Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/joshuaestes/sffeed2plugin

git mirror
https://github.com/joshuaestes/sffeed2plugin

Last synced: 1 day ago
JSON representation

git mirror

Awesome Lists containing this project

README 

        
= sfFeed2 plugin =



The `sfFeed2Plugin` offers an object interface for feeds and feed items, feed input methods using a web feed or an array of objects as source, and feed output methods for displaying items on a page and serving feeds through a symfony application.



== Possible uses ==



 * serving a RSS/Atom feed based on model objects

 * Using web feeds as data source

 * Feed aggregator



As compared with the `sfFeedPlugin`, this plugin has a cleaner code separation in classes and offers more features. The syntax differs, but many classes have the same names, therefore the two plugins are not compatible.



== Contents ==



This plugin contains four data structure classes:



 * `sfFeed`

 * `sfFeedItem`

 * `sfFeedImage`

 * `sfFeedEnclosure`



It also contains specific classes containing specific input/output methods based on specific feed formats:



 * `sfAtom1Feed`

 * `sfRssFeed`

 * `sfRss10Feed`

 * `sfRss201Feed`

 * `sfRss091Feed`



Last but not least, the most important (and smart) class is the feed manager, which contains only static methods:



 * `sfFeedPeer`



Unit tests are available in the SVN repository.



== Installation ==



Installation of the plugin differs on the version of symfony you are using.



  * Install the plugin (symfony 1.0):

{{{

$ symfony plugin-install http://plugins.symfony-project.com/sfFeed2Plugin

}}}



  * Install the plugin (symfony 1.1+):

{{{

$ symfony plugin:install sfFeed2Plugin

}}}



  * Alternatively, if you don't have PEAR installed, you can download the latest package attached to this plugin's wiki page and extract it under your project's `plugins/` directory



  * Clear the cache to enable the autoloading to find the new class

{{{

$ symfony cc

}}}



== Tutorials ==



=== Building a feed from an array of objects ===



==== Example data ====



Let's take an example of a simple blog application with a `Post` and an `Author` table:



||''Post''    || ''Author''

||id          || id

||author_id   || first_name

||title       || last_name

||description || email

||body        ||

||created_at  ||



The `Post` class is extended by a `getStrippedTitle()` method that transforms the title into a string that can be used in an URI, replacing spaces by dashes, upper case by lower case, and removing all special characters:



{{{

public function getStrippedTitle()

{

  $text = strtolower($this->getTitle());



  // strip all non word chars

  $text = preg_replace('/\W/', ' ', $text);

  // replace all white space sections with a dash

  $text = preg_replace('/\ +/', '-', $text);

  // trim dashes

  $text = preg_replace('/\-$/', '', $text);

  $text = preg_replace('/^\-/', '', $text);



  return $text;

}

}}}



The `Author` class is extended by a custom `->getName()` method as follows:



{{{

public function getName()

{

  return $this->getFirstName().' '.$this->getLastName();

}

}}}



If you need more details about the way to extend the model, refer to [http://www.symfony-project.com/book/trunk/08-Inside-the-Model-Layer#Extending%20the%20Model Chapter 8].



The `routing.yml` contains the following rule:



{{{

post:

    url:   /permalink/:stripped_title

    param: { module: post, action: read }

}}}



If you need more details about the routing system, refer to [http://www.symfony-project.com/book/trunk/09-Links-and-the-Routing-System Chapter 9].



A special `feed` module is built for the occasion, and all the actions and templates will be placed in it.



{{{$ symfony init-module myapp feed}}}



==== Expected result ====



The feed action has to output an [http://en.wikipedia.org/wiki/Atom_%28standard%29 Atom] feed. As a reminder of all the information that need to be included in an Atom feed, here is an example:



{{{



  The mouse blog

  

  2005-12-11T16:23:51Z

  

    Peter Clive

    [email protected]

  

  4543D55FF756G734

  http://www.myblog.com/favicon.ico

  

    I love mice

    

    i-love-mice

    

      Peter Clive

      [email protected]

    

    2005-12-11T16:23:51Z

    Ever since I bought my first mouse, I can't live without one.

