Support custom resources (hashicorp#215)

Notes:
 - Created an ExtendedClientset allowing generic access to K8S REST client
 - Refactored all usage of the provider to the K8S interfaces
 - Added a dependency on "github.com/ghodss/yaml"
 - Handle create, update, delete for custom resources
 - Custom resource update state delta between K8S, TF, and Desired is handled through transient fields

kubernetes/custom_resource_client.go

@@ -0,0 +1,239 @@
+package kubernetes
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"strings"
+
+	"github.com/ghodss/yaml"
+	flat "github.com/hashicorp/terraform/flatmap"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	runtime "k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	serializer "k8s.io/apimachinery/pkg/runtime/serializer"
+	pkgApi "k8s.io/apimachinery/pkg/types"
+	"k8s.io/client-go/kubernetes/scheme"
+	rest "k8s.io/client-go/rest"
+)
+
+type GenericKubernetesObject struct {
+	*runtime.Unknown
+	RawJSON    map[string]interface{}
+	ObjectMeta *metav1.ObjectMeta
+	GenericID  *GenericObjectID
+}
+
+func (obj *GenericKubernetesObject) FlattenedSpec() map[string]string {
+	processedSpec := obj.RawJSON["spec"].(map[string]interface{})
+	return flat.Flatten(processedSpec)
+}
+
+func (obj *GenericKubernetesObject) YamlSpec() string {
+	processedSpec := obj.RawJSON["spec"].(map[string]interface{})
+	bytes, _ := yaml.Marshal(processedSpec)
+	return string(bytes)
+}
+
+func (obj *GenericKubernetesObject) ID() string {
+	return obj.GenericID.ID()
+}
+
+type GenericObjectID struct {
+	Group     string
+	Version   string
+	Kind      string
+	Namespace string
+	Name      string
+}
+
+func genericObjectID(id, kind string) *GenericObjectID {
+	if strings.TrimSpace(id) == "" {
+		return nil
+	}
+
+	parts := strings.SplitN(strings.TrimSpace(id), "/", 4)
+
+	genericID := &GenericObjectID{
+		Group:   parts[0],
+		Version: parts[1],
+		Kind:    kind,
+	}
+
+	if len(parts) == 3 {
+		genericID.Name = parts[2]
+	} else if len(parts) == 4 {
+		genericID.Namespace = parts[2]
+		genericID.Name = parts[3]
+	}
+
+	return genericID
+}
+
+func (id *GenericObjectID) ApiVersion() string {
+	return fmt.Sprintf("%s/%s", id.Group, id.Version)
+}
+
+func (id *GenericObjectID) Resource() string {
+	return fmt.Sprintf("%ss", strings.ToLower(id.Kind))
+}
+
+func (id *GenericObjectID) ID() string {
+	idString := make([]string, 1)
+	idString[0] = id.ApiVersion()
+	if id.Namespace != "" {
+		idString = append(idString, id.Namespace)
+	}
+
+	return strings.Join(append(idString, id.Name), "/")
+}
+
+type CustomResourceClient struct {
+	config *rest.Config
+}
+
+// NewForConfig creates a new AdmissionregistrationV1alpha1Client for the given config.
+func NewCustomResourceClient(c *rest.Config) (*CustomResourceClient, error) {
+	configShallowCopy := *c
+	return &CustomResourceClient{&configShallowCopy}, nil
+}
+
+func (c *CustomResourceClient) setConfigDefaults(target *GenericObjectID) rest.Config {
+	configShallowCopy := *c.config
+	configShallowCopy.GroupVersion = &schema.GroupVersion{Group: target.Group, Version: target.Version}
+	configShallowCopy.APIPath = "/apis"
+	configShallowCopy.ContentType = runtime.ContentTypeJSON
+	configShallowCopy.NegotiatedSerializer = serializer.DirectCodecFactory{CodecFactory: scheme.Codecs}
+	return configShallowCopy
+}
+
+func (c *CustomResourceClient) client(target *GenericObjectID) (rest.Interface, error) {
+	config := c.setConfigDefaults(target)
+	client, err := rest.RESTClientFor(&config)
+	if err != nil {
+		return nil, err
+	}
+	return client, nil
+}
+
+func (result *GenericKubernetesObject) process() error {
+	rawJSON := map[string]interface{}{}
+	err := json.Unmarshal(result.Raw, &rawJSON)
+	if err != nil {
+		return err
+	}
+	result.RawJSON = rawJSON
+
+	metadata, err := json.Marshal(result.RawJSON["metadata"])
+	if err != nil {
+		return err
+	}
+
+	objectMeta := metav1.ObjectMeta{}
+	err = json.Unmarshal(metadata, &objectMeta)
+	if err != nil {
+		return err
+	}
+
+	result.ObjectMeta = &objectMeta
+	result.GenericID = genericObjectID(result.RawJSON["apiVersion"].(string), result.RawJSON["kind"].(string))
+	result.GenericID.Name = objectMeta.Name
+	result.GenericID.Namespace = objectMeta.Namespace
+
+	return nil
+}
+
+func (c *CustomResourceClient) request(target *GenericObjectID, request *rest.Request) *rest.Request {
+	if target.Namespace != "" {
+		return request.Resource(target.Resource()).Namespace(target.Namespace)
+	}
+	return request.Resource(target.Resource())
+}
+
+func (c *CustomResourceClient) Get(target *GenericObjectID) (result *GenericKubernetesObject, err error) {
+	client, err := c.client(target)
+	if err != nil {
+		return nil, err
+	}
+
+	rawResult := runtime.Unknown{}
+	err = c.request(target, client.Get()).
+		Name(target.Name).
+		Do().
+		Into(&rawResult)
+
+	if err != nil {
+		return
+	}
+
+	result = &GenericKubernetesObject{Unknown: &rawResult}
+	result.process()
+	return
+}
+
+func (c *CustomResourceClient) Delete(target *GenericObjectID) (err error) {
+	client, err := c.client(target)
+	if err != nil {
+		return err
+	}
+
+	return c.request(target, client.Delete()).
+		Name(target.Name).
+		Do().
+		Error()
+}
+
+func (c *CustomResourceClient) Create(target *GenericObjectID, obj map[string]interface{}) (result *GenericKubernetesObject, err error) {
+	client, err := c.client(target)
+	if err != nil {
+		return nil, err
+	}
+
+	raw, err := json.Marshal(obj)
+	if err != nil {
+		return nil, err
+	}
+
+	rawResult := runtime.Unknown{}
+	err = c.request(target, client.Post()).
+		Body(raw).
+		Do().
+		Into(&rawResult)
+
+	if err != nil {
+		return
+	}
+
+	result = &GenericKubernetesObject{Unknown: &rawResult}
+	result.process()
+	return
+}
+
+func (c *CustomResourceClient) Update(target *GenericObjectID, ops PatchOperations) (result *GenericKubernetesObject, err error) {
+	client, err := c.client(target)
+	if err != nil {
+		return nil, err
+	}
+
+	data, err := ops.MarshalJSON()
+	if err != nil {
+		return nil, fmt.Errorf("Failed to marshal update operations: %s", err)
+	}
+
+	log.Printf("[INFO] Updating custom %s: %s", target.ID(), string(data))
+
+	rawResult := runtime.Unknown{}
+	err = c.request(target, client.Patch(pkgApi.JSONPatchType)).
+		Name(target.Name).
+		Body(data).
+		Do().
+		Into(&rawResult)
+
+	if err != nil {
+		return
+	}
+
+	result = &GenericKubernetesObject{Unknown: &rawResult}
+	result.process()
+	return
+}

