DV-12285: add create-namespace parameter (#155)

.drone.yml

@@ -22,7 +22,7 @@ slack_config: &slack_config
   image: plugins/slack
   pull: if-not-exists
   settings:
-    channel: dv-notifications
+    channel: dv-cicd
   environment:
     SLACK_WEBHOOK:
       from_secret: slack_webhook

DOCS.md

@@ -154,6 +154,30 @@ steps:
       # ...
 ```
 
+### `namespace`
+
+_**type**_ `string`
+
+_**default**_ `''`
+
+_**description**_ name of Kubernetes Namespace where manifests will be applied
+
+_**notes**_ if not specified, resources will be applied to `default` Namespace; if specified and [`create_namespace`](#create_namespace) is set to `false`, the Namespace resource must already exist within the cluster
+
+_**example**_
+
+```yaml
+# .drone.yml
+---
+pipeline:
+  # ...
+  deploy:
+    image: nytimes/drone-gke
+    cluster: prod
+    namespace: petstore
+    # ...
+```
+
 ### `template`
 
 _**type**_ `string`
@@ -511,6 +535,30 @@ steps:
       # ...
 ```
 
+### `create_namespace`
+
+_**type**_ `bool`
+
+_**default**_ `true`
+
+_**description**_ automatically create a Namespace resource when a [`namespace`](#namespace) value is specified
+
+_**notes**_ depends on non-empty `namespace` value; the resource will _always_ be applied to the cluster _prior to_ any resources included in [`template`](#template) / [`secret_template`](#secret_template); may modify any existing Namespace resource configuration; the automatically created Namespace resource is not configurable (see [source](https://github.com/nytimes/drone-gke/blob/2909135b2dce136aa5095d609d91b0963fbb4697/main.go#L51-L54) for more details);
+
+_**example**_
+
+```yaml
+# .drone.yml
+---
+pipeline:
+  # ...
+  deploy:
+    image: nytimes/drone-gke
+    namespace: petstore
+    create_namespace: false
+    # ...
+```
+
 ## Service Account Credentials
 
 `drone-gke` requires a Google service account and uses its [JSON credential file][service-account] to authenticate.

Makefile

@@ -143,7 +143,7 @@ $(coverage_name) : export GO111MODULE ?= on
 $(coverage_name) : export GOPROXY ?= https://proxy.golang.org
 
 # test binary
-$(coverage_name) : $(binary_name)
+$(coverage_name) : $(binary_name) dump_test.go exec_test.go main_test.go
 	@$(go) test -cover -vet all -coverprofile=$@
 
 .PHONY : test-coverage

main.go

@@ -106,6 +106,12 @@ func getAppFlags() []cli.Flag {
 			Usage:   "Kubernetes namespace to operate in",
 			EnvVars: []string{"PLUGIN_NAMESPACE"},
 		},
+		&cli.BoolFlag{
+			Name:    "create-namespace",
+			Usage:   "automatically create a Namespace resource when a 'namespace' value is specified",
+			EnvVars: []string{"PLUGIN_CREATE_NAMESPACE"},
+			Value:   true,
+		},
 		&cli.StringFlag{
 			Name:    "kube-template",
 			Usage:   "template for Kubernetes resources, e.g. Deployments",
@@ -710,6 +716,10 @@ func setNamespace(c *cli.Context, project string, runner Runner) error {
 		return fmt.Errorf("Error: %s\n", err)
 	}
 
+	if !c.Bool("create-namespace") {
+		return nil
+	}
+
 	// Write the namespace manifest to a tmp file for application.
 	resource := fmt.Sprintf(nsTemplate, namespace)
 

main_test.go

@@ -447,6 +447,7 @@ func TestSetNamespace(t *testing.T) {
 	set.String("cluster", "cluster-0", "")
 	set.String("namespace", "test-ns", "")
 	set.Bool("dry-run", false, "")
+	set.Bool("create-namespace", true, "")
 	c := cli.NewContext(nil, set, nil)
 
 	testRunner := new(MockedRunner)
@@ -462,6 +463,7 @@ func TestSetNamespace(t *testing.T) {
 	set.String("cluster", "regional-cluster", "")
 	set.String("namespace", "test-ns", "")
 	set.Bool("dry-run", false, "")
+	set.Bool("create-namespace", true, "")
 	c = cli.NewContext(nil, set, nil)
 
 	testRunner = new(MockedRunner)
@@ -481,6 +483,7 @@ func TestSetNamespace(t *testing.T) {
 	set.String("cluster", "cluster-0", "")
 	set.String("namespace", "Feature/1892-TEST-NS", "")
 	set.Bool("dry-run", true, "")
+	set.Bool("create-namespace", true, "")
 	c = cli.NewContext(nil, set, nil)
 
 	testRunner = new(MockedRunner)
@@ -489,6 +492,21 @@ func TestSetNamespace(t *testing.T) {
 	err = setNamespace(c, "test-project", testRunner)
 	testRunner.AssertExpectations(t)
 	assert.NoError(t, err)
+
+	// Opt-out of auto namespace creation
+	set = flag.NewFlagSet("no-create-namespace-set", 0)
+	set.String("zone", "us-east1-b", "")
+	set.String("cluster", "cluster-0", "")
+	set.String("namespace", "Feature/1892-TEST-NS", "")
+	set.Bool("dry-run", false, "")
+	set.Bool("create-namespace", false, "")
+	c = cli.NewContext(nil, set, nil)
+
+	testRunner = new(MockedRunner)
+	testRunner.On("Run", []string{"kubectl", "config", "set-context", "gke_test-project_us-east1-b_cluster-0", "--namespace", "feature-1892-test-ns"}).Return(nil)
+	err = setNamespace(c, "test-project", testRunner)
+	testRunner.AssertExpectations(t)
+	assert.NoError(t, err)
 }
 
 func TestApplyManifests(t *testing.T) {