Implements replace strategy (#116)

* Implement strategy.spinnaker.io/replace

* Adds tests for Replace

* Fixes linter issue

* Implements strategy.spinnaker.io/replace

internal/api/core/kubernetes/deploy.go

@@ -148,13 +148,25 @@ func (cc *Controller) Deploy(c *gin.Context, dm DeployManifestRequest) {
 			}
 		}
 
-		meta, err := provider.Client.Apply(&manifest)
-		if err != nil {
-			e := fmt.Errorf("error applying manifest (kind: %s, apiVersion: %s, name: %s): %s",
-				manifest.GetKind(), manifest.GroupVersionKind().Version, manifest.GetName(), err.Error())
-			clouddriver.Error(c, http.StatusInternalServerError, e)
+		meta := kubernetes.Metadata{}
+		if kubernetes.Replace(manifest) {
+			meta, err = provider.Client.Replace(&manifest)
+			if err != nil {
+				e := fmt.Errorf("error replacing manifest (kind: %s, apiVersion: %s, name: %s): %s",
+					manifest.GetKind(), manifest.GroupVersionKind().Version, manifest.GetName(), err.Error())
+				clouddriver.Error(c, http.StatusInternalServerError, e)
 
-			return
+				return
+			}
+		} else {
+			meta, err = provider.Client.Apply(&manifest)
+			if err != nil {
+				e := fmt.Errorf("error applying manifest (kind: %s, apiVersion: %s, name: %s): %s",
+					manifest.GetKind(), manifest.GroupVersionKind().Version, manifest.GetName(), err.Error())
+				clouddriver.Error(c, http.StatusInternalServerError, e)
+
+				return
+			}
 		}
 
 		kr := kubernetes.Resource{

internal/api/core/kubernetes/deploy_test.go

@@ -314,6 +314,42 @@ var _ = Describe("Deploy", func() {
 		})
 	})
 
+	When("the manifest uses replace strategy", func() {
+		BeforeEach(func() {
+			deployManifestRequest = DeployManifestRequest{
+				Manifests: []map[string]interface{}{
+					{
+						"kind":       "Job",
+						"apiVersion": "v1",
+						"metadata": map[string]interface{}{
+							"annotations": map[string]interface{}{
+								"strategy.spinnaker.io/replace": "true",
+							},
+							"name":      "test-name",
+							"namespace": "test-namespace",
+						},
+					},
+				},
+			}
+		})
+
+		When("replace returns an error", func() {
+			BeforeEach(func() {
+				fakeKubeClient.ReplaceReturns(kubernetes.Metadata{}, errors.New("ReplaceReturns fake error"))
+			})
+
+			It("returns an error", func() {
+				Expect(c.Writer.Status()).To(Equal(http.StatusInternalServerError))
+				Expect(c.Errors.Last().Error()).To(Equal("error replacing manifest (kind: Job, apiVersion: v1, name: test-name): ReplaceReturns fake error"))
+			})
+		})
+
+		It("it succeeds, calling replace", func() {
+			Expect(c.Writer.Status()).To(Equal(http.StatusOK))
+			Expect(fakeKubeClient.ReplaceCallCount()).To(Equal(1))
+		})
+	})
+
 	Context("when the manifest uses Spinnaker managed traffic", func() {
 		BeforeEach(func() {
 			deployManifestRequest = DeployManifestRequest{

internal/api/core/kubernetes/runjob.go

@@ -56,7 +56,13 @@ func (cc *Controller) RunJob(c *gin.Context, rj RunJobRequest) {
 
 	kubernetes.BindArtifacts(&u, append(rj.RequiredArtifacts, rj.OptionalArtifacts...))
 
-	meta, err := provider.Client.Apply(&u)
+	meta := kubernetes.Metadata{}
+	if kubernetes.Replace(u) {
+		meta, err = provider.Client.Replace(&u)
+	} else {
+		meta, err = provider.Client.Apply(&u)
+	}
+
 	if err != nil {
 		clouddriver.Error(c, http.StatusInternalServerError, err)
 		return

internal/api/core/kubernetes/runjob_test.go

@@ -113,6 +113,38 @@ var _ = Describe("RunJob", func() {
 		})
 	})
 