  



  

    A mouse is better than a fish

    

    a-mouse-is-better-than-a-fish

    

      Bob Walter

      [email protected]

    

    2005-12-09T09:11:42Z

    I had a fish for four years, and now I'm sick. They smell.

  



}}}



==== Using the creators and setters ====



To build the feed, you need to initialize it with a certain format and options, and to add feed items based on the objects resulting from a database request. With the syntax of the `sfFeed` and `sfFeedItem` class, that would give:



{{{

public function executeLastPosts()

{

  $feed = new sfAtom1Feed();



  $feed->setTitle('The mouse blog');

  $feed->setLink('http://www.myblog.com/');

  $feed->setAuthorEmail('[email protected]');

  $feed->setAuthorName('Peter Clive');



  $feedImage = new sfFeedImage();

  $feedImage->setFavicon('http://www.myblog.com/favicon.ico');

  $feed->setImage($feedImage);



  $c = new Criteria;

  $c->addDescendingOrderByColumn(PostPeer::CREATED_AT);

  $c->setLimit(5);

  $posts = PostPeer::doSelect($c);



  foreach ($posts as $post)

  {

    $item = new sfFeedItem();

    $item->setTitle($post->getTitle());

    $item->setLink('@permalink?stripped_title='.$post->getStrippedTitle());

    $item->setAuthorName($post->getAuthor()->getName());

    $item->setAuthorEmail($post->getAuthor()->getEmail());

    $item->setPubdate($post->getCreatedAt('U'));

    $item->setUniqueId($post->getStrippedTitle());

    $item->setDescription($post->getDescription());



    $feed->addItem($item);

  }



  $this->feed = $feed;

}

}}}



At the end of the action, the `$feed` variable contains a `sfAtom1Feed` object which includes several `sfFeedItem` objects. To transform the object into an actual Atom feed, the `lastPostsSuccess.php` template simply contains:



{{{



asXml(ESC_RAW) ?>

}}}



The content type is automatically set by the `asXML()` method, depending on the feed format (Atom1 in this example).



When called from a feed aggregator, the result of the action is now exactly the Atom feed described above:



{{{http://www.myblog.com/feed/lastPosts}}}



==== Using the `initialize()` method ====



The use of all the setters for the feed and item construction can be a little annoying, since there is a lot of information to define. Both the `sfFeed` and the `sfFeedItem` classes provide an `initialize()` method that uses an associative array for a shorter syntax:



{{{

public function executeLastPosts()

{

  $feed = new sfAtom1Feed();



  $feed->initialize(array(

    'title'       => 'The mouse blog',

    'link'        => 'http://www.myblog.com/',

    'authorEmail' => '[email protected]',

    'authorName'  => 'Peter Clive'

  ));



  $c = new Criteria;

  $c->addDescendingOrderByColumn(PostPeer::CREATED_AT);

  $c->setLimit(5);

  $posts = PostPeer::doSelect($c);



  foreach ($posts as $post)

  {

    $item = new sfFeedItem();

    $item->initialize(array(

      'title'       => $post->getTitle(),

      'link'        => '@permalink?stripped_title='.$post->getStrippedTitle(),

      'authorName'  => $post->getAuthor()->getName(),

      'authorEmail' => $post->getAuthor()->getEmail(),

      'pubDate'     => $post->getCreatedAt(),

      'uniqueId'    => $post->getStrippedTitle(),

      'description' => $post->getDescription(),

    ));



    $feed->addItem($item);

  }



  $this->feed = $feed;

}

}}}



It has exactly the same effect as the previous listing, but the syntax is clearer.



==== Using the object converter ====



As the method names that are used to build a feed item based on an object are more or less always the same, the `sfFeedPeer` can try to do it on its own:



{{{

public function executeLastPosts()

{

  $feed = new sfAtom1Feed();



  $feed->initialize(array(

    'title'       => 'The mouse blog',

    'link'        => 'http://www.myblog.com/',

    'authorEmail' => '[email protected]',

    'authorName'  => 'Peter Clive'

  ));



  $c = new Criteria;

  $c->addDescendingOrderByColumn(PostPeer::CREATED_AT);

  $c->setLimit(5);

  $posts = PostPeer::doSelect($c);



  $postItems = sfFeedPeer::convertObjectsToItems($posts, array('routeName' => '@permalink'))

  $feed->addItems($postItems);



  $this->feed = $feed;

}

}}}



The rules governing the `sfFeedPeer::convertObjectsToItems` algorithm are as follows:



 * To set the item `title`, it looks for a `getFeedTitle()`, a `getTitle()`, a `getName()` or a `__toString()` method.



