Merge "Plugin code refactoring"

1 files changed, 92 insertions, 0 deletions

diff --git a/src/k8splugin/internal/plugin/helpers.go b/src/k8splugin/internal/plugin/helpers.go
new file mode 100644
index 00000000..efcd18c1
--- /dev/null
+++ b/src/k8splugin/internal/plugin/helpers.go
@@ -0,0 +1,92 @@
+/*
+ * Copyright 2019 Intel Corporation, Inc
+ *
+ * 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 plugin
+
+import (
+	"log"
+	"strings"
+
+	utils "k8splugin/internal"
+	"k8splugin/internal/helm"
+
+	pkgerrors "github.com/pkg/errors"
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/kubernetes"
+)
+
+// KubernetesConnector is an interface that is expected to be implemented
+// by any code that calls the plugin framework functions.
+// It implements methods that are needed by the plugins to get Kubernetes
+// clients and other information needed to interface with Kubernetes
+type KubernetesConnector interface {
+	//GetMapper returns the RESTMapper that was created for this client
+	GetMapper() meta.RESTMapper
+
+	//GetDynamicClient returns the dynamic client that is needed for
+	//unstructured REST calls to the apiserver
+	GetDynamicClient() dynamic.Interface
+
+	// GetStandardClient returns the standard client that can be used to handle
+	// standard kubernetes kinds
+	GetStandardClient() kubernetes.Interface
+}
+
+// Reference is the interface that is implemented
+type Reference interface {
+	//Create a kubernetes resource described by the yaml in yamlFilePath
+	Create(yamlFilePath string, namespace string, client KubernetesConnector) (string, error)
+
+	//Get a kubernetes resource based on the groupVersionKind and resourceName provided in resource
+	Get(resource helm.KubernetesResource, namespace string, client KubernetesConnector) (string, error)
+
+	//List all resources of the specified GroupVersionKind in the given namespace
+	//If gvk is empty, the plugin will return all supported objects in the namespace
+	List(gvk schema.GroupVersionKind, namespace string, client KubernetesConnector) ([]helm.KubernetesResource, error)
+
+	//Delete a kubernetes resource described in the provided namespace
+	Delete(resource helm.KubernetesResource, namespace string, client KubernetesConnector) error
+}
+
+// GetPluginByKind returns a plugin by the kind name
+// If plugin does not exist, it will return the generic plugin
+// TODO: Change this once we have a plugin registration mechanism
+func GetPluginByKind(kind string) (Reference, error) {
+
+	typePlugin, ok := utils.LoadedPlugins[strings.ToLower(kind)]
+	if !ok {
+		log.Println("No plugin for kind " + kind + " found. Using generic Plugin")
+		typePlugin, ok = utils.LoadedPlugins["generic"]
+		if !ok {
+			return nil, pkgerrors.New("No generic plugin found")
+		}
+	}
+
+	symbol, err := typePlugin.Lookup("ExportedVariable")
+	if err != nil {
+		return nil, pkgerrors.Wrap(err, "No ExportedVariable symbol found")
+	}
+
+	//Assert if it implements the PluginReference interface
+	pluginImpl, ok := symbol.(Reference)
+	if !ok {
+		return nil, pkgerrors.New("ExportedVariable does not implement plugins.Reference interface type")
+	}
+
+	return pluginImpl, nil
+}