Abstracting Facebook API functions

Model/StreamPost.php

@@ -0,0 +1,122 @@
+<?php
+
+/*
+ * This file is part of the FOSFacebookBundle package.
+ *
+ * (c) FriendsOfSymfony <http://friendsofsymfony.github.com/>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace FOS\FacebookBundle\Model;
+
+use \InvalidArgumentException;
+
+/**
+ *
+ * This class functions as a model for messages to be sent by the facebookPush-service to the Facebook api.
+ * @author Teemu Reisbacka <[email protected]>
+ *
+ */
+class StreamPost
+{
+    protected $accessToken;
+    protected $message;
+    protected $attachment;
+    protected $linkout;
+
+    /**
+     * Sets the access token used in message body. This is set automatically inside facebookPush-service.
+     *
+     * @param string $accessToken
+     */
+    public function setAccessToken($accessToken)
+    {
+        $this->accessToken = $accessToken;
+    }
+
+    /**
+     * Sets the actual text content of the message
+     *
+     * @param string $message
+     */
+    public function setMessage($message)
+    {
+        $this->message = $message;
+    }
+
+    /**
+     * Adds an attachment-picture to your Facebook message. If you specify a link, the image will function as a link.
+     * If you set an attachment, you cannot set any additional links with setLink(...).
+     *
+     * @param string $name	This is the title of the attachment (top-most descriptive text)
+     * @param string $caption	This is the image caption (text under the title)
+     * @param string $uriAttachment	Full uri to the image you wish to attach. This location must be visible to Facebook, they will cache the picture.
+     * @param string $uriLinkOut	Full uri to where you sish the image to link to
+     * @param string $description	Description field in the message. If you do not specify this, Facebook may crawl the website specified in the link/image and attach a meta-description foiund from there to the message.
+     */
+    public function setAttachment($name, $caption, $uriAttachment, $uriLinkOut = null, $description = null)
+    {
+        $attachment = array(
+            'name' => $name,
+            'caption' => $caption,
+            'picture' =>  $uriAttachment,
+        );
+
+        if (!empty($description)) {
+            $attachment['description'] = $description;
+        }
+        if (!empty($uriLinkOut)) {
+            $attachment['link'] = $uriLinkOut;
+        }
+        $this->attachment = $attachment;
+    }
+
+    /**
+     * Shortcut for adding a link to you Facebook-message without an image. If you
+     * specify an attachment with setAttachment(...), that will be used instead of this link.
+     *
+     * @param string $name This is the title of the link (top-most descriptive text)
+     * @param string $linkOut Full uri to where you wish to link to
+     * @param string $caption Optional description of the link
+     */
+    public function setLink($name, $linkOut, $caption = null)
+    {
+        $this->linkout = array(
+            'name' => $name,
+            'link' => $linkOut
+        );
+        if (!empty($caption)) {
+            $this->linkout['caption'] = $caption;
+        }
+     }
+
+    /**
+     * Formats this object into on array that can be fed to the php-api class. This function will be called automatically.
+     *
+     * @throws \InvalidArgumentException;
+     * @return array
+     */
+    public function formatData()
+    {
+        if (empty($this->accessToken)) {
+            throw new \InvalidArgumentException('cannot format Facebook message: Facebook access token is empty');
+        }
+        if (empty($this->message)) {
+            throw new \InvalidArgumentException('cannot format Facebook message: Message is empty, nothing to send');
+        }
+        $streamPost = array(
+            'access_token' => $this->accessToken,
+            'message' => $this->message
+        );
+        if (!empty($this->linkout)) {
+            $streamPost = array_merge($streamPost, $this->linkout);
+        }
+        if (!empty($this->attachment)) {
+            $streamPost = array_merge($streamPost, $this->attachment);
+        }
+
+        return $streamPost;
+    }
+}

Resources/config/facebook.xml

@@ -31,5 +31,9 @@
             <tag name="twig.extension" />
         </service>
 
+        <service id="fos_facebook.facebook_push" class="FOS\FacebookBundle\Services\FacebookPush">
+            <argument type="service" id="fos_facebook.api" />
+        </service>
+
     </services>
 </container>