    In the example, the `Post` object has a `getName()` method.



 * To set the `link`, it uses the `routeName` option if defined in the second argument of the method call. It is supposed to be a route name for the feed items. If present, the method looks in the route url for parameters for which it could find a getter in the object methods. If not, it looks for a `getFeedLink()`, `getLink()`, `getUrl()` method in the object.



    In the example, the route name given as parameter is `@permalink`. The routing rule contains a `:stripped_title` parameter and the `Post` object has a `getStrippedTitle()` method, so the `convertObjectsToItems` method is able to define the URIs to link to.



 * To set the author's email, it looks for a `getFeedAuthorEmail` or a `getAuthorEmail`. If there is no such method, it looks for a `getAuthor()`, `getUser()` or `getPerson()` method. If the result returned is an object, it looks in this object for a `getEmail` or a `getMail` method.



    In the example, the `Post` object has a `getAuthor()`, and the `Author` object has a `getName()`. The same kind of rules is used for the author's name and URL.



 * To set the publication date, it looks for a `getFeedPubdate()`, `getPubdate()`, `getCreatedAt()` or a `getDate()` method.



    In the example, the `Post` object has a `getCreatedAt`



The same goes for the other possible fields of an Atom feed (including the categories, the summary, the unique id, etc.), and you are advised to [browse the source of the `sfFeed` class](http://www.symfony-project.com/trac/browser/plugins/sfFeed2Plugin/lib) to discover all the deduction algorithms.



All in all, the way the accessors of the `Post` and `Author` objects are built allow the built-in algorithm of the `convertObjectsToItems` method to work, and the creation of the feed to be more simple.



==== Defining custom values for the feed ====



In the list of rules presented above, you can see that the first method name that the `sfFeed` object looks for is always a `getFeedXXX()`. This allows you to specify a custom value for each of the fields of a feed item by simply extended the model.



For instance, if you don't want the author's email to be published in the feed, just add the following `getFeedAuthorEmail()` method to the `Post` object:



{{{

public function getFeedAuthorEmail()

{

  return '';

}

}}}



This method will be found before the `getAuthor()` method, and the feed will not disclose the publishers' email addresses.



The other way to use a specific method for an item property is to pass a `methods` option to the `convertObjectsToItems` method: an associative array associating item properties with object methods. So, for instance, to tell the converter to use nothing for the feed author email and the `getUserFirstName()` method for the author name, you could write:



{{{

  $postItems = sfFeedPeer::convertObjectsToItems($posts, array(

    'routeName' => '@permalink',

    'methods'   => array(

      'authorEmail' => '',

      'authorName'  => 'getUserFirstName'

    )

  ));

}}}



You can also pass some arguments to the user defined method by passing an array composed of the method name and an array of arguments:



{{{

  $postItems = sfFeedPeer::convertObjectsToItems($posts, array(

    'routeName' => '@permalink',

    'methods'   => array(

      'authorEmail' => '',

      'authorName'  => 'getUserFirstName',

      'pubdate'     => array('getPublishedAtDate', array('U')),

    )

  ));

}}}



==== Using the sfFeedPeer static methods ====



The `sfFeedPeer` class offer helper methods that facilitate the creation and population of feed items.



