Add support for performing server-side applies (#191)

DOCS.md

@@ -565,6 +565,29 @@ steps:
       # ...
 ```
 
+### `server_side`
+
+_**type**_ `bool`
+
+_**default**_ `false`
+
+_**description**_ Perform a Kubernetes [server-side apply](https://kubernetes.io/docs/reference/using-api/server-side-apply/)
+
+_**example**_
+
+```yaml
+# .drone.yml
+---
+kind: pipeline
+# ...
+steps:
+  - name: deploy-gke
+    image: nytimes/drone-gke
+    settings:
+      server_side: true
+      # ...
+```
+
 ### `verbose`
 
 _**type**_ `bool`

Makefile

@@ -201,6 +201,7 @@ run :
 	@$(docker) run \
 		--env PLUGIN_CLUSTER \
 		--env PLUGIN_DRY_RUN \
+		--env PLUGIN_SERVER_SIDE \
 		--env PLUGIN_EXPAND_ENV_VARS \
 		--env PLUGIN_KUBECTL_VERSION \
 		--env PLUGIN_NAMESPACE \

main.go

@@ -39,8 +39,11 @@ const (
 	nsPath           = "/tmp/namespace.json"
 	templateBasePath = "/tmp"
 
-	dryRunFlagPre118  = "--dry-run=true"
-	dryRunFlagDefault = "--dry-run=client"
+	clientSideDryRunFlagPre118  = "--dry-run=true"
+	clientSideDryRunFlagDefault = "--dry-run=client"
+	serverSideDryRunFlagPre118  = "--server-dry-run=true"
+	serverSideDryRunFlagDefault = "--dry-run=server"
+	serverSideApplyFlag         = "--server-side"
 )
 
 // default to kubectlCmdName, can be overriden via kubectl-version param
@@ -54,7 +57,7 @@ metadata:
   name: %s
 `
 var invalidNameRegex = regexp.MustCompile(`[^a-z0-9\.\-]+`)
-var dryRunFlag = dryRunFlagDefault
+var dryRunFlag = clientSideDryRunFlagDefault
 
 func main() {
 	err := wrapMain()
@@ -71,6 +74,11 @@ func getAppFlags() []cli.Flag {
 			Usage:   "do not apply the Kubernetes manifests to the API server",
 			EnvVars: []string{"PLUGIN_DRY_RUN"},
 		},
+		&cli.BoolFlag{
+			Name:    "server-side",
+			Usage:   "perform a server-side apply",
+			EnvVars: []string{"PLUGIN_SERVER_SIDE"},
+		},
 		&cli.BoolFlag{
 			Name:    "verbose",
 			Usage:   "dump available vars and the generated Kubernetes manifest, keeping secrets hidden",
@@ -248,7 +256,7 @@ func run(c *cli.Context) error {
 	// Parse and adjust the dry-run flag if needed
 	var dryRunBuffer bytes.Buffer
 	dryRunRunner := NewBasicRunner("/", []string{}, &dryRunBuffer, &dryRunBuffer)
-	if err := setDryRunFlag(dryRunRunner, &dryRunBuffer); err != nil {
+	if err := setDryRunFlag(dryRunRunner, &dryRunBuffer, c); err != nil {
 		return err
 	}
 
@@ -337,7 +345,7 @@ func run(c *cli.Context) error {
 	}
 
 	// Wait for jobs to finish
-	if err:= waitForJobs(c, runner); err != nil {
+	if err := waitForJobs(c, runner); err != nil {
 		return fmt.Errorf("Error: %s\n", err)
 	}
 
@@ -438,18 +446,31 @@ func parseSkips(c *cli.Context) error {
 	return nil
 }
 
-// setDryRunFlag sets the value of the dry-run flag for the version of kubectl
-// that is being used
-func setDryRunFlag(runner Runner, output io.Reader) error {
-	dryRunFlag = dryRunFlagDefault
+// setDryRunFlag sets the value of the dry-run flag based on the version of kubectl being
+// used and whether the apply should be client-side or server-side
+func setDryRunFlag(runner Runner, output io.Reader, c *cli.Context) error {
+	dryRunFlag = clientSideDryRunFlagDefault
+
 	version, err := getMinorVersion(runner, output)
 	if err != nil {
 		return fmt.Errorf("Error determining which kubectl version is running: %v", err)
 	}
-	// default is the >= 1.18 flag
-	if version < 18 {
-		dryRunFlag = dryRunFlagPre118
+
+	isServerSideApply := c.Bool("server-side")
+
+	// Default is the >= 1.18 flag for both server- and client-side dry runs
+	if isServerSideApply {
+		if version < 18 {
+			dryRunFlag = serverSideDryRunFlagPre118
+		} else {
+			dryRunFlag = serverSideDryRunFlagDefault
+		}
+	} else {
+		if version < 18 {
+			dryRunFlag = clientSideDryRunFlagPre118
+		}
 	}
+
 	return nil
 }
 
@@ -746,7 +767,7 @@ func setNamespace(c *cli.Context, project string, runner Runner) error {
 	// Ensure the namespace exists, without errors (unlike `kubectl create namespace`).
