Merge pull request #991 from dgageot/print-kubectl-version

Print kubectl client version

pkg/skaffold/deploy/kubectl.go

@@ -25,6 +25,7 @@ import (
 	"strings"
 
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/build"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/color"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/constants"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/deploy/kubectl"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/v1alpha3"
@@ -64,6 +65,8 @@ func (k *KubectlDeployer) Labels() map[string]string {
 // Deploy templates the provided manifests with a simple `find and replace` and
 // runs `kubectl apply` on those manifests
 func (k *KubectlDeployer) Deploy(ctx context.Context, out io.Writer, builds []build.Artifact) ([]Artifact, error) {
+	color.Default.Fprintln(out, "kubectl client version:", k.kubectl.Version())
+
 	manifests, err := k.readManifests(ctx)
 	if err != nil {
 		return nil, errors.Wrap(err, "reading manifests")

pkg/skaffold/deploy/kubectl/cli.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"io"
 	"os/exec"
+	"sync"
 
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/v1alpha3"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/util"
@@ -33,6 +34,8 @@ type CLI struct {
 	KubeContext string
 	Flags       v1alpha3.KubectlFlags
 
+	version       ClientVersion
+	versionOnce   sync.Once
 	previousApply ManifestList
 }
 

pkg/skaffold/deploy/kubectl/version.go

@@ -0,0 +1,75 @@
+/*
+Copyright 2018 The Skaffold 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 kubectl
+
+import (
+	"context"
+	"encoding/json"
+	"os/exec"
+
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/util"
+	"github.com/sirupsen/logrus"
+)
+
+const unknown = "unknown"
+
+// Version is the client version of kubectl.
+type Version struct {
+	Client ClientVersion `json:"clientVersion"`
+}
+
+// ClientVersion is the client version of kubectl.
+type ClientVersion struct {
+	Major string `json:"major"`
+	Minor string `json:"minor"`
+}
+
+func (v ClientVersion) String() string {
+	if v.Major == unknown || v.Minor == unknown {
+		return unknown
+	}
+
+	return v.Major + "." + v.Minor
+}
+
+// Version returns the client version of kubectl.
+func (c *CLI) Version() ClientVersion {
+	c.versionOnce.Do(func() {
+		version := Version{
+			Client: ClientVersion{
+				Major: unknown,
+				Minor: unknown,
+			},
+		}
+
+		buf, err := c.getVersion(context.Background())
+		if err != nil {
+			logrus.Warnln("unable to get kubectl client version", err)
+		} else if err := json.Unmarshal(buf, &version); err != nil {
+			logrus.Warnln("unable to parse client version", err)
+		}
+
+		c.version = version.Client
+	})
+
+	return c.version
+}
+
+func (c *CLI) getVersion(ctx context.Context) ([]byte, error) {
+	cmd := exec.CommandContext(ctx, "kubectl", "version", "--client", "-ojson")
+	return util.RunCmdOut(cmd)
+}