When the feed format is determined at runtime, create feed objects using the `sfFeedPeer::newInstance()` method, which is a factory, rather that using the `new` command:



{{{

$feed = sfFeedPeer::newInstance('atom1');

// same as

$feed = new sfAtom1Feed();

}}}



The steps described in the `executeLastPosts` listing occur in almost every feed construction process, so the `sfFeedPeer` can reduce the code above to a simpler:



{{{

public function executeLastPosts()

{

  $c = new Criteria;

  $c->addDescendingOrderByColumn(PostPeer::CREATED_AT);

  $c->setLimit(5);

  $posts = PostPeer::doSelect($c);



  $this->feed = sfFeedPeer::createFromObjects(

    $posts,

    array(

      'format'      => 'atom1',

      'title'       => 'The mouse blog',

      'link'        => 'http://www.myblog.com/',

      'authorEmail' => '[email protected]',

      'authorName'  => 'Peter Clive'

      'routeName'   => '@permalink',

      'methods'     => array('authorEmail' => '', 'authorName'  => 'getUserFirstName')

    )

  );

}

}}}



==== Using other formats ====



The methods described below can be transposed to build other RSS feeds. Simply change the parameter given to the feed factory:



{{{

// Atom 1

$feed = sfFeedPeer::newInstance('atom1');

// RSS 1.0 RDF Site Summary

$feed = sfFeedPeer::newInstance('rss10');

// RSS 0.91 Userland

$feed = sfFeedPeer::newInstance('rss091');

// RSS 2.01 rev6

$feed = sfFeedPeer::newInstance('rss201');

}}}



=== Fetching a feed from the web and displaying it ===



You may want to display the latest posts of the symfony users group in your application. The steps to retrieve this information are to fetche a feed from the Internet, create an empty feed object, and populate it with the items of the feed. You can use the `fromXML()` method and the [http://www.symfony-project.com/trac/wiki/sfWebBrowserPlugin sfWebBrowserPlugin] for that:



{{{

public function executeLastPosts()

{

  $uri = 'http://groups.google.com/group/symfony-users/feed/rss_v2_0_msgs.xml';



  $browser = new sfWebBrowser(array(

      'user_agent' => 'sfFeedReader/0.9',

      'timeout'    => 5

  ));

  $feedString = $browser->get($uri)->getResponseText();



  $feed = new sfRssFeed();

  $feed->setUrl($uri);

  $feed->fromXml($feedString);

  $this->feed = $feed;

}

}}}



Thanks to the `sfFeedPeer` shortcuts, this can be reduced to a single line:



{{{

public function executeLastPosts()

{

  $this->feed = sfFeedPeer::createFromWeb('http://groups.google.com/group/symfony-users/feed/rss_v2_0_msgs.xml');

}

}}}



The `createFromWeb()` method first parse the response and tries to recognize a known feed format (RSS or Atom - The recognized formats are the same ones as above). Note that this method depends on the `sfWebBrowserPlugin`, so this plugin must be installed to make the method work.



Once the feed is built, it is very easy to use it for the display in the template:



{{{

Latests posts from the mailing-list


    

      getItems() as $post): ?>

      
  • 

        getPubDate(), 'd/MM H:mm') ?> -

        getTitle(), $post->getLink()) ?>

        by getAuthorName() ?>

      
    • 

      



}}}



=== Aggregating several feeds ===



The `sfFeedPeer` class contains a method called `aggregate()`, which merges several feeds and reorders the items chronologically. Using it is very simple: just pass an array of feeds as parameters, and you receive a new feed object with all the items within.



For instance, here is how you could display a feed of 10 posts populated with the latest posts from both the users and the devs groups:



{{{

public function executeLastPosts()

{

  $feed1 = sfFeedPeer::createFromWeb('http://groups.google.com/group/symfony-users/feed/rss_v2_0_msgs.xml');

  $feed2 = sfFeedPeer::createFromWeb('http://groups.google.com/group/symfony-devs/feed/rss_v2_0_msgs.xml');

  $this->feed = sfFeedPeer::aggregate(array($feed1, $feed2), array('limit' => 10));

}

}}}



By default, the aggregator sorts all items in reverse chronological order. If you wish to sort them in chronological order instead, add 'sort' => 'chronological' to the parameters array.



