firebase-storage-ref.html

<!--
@license
Copyright 2016 Google Inc. All Rights Reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file or at
https://github.com/firebase/polymerfire/blob/master/LICENSE
-->

<link rel="import" href="../polymer/polymer.html">
<link rel="import" href="firebase-storage-behavior.html">
<script>
  (function(){
    'use strict';

    /**
    * The firebase-storage-ref element is an easy way to interact with a firebase
    * storage as an object and expose it to the Polymer databinding system.
    *
    * For example:
    *
    *     <firebase-storage-ref
    *       path="{{path}}"
    *       metadata="{{metadata}}"
    *       storage-uri="{{gsUri}}"
    *       download-url="{{downloadUrl}}">
    *     </firebase-storage-ref>
    *
    * This fetches file associated within the `path` attribute from the firebase storage
    * and produces the metadata and the download url associated with it.
    * It also exposes several firebase storage methods to manipulate and get
    * additional data from it.
    *
    * `<firebase-storage>` needs some information about how to talk to Firebase.
    * Set this configuration by adding a `<firebase-app>` element anywhere in your
    * app.
    */
    Polymer({
      is: 'firebase-storage-ref',

      properties: {
        /**
          * The url of the file for download
          */
        downloadUrl: {
          type: String,
          notify: true
        },

        /**
          * The metadata of the file
          */
        metadata: {
          type: Object,
          notify: true
        },

        /**
         * The Cloud Storage URI string of this object in the form `gs://<bucket>/<path>/<to>/<object>`
         */
        storageUri: {
          type: String,
          notify: true
        },

        /**
          * The upload task of the file when you use the put method.
          */
        uploadTask: {
          type: Object,
          notify: true
        }
      },

      behaviors: [
        Polymer.FirebaseStorageBehavior
      ],
      
      
      observers: [
        '__pathChanged(path, storage)'
      ],

      /**
      * @override
      */
      get isNew() {
        return !this.path;
      },

      /**
      * @override
      */
      get zeroValue() {
        return [];
      },
      
      __pathChanged: function(path) {
        if (this.storage) {
          this.getDownloadURL(path).then(function(downloadUrl) {
            this.downloadUrl = downloadUrl;
          }.bind(this)).catch(function(error) {
            this.fire('error', error, { bubble: false});
          }.bind(this));

          this.getMetadata(path).then(function(metadata) {
            this.metadata = metadata;
          }.bind(this)).catch(function(error) {
            this.fire('error', error, { bubble: false});
          }.bind(this));
          
          this.storageUri = this.toGsString(path);
        }
      },


      /**
      *  Resets this element's path
      */
      reset: function() {
        this.path = null;
        return Promise.resolve();
      },

      /**
      *  Sets the path from url
      */
      setPathFromUrl: function(url) {
        if (url) {
          this.path = this.getPathFromUrl(url);
          return new Promise.resolve();
        }
        return new Promise.resolve();
      },

      /**
      *  Get's the path from url
      */
      getPathFromUrl: function(url) {
        return url ? this.storage.refFromURL(url) : null;
      },

      /**
      *  Deletes the file associated in the firebase storage path
      */
      delete: function() {
        return this.__put().then(function() {
          return this.reset();
        }.bind(this));
      },

      /**
      *  Stores a new single file inside this path
      */
      put: function(file, metadata) {
        this.uploadTask = this.__put(null, file, metadata);
        return this.uploadTask;
      },

      /**
      *  Stores a string in a given format
      */
      putString: function(data, format, metadata) {
        this.uploadTask = this.__putString(null, data, format, metadata);
        return this.uploadTask;
      },

      /**
      *  Get the download url of the file
      */
      getDownloadURL: function(path) {
        if (path) {
          return this.storage.ref(path).getDownloadURL();
        } else if (this.ref) {
          return this.ref.getDownloadURL();
        }
        return new Promise(function(resolve, reject) {resolve();});
      },

      /**
      *  Get the metadata of the file
      */
      getMetadata: function(path) {
        if (path) {
          return this.storage.ref(path).getMetadata();
        } else if (this.ref) {
          return this.ref.getMetadata();
        }
        return new Promise(function(resolve, reject) {resolve();});
      },

      /**
       * Returns a gs:// URL for this object in the form gs://<bucket>/<path>/<to>/<object>
       */

      toGsString: function(path) {
        if (path) {
          return this.storage.ref(path).toString();
        } else if (this.ref) {
          return this.ref.toString();
        }
      },

      /**
      *  Sets the metadata of the file
      */
      setMetadata: function(metadata, path) {
        if (path) {
          return this.storage.ref(path).updateMetadata(metadata);
        } else if (this.ref) {
          return this.ref.updateMetadata(metadata);
        }
        return new Promise(function(resolve, reject) {resolve();});
      }
    });
  })()

</script>