 	log("Ensuring the %s namespace exists\n", namespace)
 
-	nsArgs := applyArgs(c.Bool("dry-run"), nsPath)
+	nsArgs := applyArgs(c.Bool("dry-run"), c.Bool("server-side"), nsPath)
 	if err := runner.Run(kubectlCmd, nsArgs...); err != nil {
 		return fmt.Errorf("Error: %s\n", err)
 	}
@@ -764,13 +785,13 @@ func applyManifests(c *cli.Context, manifestPaths map[string]string, runner Runn
 	log("Validating Kubernetes manifests with a dry-run\n")
 
 	if !c.Bool("dry-run") {
-		args := applyArgs(true, manifests)
+		args := applyArgs(true, c.Bool("server-side"), manifests)
 		if err := runner.Run(kubectlCmd, args...); err != nil {
 			return fmt.Errorf("Error: %s\n", err)
 		}
 
 		if len(manifestsSecret) > 0 {
-			argsSecret := applyArgs(true, manifestsSecret)
+			argsSecret := applyArgs(true, c.Bool("server-side"), manifestsSecret)
 			if err := runnerSecret.Run(kubectlCmd, argsSecret...); err != nil {
 				return fmt.Errorf("Error: %s\n", err)
 			}
@@ -780,14 +801,14 @@ func applyManifests(c *cli.Context, manifestPaths map[string]string, runner Runn
 	}
 
 	// Actually apply Kubernetes manifests.
-	args := applyArgs(c.Bool("dry-run"), manifests)
+	args := applyArgs(c.Bool("dry-run"), c.Bool("server-side"), manifests)
 	if err := runner.Run(kubectlCmd, args...); err != nil {
 		return fmt.Errorf("Error: %s\n", err)
 	}
 
 	// Apply Kubernetes secrets manifests
 	if len(manifestsSecret) > 0 {
-		argsSecret := applyArgs(c.Bool("dry-run"), manifestsSecret)
+		argsSecret := applyArgs(c.Bool("dry-run"), c.Bool("server-side"), manifestsSecret)
 		if err := runnerSecret.Run(kubectlCmd, argsSecret...); err != nil {
 			return fmt.Errorf("Error: %s\n", err)
 		}
@@ -868,7 +889,7 @@ func waitForJobs(c *cli.Context, runner Runner) error {
 		log(fmt.Sprintf("Waiting until job completes for %s%s\n", job, counterProgress))
 
 		command := []string{"wait", "--for=condition=complete", job}
-		
+
 		if waitSeconds != 0 {
 			command = append(command, fmt.Sprintf("--timeout=%ds", waitSeconds))
 		}
@@ -888,7 +909,7 @@ func waitForJobs(c *cli.Context, runner Runner) error {
 }
 
 // applyArgs creates args slice for kubectl apply command
-func applyArgs(dryrun bool, file string) []string {
+func applyArgs(dryrun bool, serverSide bool, file string) []string {
 	args := []string{
 		"apply",
 	}
@@ -897,6 +918,10 @@ func applyArgs(dryrun bool, file string) []string {
 		args = append(args, dryRunFlag)
 	}
 
+	if serverSide {
+		args = append(args, serverSideApplyFlag)
+	}
+
 	args = append(args, "--filename")
 	args = append(args, file)
 

main_test.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"strconv"
 	"strings"
 	"testing"
 
@@ -632,11 +633,14 @@ func TestWaitForJobs(t *testing.T) {
 }
 
 func TestApplyArgs(t *testing.T) {
-	args := applyArgs(false, "/path/to/file/1")
+	args := applyArgs(false, false, "/path/to/file/1")
 	assert.Equal(t, []string{"apply", "--filename", "/path/to/file/1"}, args)
 
-	args = applyArgs(true, "/path/to/file/2")
+	args = applyArgs(true, false, "/path/to/file/2")
 	assert.Equal(t, []string{"apply", "--dry-run=client", "--filename", "/path/to/file/2"}, args)
+
+	args = applyArgs(false, true, "/path/to/file/3")