=== Adding an image to the feed ===



To add an image to the feed, use the sfFeedImage class



{{{

$feed = new sfRss201Feed();



$feedImage = new sfFeedImage();

$feedImage->setLink('http://www.example.org/images/feed-image.png');

$feedImage->setTitle('My Title');

$feed->setImage($feedImage)

}}}}



== TODO ==



 * unit test the `sfFeedPeer` class

 * Populate feedItems from a pager rather than from an array of objects

 * Deal with time zones (i.e. store dates in GMT, and handle input and output with a time zone)



== Changelog ==



== Trunk ==



 * fabien: fixed response content-type encoding

 * francois: Fixed encoding inside CDATA sections

 * fabien: fixed routing for symfony 1.1 and optimized the 1.0 version

 * fabien: added the possibility to pass arguments to methods that convert an object to an item

 * Pascal.Borreli : symfony coding practices : removed lib closing tag (#2657)

 * Fabian Lange : added image capabilities (#2551)



=== 2007-04-15 | 0.9.4 Beta ===



 * francois: Added a `toXML` method to `sfRssFeed`, `sfRss10Feed` and `sfAtom1Feed` (based on an idea from Frank Stelzer)

 * Frank.Stelzer: Added a new `sfFeedPeer::createFromXml()` method

 * Frank.Stelzer: Fixed errors in the documentation where `sfFeed` methods were described

 * francois: `sfFeedPeer::createFromWeb()` now throws an exception whenever the fetched URL returns an error

 * Markus.Staab: Fixed a typo in `sfFeed` constructor

 * francois: Fixed a warning in `sfRssFeed` causing badly formatted feeds in dev env

 * francois: '''BC break''' `sfFeedPeer::convertObjectsToItems()` signature changed (`$objects, $options = array()`) to have similar signature to that of `sfFeedPeer::createFromObjects()`

 * francois: Added the ability to define one method per feed property in `sfFeedPeer::convertObjectsToItems()`

 * francois: `sfFeedPeer::convertObjectsToItems()` now populates the feed item content

 * francois: `sfFeedPeer::createFromWeb()` can now use a custom `userAgent` option to be seen as a custom user agent from the outside

 * francois: `sfFeedPeer::createFromWeb()` has a better detection of Atom feeds

 * francois: Fixed a bug in generated Atom1 feeds (summary attribute)

 * francois: Fixed a bug in `sfFeedPeer::aggregate()` when defining a feed format



=== 2007-03-13 | 0.9.3 Beta ===



 * francois: `sfFeedPeer::createFromWeb()` is smarter at determining the type of feed it reads

 * francois: Added smart guessing of publication date for RSS and Atom feeds, based on URL scheme

 * francois: `sfFeedPeer::aggregate()` now handles items with the same date without overriding one.

 * francois: Fixed two bugs in `sfFeedPeer` preventing items creation from objects

 * francois: Items aggregated in `sfFeedPeer::aggregate` now remember their original feed properties

 * francois: `sfFeedPeer::aggregate` can now limit the total number of items returned

 * francois: Added `sfFeed::keepOnlyItems($count)` method

 * francois: `sfRssReed` now looks for a `dc:creator` of no regular author is found



=== 2007-03-03 | 0.9.2 Beta ===



 * francois: Added a way to get an item description based on a content when no description exists

 * francois: Added `` handling in RSS 1 and 2 feeds (based on a patch from Jeff Merlet)



=== 2007-02-22 | 0.9.1 Beta ===



 * francois: Added the `sfRss10Feed` class and unit tests

 * francois: Changed feed type detection technique to avoid building a simpleXML element twice



=== 2007-02-21 | 0.9.0 Beta ===



 * francois: Added more unit tests

 * francois: Improved `sfRssFeed` conversions

 * francois: Moved `getLatestPostDate()` method to `sfFeed` and unit tested it.

 * francois: '''BC break''' Renamed specialized RSS classes to `sfRss201Feed` and `sfRss901Feed`. These classes are not really useful anyway, since all their code was refactored to `sfRssFeed`.



=== 2007-02-19 | 0.8.1 Alpha ===



 * francois: Added much more unit tests

 * francois: Improved `sfAtom1Feed` conversions

 * francois: Added `__toString()` and `initialize()` methods to `sfFeedEnclosure`

 * francois: Added `content` property to `sfFeedItem`

 * francois: '''BC break''' `fromXML()` methods now expect a string rather than a simpleXML object

 * francois: '''BC break''' `sfFeedPeer::createFromObjects()` signature changed ($objects, $parameters = array())



=== 2007-02-18 | 0.8.0 Alpha ===



 * francois: Initial release