Services/FacebookPush.php

@@ -0,0 +1,171 @@
+<?php
+
+/*
+ * This file is part of the FOSFacebookBundle package.
+ *
+ * (c) FriendsOfSymfony <http://friendsofsymfony.github.com/>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace FOS\FacebookBundle\Services;
+
+use Symfony\Bundle\FrameworkBundle\Controller\Controller;
+use FOS\FacebookBundle\Model\StreamPost as BaseMessage;
+use \BaseFacebook;
+use \FacebookApiException;
+use \InvalidArgumentException;
+use \UnexpectedValueException;
+
+/**
+ *
+ * This class provides a service that abstracts Facebook API functionality such as retrieving user information and
+ * posting data to Facebook API.
+ * @author Teemu Reisbacka <[email protected]>
+ *
+ */
+class FacebookPush
+{
+    protected $facebook;
+    protected $errorMessage;
+
+    public function __construct(BaseFacebook $facebook)
+    {
+        $this->facebook = $facebook;
+    }
+
+    /**
+     * Returns error message if an executed function returned a failure (false value).
+     *
+     * @return string
+     */
+    public function getErrorMessage()
+    {
+
+        return empty($this->errorMessage) ? '' : $this->errorMessage;
+    }
+
+    /**
+     * Retrieves available user information from Facebook for the logged in user. Available information
+     * depends on what access privileges the user has granted to your app.
+     *
+     * @return array|null
+     */
+    public function getUserInfromation()
+    {
+        $accessToken = $this->facebook->getAccessToken();
+        /*	Adding the locale parameter is important, because otherwise Facebook api might localize some
+         * 	variable values, such as gender.
+         */
+        $me = json_decode(file_get_contents("https://graph.facebook.com/me?access_token={$accessToken}&locale=en_US"), true);
+
+        return $me;
+    }
+
+    /**
+     * Retrieves the profile picture of the logged in user in binary format, so that you can
+     * save it locally.
+     *
+     * @return string|boolean
+     */
+    public function getProfilePicture()
+    {
+        $facebookUID = $this->facebook->getUser();
+        if (empty($facebookUID)) {
+            return null;
+        }
+
+        $binaryImage = file_get_contents("http://graph.facebook.com/{$facebookUID}/picture?type=large");
+
+        return $binaryImage;
+    }
+
+    /**
+     * Publishes a message to user's Facebook stream as the user. You application name will be displayed at the bottom
+     * of the message.
+     * REQUIRES Facebook access permission "publish_stream"
+     *
+     * @param Rohea\FacebookBundle\Models\streamPost $streamPost Stream post object
+     * @param string $accessToken Optional Facebook Access token, if not given, logged in user is used
+     * @return boolean
+     */
+    public function publishStream(BaseMessage $streamPost, $accessToken = null)
+    {
+        if (empty($accessToken)) {
+            $accessToken = $this->facebook->getAccessToken();
+        }
+        if (empty($accessToken)) {
+            throw new InvalidArgumentException('No facebook access token, cannot post to stream');
+        }
+
+        $streamPost->setAccessToken($accessToken);
+        $message = $streamPost->formatData();
+        try {
+            $result = $this->facebook->api( '/me/feed/', 'post', $message );
+
+            /*	Confirm that the post went through -> Facebook api return message id
+             */
+            if (!is_array($result) || empty($result["id"])) {
+                $this->errorMessage = "Did not receive message id back from the api, post failed.";
+                return false;
+            }
+        } catch (FacebookApiException $e) {
+            $this->errorMessage = $e->getMessage();
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Publishes a message to user's Facebook page as the page.
+     * REQUIRES Facebook access permission "manage_pages"
+     *
+     * @param Rohea\FacebookBundle\Models\streamPost $streamPost Stream post object
+     * @param string $pageID Your page facebook id. You can see this for examnple in your browser uri-bar when browsing the page.
+     * @return boolean
+     */
+    public function publishPage(BaseMessage $streamPost, $pageID)
+    {
+        try {
+            $accessToken = $this->getPageAccessToken($pageID);
+            $streamPost->setAccessToken($accessToken);
+            $message = $streamPost->formatData();
+            $result = $this->facebook->api( "/{$pageID}/feed/", 'post', $message );
+
+            /*	Confirm that the post went through -> Facebook api return message id
+             */
+            if (!is_array($result) || empty($result["id"])) {
+                $this->errorMessage = "Did not receive message id back from the api, post failed.";
+                return false;
+            }
+        } catch (FacebookApiException $e) {
+            $this->errorMessage = $e->getMessage();
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Attempts to query access token for give Facebook page
+     * REQUIRES Facebook access permission "manage_pages"
+     *
+     * @param string $pageID Facebook page id
+     * @throws \UnexpectedValueException
+     * @return string
+     */
+    public function getPageAccessToken($pageID)
+    {
+        $pageInfo = $this->facebook->api("/$pageID?fields=access_token");
+
+        if (empty($pageInfo['access_token'])) {
+            throw new UnexpectedValueException("Could not retrieve access token for the page $pageID");
+        }
+
+        return $pageInfo['access_token'];
+    }
+}