kubernetes/event_helpers.go

@@ -11,7 +11,7 @@ import (
 	kubernetes "k8s.io/client-go/kubernetes"
 )
 
-func getLastWarningsForObject(conn *kubernetes.Clientset, metadata meta_v1.ObjectMeta, kind string, limit int) ([]api.Event, error) {
+func getLastWarningsForObject(conn kubernetes.Interface, metadata meta_v1.ObjectMeta, kind string, limit int) ([]api.Event, error) {
 	m := map[string]string{
 		"involvedObject.name": metadata.Name,
 		"involvedObject.kind": kind,

kubernetes/provider.go

@@ -16,6 +16,16 @@ import (
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 )
 
+type ExtendedClientset struct {
+	*kubernetes.Clientset
+	customResource *CustomResourceClient
+}
+
+// la la connect the dots
+func (c *ExtendedClientset) CustomResource() *CustomResourceClient {
+	return c.customResource
+}
+
 func Provider() terraform.ResourceProvider {
 	return &schema.Provider{
 		Schema: map[string]*schema.Schema{
@@ -115,6 +125,7 @@ func Provider() terraform.ResourceProvider {
 			"kubernetes_config_map":                resourceKubernetesConfigMap(),
 			"kubernetes_daemonset":                 resourceKubernetesDaemonSet(),
 			"kubernetes_deployment":                resourceKubernetesDeployment(),
+			"kubernetes_generic":                   resourceKubernetesCustom(),
 			"kubernetes_horizontal_pod_autoscaler": resourceKubernetesHorizontalPodAutoscaler(),
 			"kubernetes_limit_range":               resourceKubernetesLimitRange(),
 			"kubernetes_namespace":                 resourceKubernetesNamespace(),
@@ -185,7 +196,12 @@ func providerConfigure(d *schema.ResourceData) (interface{}, error) {
 		return nil, fmt.Errorf("Failed to configure: %s", err)
 	}
 
-	return k, nil
+	rest, err := NewCustomResourceClient(cfg)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to configure: %s", err)
+	}
+
+	return ExtendedClientset{Clientset: k, customResource: rest}, nil
 }
 
 func tryLoadingConfigFile(d *schema.ResourceData) (*restclient.Config, error) {