// (C) Copyright JAMES PADOLSEY
class tweetFromFile {
 
    private $curlHandle;
    private $updateFile;
    private $archiveFile;
 
    private function getNewStatus() {
 
        $upcomingTweetsFile = $this->files['upcoming'];
        $archivedTweetsFile = $this->files['archive'];
 
        $upcomingTweets_R = fopen($upcomingTweetsFile, "r");
 
        // Get upcoming Tweets:
        $contents = fread($upcomingTweets_R, filesize($upcomingTweetsFile));
        $splitContents = preg_split('/\n/', $contents, 2);
 
        // ARCHIVE OLD POSTS:
        $archive = fopen($archivedTweetsFile, "a");
        fwrite($archive, $splitContents[0]."\n");
 
        // Remove top line from upcoming:
        $upcomingTweets_W = fopen($upcomingTweetsFile, "w");
        fwrite($upcomingTweets_W, $splitContents[1]);
 
        // Clean up
        fclose($upcomingTweets_W);
        fclose($upcomingTweets_R);
        fclose($archive);
 
        return $splitContents[0];
    }
 
    public $files = array('upcoming' => '', 'archive' => '');
 
    public function __construct($username, $password, $filename) {
 
        $this->curlHandle = curl_init();
        $this->files['upcoming'] = $filename;
        $this->files['archive'] = 'ARCHIVE_' . $filename;
 
        // Shortcut:
        $ch = $this->curlHandle;
 
        curl_setopt($ch, CURLOPT_URL, "http://twitter.com/statuses/update.xml");
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 2);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_USERPWD, "$username:$password");
 
    }
 
    public function __destruct() {
        curl_close($this->curlHandle);
    }
 
    public function updateStatus() {
 
        $status = $this->getNewStatus();
 
        curl_setopt($this->curlHandle, CURLOPT_POSTFIELDS, "status=$status");
 
        $result = curl_exec($this->curlHandle);	
	$resultArray = curl_getinfo($this->curlHandle);
 
        if ($resultArray['http_code'] == 200) return true;
 
        return false;
 
    }
 
}
 
// ==================
// ===== USAGE ======
// ==================
 
$tweet = new tweetFromFile('twitterUsername', 'password', 'textfile.txt');
$success = $tweet->updateStatus();
if ($success) {
    echo 'Twitter updated!';
} else {
    echo 'Hmm, an error...';
}

The class will retrieve each new update from the specified text file. Each update needs to be on a new line; an example text file:

Blah blah blah, this is the first update...
And another update!
Third and last update!!! ARGH!

The PHP class will remove each update from this file when it’s added to Twitter so all you need to do is keep adding to the bottom of the file…

This won’t do the dripping automatically. You’ll need to setup a ‘cron job’ to request the script at selected intervals (e.g. every two hours). I’m rubbish at Apache and anything to do with the command line so I haven’t quite accomplished this part yet… maybe someone else wants to give it a go?

Well, you can! For example, you might want to add a new ‘:inline’ selector which will return those elements that are displayed inline. Have a look:

$.extend($.expr[':'],{
    inline: function(a) {
        return $(a).css('display') === 'inline';
    }
});

Using the above code, when you want to select elements that are displayed inline you can simply include it within the selector:

$(':inline'); // Selects ALL inline elements
$('a:inline'); // Selects ALL inline anchors

That was a pretty simple example but I’m sure you can see the endless possibilites that this enables! And, creating a custom jQuery selector couldn’t really be simpler!