+	assert.Equal(t, []string{"apply", "--server-side", "--filename", "/path/to/file/3"}, args)
 }
 
 func TestPrintTrimmedError(t *testing.T) {
@@ -736,6 +740,7 @@ func TestSetDryRunFlag(t *testing.T) {
 		name                 string
 		versionCommandOutput string
 		explicitVersion      string
+		isServerSide         bool
 
 		expectedFlag string
 	}{
@@ -755,7 +760,7 @@ func TestSetDryRunFlag(t *testing.T) {
 				}
 			}`,
 			explicitVersion: "",
-			expectedFlag:    dryRunFlagPre118,
+			expectedFlag:    clientSideDryRunFlagPre118,
 		},
 		{
 			name: "kubectl-1.15",
@@ -773,7 +778,7 @@ func TestSetDryRunFlag(t *testing.T) {
 				}
 			}`,
 			explicitVersion: "1.15",
-			expectedFlag:    dryRunFlagPre118,
+			expectedFlag:    clientSideDryRunFlagPre118,
 		},
 		{
 			name: "kubectl-1.16",
@@ -791,7 +796,25 @@ func TestSetDryRunFlag(t *testing.T) {
 				}
 			}`,
 			explicitVersion: "1.16",
-			expectedFlag:    dryRunFlagPre118,
+			expectedFlag:    clientSideDryRunFlagPre118,
+		},
+		{
+			name: "kubectl-1.17",
+			versionCommandOutput: `{
+				"clientVersion": {
+					"major": "1",
+					"minor": "17",
+					"gitVersion": "v1.17.17",
+					"gitCommit": "f3abc15296f3a3f54e4ee42e830c61047b13895f",
+					"gitTreeState": "clean",
+					"buildDate": "2021-01-13T13:21:12Z",
+					"goVersion": "go1.13.15",
+					"compiler": "gc",
+					"platform": "linux/amd64"
+				}
+			}`,
+			explicitVersion: "1.17",
+			expectedFlag:    clientSideDryRunFlagPre118,
 		},
 		{
 			name: "kubectl-1.17",
@@ -809,7 +832,26 @@ func TestSetDryRunFlag(t *testing.T) {
 				}
 			}`,
 			explicitVersion: "1.17",
-			expectedFlag:    dryRunFlagPre118,
+			isServerSide:    true,
+			expectedFlag:    serverSideDryRunFlagPre118,
+		},
+		{
+			name: "kubectl-1.18",
+			versionCommandOutput: `{
+				"clientVersion": {
+					"major": "1",
+					"minor": "18",
+					"gitVersion": "v1.18.15",
+					"gitCommit": "73dd5c840662bb066a146d0871216333181f4b64",
+					"gitTreeState": "clean",
+					"buildDate": "2021-01-13T13:22:41Z",
+					"goVersion": "go1.13.15",
+					"compiler": "gc",
+					"platform": "linux/amd64"
+				}
+			}`,
+			explicitVersion: "1.18",
+			expectedFlag:    clientSideDryRunFlagDefault,
 		},
 		{
 			name: "kubectl-1.18",
@@ -827,7 +869,8 @@ func TestSetDryRunFlag(t *testing.T) {
 				}
 			}`,
 			explicitVersion: "1.18",
-			expectedFlag:    dryRunFlagDefault,
+			isServerSide:    true,
+			expectedFlag:    serverSideDryRunFlagDefault,
 		},
 		{
 			name: "kubectl-1.19",
@@ -845,14 +888,15 @@ func TestSetDryRunFlag(t *testing.T) {
 				}
 			}`,
 			explicitVersion: "1.19",
-			expectedFlag:    dryRunFlagDefault,
+			expectedFlag:    clientSideDryRunFlagDefault,
 		},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
 			os.Clearenv()
 
 			os.Setenv("PLUGIN_KUBECTL_VERSION", test.explicitVersion)
+			os.Setenv("PLUGIN_SERVER_SIDE", strconv.FormatBool(test.isServerSide))
 
 			err := (&cli.App{
 				Flags: getAppFlags(),
@@ -874,7 +918,7 @@ func TestSetDryRunFlag(t *testing.T) {
 					}
 
 					// Run
-					setDryRunFlag(testRunner, buf)
+					setDryRunFlag(testRunner, buf, ctx)
 
 					// Check
 					if dryRunFlag != test.expectedFlag {