Add most of components and prepare for V1 Release

src/manager.js

@@ -0,0 +1,73 @@
+let isApiSetUp = false
+
+/**
+ * @param apiKey    API Key, or object with the URL parameters. For example
+ *                  to use Google Maps Premium API, pass
+ *                    `{ client: <YOUR-CLIENT-ID> }`.
+ *                  You may pass the libraries and/or version (as `v`) parameter into
+ *                  this parameter and skip the next two parameters
+ * @param version   Google Maps version
+ * @param libraries Libraries to load (@see
+ *                  https://developers.google.com/maps/documentation/javascript/libraries)
+ * @param loadCn    Boolean. If set to true, the map will be loaded from google maps China
+ *                  (@see https://developers.google.com/maps/documentation/javascript/basics#GoogleMapsChina)
+ *
+ * Example:
+ * ```
+ *      import {load} from 'vue-google-maps'
+ *
+ *      load(<YOUR-API-KEY>)
+ *
+ *      load({
+ *              key: <YOUR-API-KEY>,
+ *      })
+ *
+ *      load({
+ *              client: <YOUR-CLIENT-ID>,
+ *              channel: <YOUR CHANNEL>
+ *      })
+ * ```
+ */
+export const loadGmapApi = (options, loadCn) => {
+  if (typeof document === 'undefined') {
+    // Do nothing if run from server-side
+    return
+  }
+  if (!isApiSetUp) {
+    isApiSetUp = true
+
+    const googleMapScript = document.createElement('SCRIPT')
+
+    // Allow options to be an object.
+    // This is to support more esoteric means of loading Google Maps,
+    // such as Google for business
+    // https://developers.google.com/maps/documentation/javascript/get-api-key#premium-auth
+    if (typeof options !== 'object') {
+      throw new Error('options should  be an object')
+    }
+
+    // libraries
+    if (Array.prototype.isPrototypeOf(options.libraries)) {
+      options.libraries = options.libraries.join(',')
+    }
+    options['callback'] = 'vueGoogleMapsInit'
+
+    let baseUrl = 'https://maps.googleapis.com/'
+
+    if (typeof loadCn === 'boolean' && loadCn === true) {
+      baseUrl = 'https://maps.google.cn/'
+    }
+
+    let url = baseUrl + 'maps/api/js?' +
+      Object.keys(options)
+        .map((key) => encodeURIComponent(key) + '=' + encodeURIComponent(options[key]))
+        .join('&')
+
+    googleMapScript.setAttribute('src', url)
+    googleMapScript.setAttribute('async', '')
+    googleMapScript.setAttribute('defer', '')
+    document.head.appendChild(googleMapScript)
+  } else {
+    throw new Error('You already started the loading of google maps')
+  }
+}