Loaded images selector

You might want to add a ‘loaded’ selector which will work with images, and will return those images that are loaded:

// Flag images upon load:
$('img').load(function(){
    $(this).data('loaded',true);
});
 
// Extend expr:
$.extend($.expr[':'],{
    loaded: function(a) {
        return $(a).data('loaded');
    }
});
 
// Example of usage:
alert( 'Images loaded so far: ' + $('img:loaded').size() );

Querying element data

jQuery’s ‘data’ function allows us to add special data to elements without having to pollute global variables or add invalid element attributes. One of the things that jQuery lacks is the capability to easily query elements according to their data. For example, one might decide to flag all elements added dynamically (with jQuery) as ‘dom’:

// New element:
$('<img/>')
    .data('dom', true) // Flag
    .appendTo('body'); // Append to DOM

Currently there’s no easy way to select all elements that have been flagged but what if we added a new ‘:data’ selector which could query such information?

Here’s how we would do it:

// Wrap in self-invoking anonymous function:
(function($){
 
    // Extend jQuery's native ':'
    $.extend($.expr[':'],{
 
        // New method, "data"
        data: function(a,i,m) {
 
            var e = $(a).get(0), keyVal;
 
            // m[3] refers to value inside parenthesis (if existing) e.g. :data(___)
            if(!m[3]) {
 
                // Loop through properties of element object, find any jquery references:
                for (var x in e) { if((/jQuery\d+/).test(x)) { return true; } }
 
            } else {
 
                // Split into array (name,value):
                keyVal = m[3].split('=');
 
                // If a value is specified:
                if (keyVal[1]) {
 
                    // Test for regex syntax and test against it:
                    if((/^\/.+\/([mig]+)?$/).test(keyVal[1])) {
                        return
                         (new RegExp(
                             keyVal[1].substr(1,keyVal[1].lastIndexOf('/')-1),
                             keyVal[1].substr(keyVal[1].lastIndexOf('/')+1))
                          ).test($(a).data(keyVal[0]));
                    } else {
                        // Test key against value:
                        return $(a).data(keyVal[0]) == keyVal[1];
                    }
 
                } else {
 
                    // Test if element has data property:
                    if($(a).data(keyVal[0])) {
                        return true;
                    } else {
                        // If it doesn't remove data (this is to account for what seems
                        // to be a bug in jQuery):
                        $(a).removeData(keyVal[0]);
                        return false;
                    }
 
                }
            }
 
            // Strict compliance:
            return false;
 
        }
 
    });
})(jQuery);

Usage

Now, selecting elements which have that ‘dom’ flag is really easy:

$(':data(dom)'); // All elements with 'dom' flag
$('div:data(dom)'); // All DIV elements with 'dom' flag
$(':not(:data(dom))'); // All elements WITHOUT 'dom' flag

The ‘:data’ extension also allows you to query by comparison, for example:

$(':data(ABC=123)'); // All elements with a data key of 'ABC' equal to 123

It also allows you to use regular expressions:

// Let's assume we have slightly varying data across a set of elements:
$('div').each(function(i){
    $(this).data('divInfo','index:' + i);
    // Will result in value being 'index:0', 'index:1', 'index:2' etc. etc.
});
 
// We can select all of those DIVs like this:
$('div:data(divInfo=/index:\\d+/)');
 
// Note: It's necessary to use non-literal notation when writing these
// regular expressions, so if you want to match a real backslash you'd
// have to use '\\\\'. Similarly if you want to test for all digit's
// you'd have to use \\d instead of \d.

Additionally, you can select elements on a basis of whether or not they have ANY data applied to them:

$(':data');       // All elements with data
$(':not(:data)'); // All elements without data

Some other examples:

• :red

  // Check if color of element is red:
  $.extend($.expr[':'],{
      red: function(a) {
          return $(a).css('color') === 'red';
      }
  });
   
  // Usage:
  $('p:red'); // Select all red paragraphs

• :childOfDiv

  // Check if element is a child of a div:
  $.extend($.expr[':'],{
      childOfDiv: function(a) {
          return $(a).parents('div').size();
      }
  });
   
  // Yes, I know this is exactly the same as $('div p')
  // This is just a demonstration! ;)
   
  // Usage:
  $('p:childOfDiv'); // Select all paragraphs that have a DIV as a parent

• :width()