+	When("the manifest uses replace strategy", func() {
+		BeforeEach(func() {
+			runJobRequest.Manifest = map[string]interface{}{
+				"kind":       "Job",
+				"apiVersion": "v1",
+				"metadata": map[string]interface{}{
+					"annotations": map[string]interface{}{
+						"strategy.spinnaker.io/replace": "true",
+					},
+					"name":      "test-name",
+					"namespace": "test-namespace",
+				},
+			}
+		})
+
+		When("replace returns an error", func() {
+			BeforeEach(func() {
+				fakeKubeClient.ReplaceReturns(kubernetes.Metadata{}, errors.New("ReplaceReturns fake error"))
+			})
+
+			It("returns an error", func() {
+				Expect(c.Writer.Status()).To(Equal(http.StatusInternalServerError))
+				Expect(c.Errors.Last().Error()).To(Equal("ReplaceReturns fake error"))
+			})
+		})
+
+		It("it succeeds, calling replace", func() {
+			Expect(c.Writer.Status()).To(Equal(http.StatusOK))
+			Expect(fakeKubeClient.ReplaceCallCount()).To(Equal(1))
+		})
+	})
+
 	Context("annotating 'artifact.spinnaker.io/location'", func() {
 		When("the namespace is not set", func() {
 			BeforeEach(func() {

internal/kubernetes/client.go

@@ -35,6 +35,7 @@ type Metadata struct {
 //go:generate counterfeiter . Client
 type Client interface {
 	Apply(*unstructured.Unstructured) (Metadata, error)
+	Replace(*unstructured.Unstructured) (Metadata, error)
 	DeleteResourceByKindAndNameAndNamespace(string, string, string, metav1.DeleteOptions) error
 	Discover() error
 	GVRForKind(string) (schema.GroupVersionResource, error)
@@ -136,6 +137,81 @@ func (c *client) Apply(u *unstructured.Unstructured) (Metadata, error) {
 	return metadata, nil
 }
 
+// Replace a given manifest.
+func (c *client) Replace(u *unstructured.Unstructured) (Metadata, error) {
+	metadata := Metadata{}
+	gvk := u.GroupVersionKind()
+
+	restMapping, err := c.mapper.RESTMapping(gvk.GroupKind(), gvk.Version)
+	if err != nil {
+		return metadata, err
+	}
+
+	gvr := restMapping.Resource
+	gv := gvk.GroupVersion()
+	c.config.GroupVersion = &gv
+
+	restClient, err := newRestClient(*c.config, gv)
+	if err != nil {
+		return metadata, err
+	}
+
+	helper := resource.NewHelper(restClient, restMapping)
+
+	info := &resource.Info{
+		Client:          restClient,
+		Mapping:         restMapping,
+		Namespace:       u.GetNamespace(),
+		Name:            u.GetName(),
+		Source:          "",
+		Object:          u,
+		ResourceVersion: restMapping.Resource.Version,
+	}
+
+	// If annotation kubectl.kubernetes.io/last-applied-configuration exists, then update it.
+	err = util.CreateOrUpdateAnnotation(false, info.Object, unstructured.UnstructuredJSONScheme)
+	if err != nil {
+		return metadata, err
+	}
+
+	exists := true
+	// Determine if the resource currently exists.
+	if err := info.Get(); err != nil {
+		if !errors.IsNotFound(err) {
+			return metadata, err
+		}
+
+		exists = false
+	}
+
+	if !exists {
+		// Create the resource if it doesn't exist.
+		obj, err := helper.Create(info.Namespace, true, info.Object)
+		if err != nil {
+			return metadata, err
+		}
+
+		_ = info.Refresh(obj, true)
+	} else {
+		// Replace the resource if it does exist.
+		obj, err := helper.Replace(info.Namespace, info.Name, true, info.Object)
+		if err != nil {
+			return metadata, err
+		}
+
+		_ = info.Refresh(obj, true)
+	}
+
+	metadata.Name = u.GetName()
+	metadata.Namespace = u.GetNamespace()
+	metadata.Group = gvr.Group
+	metadata.Resource = gvr.Resource
+	metadata.Kind = gvk.Kind
+	metadata.Version = gvr.Version
+
+	return metadata, nil
+}
+
 func newRestClient(restConfig rest.Config, gv schema.GroupVersion) (rest.Interface, error) {
 	restConfig.ContentConfig = resource.UnstructuredPlusDefaultContentConfig()
 	restConfig.GroupVersion = &gv