pkg/model/kube_proxy.go

@@ -18,7 +18,6 @@ package model
 
 import (
 	"fmt"
-	"strings"
 
 	"k8s.io/kops/pkg/dns"
 	"k8s.io/kops/pkg/flagbuilder"
@@ -144,10 +143,10 @@ func (b *KubeProxyBuilder) buildPod() (*v1.Pod, error) {
 	container := &v1.Container{
 		Name:  "kube-proxy",
 		Image: image,
-		Command: []string{
-			"/bin/sh", "-c",
-			"/usr/local/bin/kube-proxy " + strings.Join(sortedStrings(flags), " ") + " 2>&1 | /usr/bin/tee -a /var/log/kube-proxy.log",
-		},
+		Command: execWithTee(
+			"/usr/local/bin/kube-proxy",
+			sortedStrings(flags),
+			"/var/log/kube-proxy.log"),
 		Resources: v1.ResourceRequirements{
 			Requests: v1.ResourceList{
 				"cpu": cpuRequest,

nodeup/pkg/model/kube_scheduler.go

@@ -18,7 +18,6 @@ package model
 
 import (
 	"fmt"
-	"strings"
 
 	"k8s.io/kops/pkg/flagbuilder"
 	"k8s.io/kops/upup/pkg/fi"
@@ -125,10 +124,10 @@ func (b *KubeSchedulerBuilder) buildPod() (*v1.Pod, error) {
 	container := &v1.Container{
 		Name:  "kube-scheduler",
 		Image: c.Image,
-		Command: []string{
-			"/bin/sh", "-c",
-			"/usr/local/bin/kube-scheduler " + strings.Join(sortedStrings(flags), " ") + " 2>&1 | /bin/tee -a /var/log/kube-scheduler.log",
-		},
+		Command: execWithTee(
+			"/usr/local/bin/kube-scheduler",
+			sortedStrings(flags),
+			"/var/log/kube-scheduler.log"),
 		Env: getProxyEnvVars(b.Cluster.Spec.EgressProxy),
 		LivenessProbe: &v1.Probe{
 			Handler: v1.Handler{

protokube/pkg/protokube/etcd_manifest.go

@@ -45,7 +45,10 @@ func BuildEtcdManifest(c *EtcdCluster) *v1.Pod {
 				},
 			},
 			Command: []string{
-				"/bin/sh", "-c", "/usr/local/bin/etcd 2>&1 | /bin/tee -a /var/log/etcd.log",
+				"/bin/sh", "-c",
+				"/bin/mkfifo /tmp/pipe; " +
+					"(/bin/tee -a /var/log/etcd.log < /tmp/pipe & ); " +
+					"exec /usr/local/bin/etcd > /tmp/pipe 2>&1",
 			},
 		}
 		// build the environment variables for etcd service

protokube/tests/integration/build_etcd_manifest/main/etcd_env_vars.yaml

@@ -37,7 +37,8 @@ spec:
   - command:
     - /bin/sh
     - -c
-    - /usr/local/bin/etcd 2>&1 | /bin/tee -a /var/log/etcd.log
+    - /bin/mkfifo /tmp/pipe; (/bin/tee -a /var/log/etcd.log < /tmp/pipe & ); exec
+      /usr/local/bin/etcd > /tmp/pipe 2>&1
     env:
     - name: ETCD_NAME
       value: node0

protokube/tests/integration/build_etcd_manifest/main/non_tls.yaml

@@ -35,7 +35,8 @@ spec:
   - command:
     - /bin/sh
     - -c
-    - /usr/local/bin/etcd 2>&1 | /bin/tee -a /var/log/etcd.log
+    - /bin/mkfifo /tmp/pipe; (/bin/tee -a /var/log/etcd.log < /tmp/pipe & ); exec
+      /usr/local/bin/etcd > /tmp/pipe 2>&1
     env:
     - name: ETCD_NAME
       value: node0

protokube/tests/integration/build_etcd_manifest/main/tls.yaml

@@ -41,7 +41,8 @@ spec:
   - command:
     - /bin/sh
     - -c
-    - /usr/local/bin/etcd 2>&1 | /bin/tee -a /var/log/etcd.log
+    - /bin/mkfifo /tmp/pipe; (/bin/tee -a /var/log/etcd.log < /tmp/pipe & ); exec
+      /usr/local/bin/etcd > /tmp/pipe 2>&1
     env:
     - name: ETCD_NAME
       value: node0