From acbc25ce998dbae3d4ddb71d1120bc270f76147c Mon Sep 17 00:00:00 2001
From: Michael Krotscheck <krotscheck@gmail.com>
Date: Tue, 30 Aug 2016 13:11:40 -0700
Subject: [PATCH] Created common service abstraction

This patch creates a common class named AbstractService from which
all API classes can inherit common logic.

Change-Id: I18339ac19ed2b97a7b9b3d6a0f1e01292080c422
---
 src/glance.js                |  7 ++++---
 src/keystone.js              |  7 ++++---
 src/util/abstract_service.js | 37 ++++++++++++++++++++++++++++++++++++
 3 files changed, 45 insertions(+), 6 deletions(-)
 create mode 100644 src/util/abstract_service.js

diff --git a/src/glance.js b/src/glance.js
index 1d42002..53c4300 100644
--- a/src/glance.js
+++ b/src/glance.js
@@ -13,7 +13,7 @@
  * the License for the specific language governing permissions and limitations
  * under the License.
  */
-import Http from './util/http';
+import AbstractService from './util/abstract_service';
 
 /**
  * A list of all supported versions. Please keep this array sorted by most recent.
@@ -25,7 +25,7 @@ const supportedGlanceVersions = [
   'v2.3'
 ];
 
-export default class Glance {
+export default class Glance extends AbstractService {
 
   /**
    * This class provides direct, idempotent, low-level access to the Glance API of a specific
@@ -43,6 +43,8 @@ export default class Glance {
    * @param {{}} endpointConfig The configuration element for a specific glance endpoint.
    */
   constructor (endpointConfig) {
+    super();
+
     // Sanity checks.
     if (!endpointConfig || !endpointConfig.url) {
       throw new Error('An endpoint configuration is required.');
@@ -50,7 +52,6 @@ export default class Glance {
     // Clone the config, so that this instance is immutable
     // at runtime (no modifying the config after the fact).
     this._config = Object.assign({}, endpointConfig);
-    this.http = new Http();
   }
 
   /**
diff --git a/src/keystone.js b/src/keystone.js
index f5ec530..fd774c3 100644
--- a/src/keystone.js
+++ b/src/keystone.js
@@ -1,4 +1,4 @@
-import Http from './util/http';
+import AbstractService from './util/abstract_service';
 
 /**
  * A list of all supported versions. Please keep this array sorted by most recent.
@@ -10,7 +10,7 @@ const supportedKeystoneVersions = [
   'v3.7'
 ];
 
-export default class Keystone {
+export default class Keystone extends AbstractService {
 
   /**
    * This class provides direct, idempotent, low-level access to the Keystone API of a specific
@@ -23,6 +23,8 @@ export default class Keystone {
    * @see http://docs.openstack.org/developer/os-client-config/#site-specific-file-locations
    */
   constructor (cloudConfig) {
+    super();
+
     // Sanity checks.
     if (!cloudConfig) {
       throw new Error('A configuration is required.');
@@ -30,7 +32,6 @@ export default class Keystone {
     // Clone the config, so that this instance is immutable
     // at runtime (no modifying the config after the fact).
     this.cloudConfig = Object.assign({}, cloudConfig);
-    this.http = new Http();
   }
 
   /**
diff --git a/src/util/abstract_service.js b/src/util/abstract_service.js
new file mode 100644
index 0000000..11ba0d3
--- /dev/null
+++ b/src/util/abstract_service.js
@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2016 Hewlett Packard Enterprise Development L.P.
+ *
+ * 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.
+ */
+
+import Http from './http';
+
+/**
+ * An abstract implementation of our services, which includes logic common to all of our services.
+ *
+ * @author Michael Krotscheck
+ */
+export default class AbstractService {
+
+  /**
+   * Our HTTP service instance.
+   *
+   * @returns {Http} Our HTTP service instance.
+   */
+  get http () {
+    if (!this._http) {
+      this._http = new Http();
+    }
+    return this._http;
+  }
+}