expose metaInfo properties to render context

index.js

@@ -16,7 +16,47 @@
     // set installation inspection flag
     VueMeta.install.installed = true
 
-    // TODO: implement plugin
+    /**
+     * Does the grunt work of exposing component meta options
+     * to the server-rendered context
+     * @return {Object} - all the meta info for currently matched components
+     */
+    Vue.prototype.$meta = function $meta () {
+      return getMetaInfoDefinition(Vue, this)
+    }
+  }
+
+  /**
+   * Recursively traverses each component, checking for a `metaInfo`
+   * option. It then merges all these options into one object, giving
+   * higher priority to deeply nested components.
+   * @param  {Function} Vue - the Vue constructor
+   * @param  {Object} $instance - the current instance
+   * @param  {Object} [metaInfo={}] - the merged options
+   * @return {Object} metaInfo - the merged options
+   */
+  function getMetaInfoDefinition (Vue, $instance, metaInfo) {
+    // set default for first run
+    metaInfo = metaInfo || {}
+
+    // if current instance has a metaInfo option, merge it in
+    if ($instance.$options.metaInfo) {
+      metaInfo = Vue.util.mergeOptions(metaInfo, $instance.$options.metaInfo)
+    }
+
+    // check if any children also have a metaInfo option
+    // NOTE: since the order of $instance.$children cannot be gauranteed,
+    //       you should be careful about non-unique meta properties in
+    //       sibling components
+    var len = $instance.$children.length
+    if (len) {
+      var i = 0
+      for (; i < len; i++) {
+        metaInfo = getMetaInfoDefinition(Vue, $instance.$children[i], metaInfo)
+      }
+    }
+
+    return metaInfo
   }
 
   // automatic installation when global context