  // Check width of element:
  $.extend($.expr[':'],{
      width: function(a,i,m) {
          if(!m[3]||!(/^(<|>)\d+$/).test(m[3])) {return false;}
          return m[3].substr(0,1) === '>' ? 
                   $(a).width() > m[3].substr(1) : $(a).width() < m[3].substr(1);
      }
  });
   
  // Usage:
  $('div:width(>200)'); // Select all DIVs that have a width greater than 200px
   
  // Alternative usage:
  $('div:width(>200):width(<300)'); // Select all DIVs that have a width greater
                                    // than 200px but less than 300px

• :biggerThan()

  // Check whether element is bigger than another:
  $.extend($.expr[':'],{
      biggerThan: function(a,i,m) {
          if(!m[3]) {return false;}
          return $(a).width() * $(a).height() > $(m[3]).width() * $(m[3]).height();
      }
  });
   
  // Usage:
  $('div:biggerThan(div#banner))'); // Select all DIVs that are bigger than #banner
   
  // Alternative usage: (something a little more complex)
  // (Making use of custom width() selector)
   
  // Select all DIVs with a width less than 600px but an overall
  // size greater than that of the first paragraph which has a 
  // size greater than img#header:
  $('div:width(<600):biggerThan(p:biggerThan(img#header):eq(0))');

Like I said, the possibilities are endless…

UPDATE

I’ve created a couple more examples, take a look:

• :external

  // Check whether links are external:
  // (Only works with elements that have href):
  $.extend($.expr[':'],{
      external: function(a,i,m) {
          if(!a.href) {return false;}
          return a.hostname && a.hostname !== window.location.hostname;
      }
  });
   
  // Usage:
  $('a:external'); // Selects all anchors which link to external site/page

• :inView

  // Check whether element is currently within the viewport:
  $.extend($.expr[':'],{
      inView: function(a) {
          var st = (document.documentElement.scrollTop || document.body.scrollTop),
              ot = $(a).offset().top,
              wh = (window.innerHeight && window.innerHeight < $(window).height()) ? window.innerHeight : $(window).height();
          return ot > st && ($(a).height() + ot) < (st + wh);
      }
  });
   
  // Usage:
  $('div:inView'); // Selects all DIV elements within the current viewport
   
  // Alternative Usage:
  if ( $('div#footer').is(':inView') ) {
      // Do stuff...
  }

UPDATE #2

I’ve created a plugin which makes it a little easier to add new ‘:’ selectors. Although, it’s not really a ‘plugin’, it’s just a function which resides under the jQuery namespace:

(function($){
    $.newSelector = function() {
        if(!arguments) { return; }
        $.extend($.expr[':'],typeof(arguments[0])==='object' ? arguments[0]
          : (function(){
              var newOb = {}; newOb[arguments[0]] = arguments[1];
              return newOb;
          })()
        );
    }
})(jQuery);

Creating a new selector with the ‘newSelector’ plugin:

// Method 1:
$.newSelector('big', function(elem){
    return $(elem).width() + $(elem).height() > 1000;
});
// Method 2:
$.newSelector({
    red: function(elem){
        return $(elem).css('color') === 'red';
    },
    yellow: function(elem){
        return $(elem).css('color') === 'yellow';
    },
    green: function(elem){
        return $(elem).css('color') === 'green';
    },
});

There are a few things which annoy me about the web interface though. The worst thing by far is that it’s very slow and sometimes just doesn’t work. There are also some posting issues; if I have a really long link which I want to share, it won’t let me press the "update" button (because my tweet is now over 140 characters) – but I know that Twitter will convert the URL to a tinyurl which will surely result in a tweet shorter than 140 characters but Twitter still insists on disallowing this action!

I got really tired of this, twitter wouldn’t let me tweet even though shortened versions of posted URLs would fit into the 140 character limit quite nicely! Out of desperation I decided to create a cool little GreaseMonkey script which solves this problem.

You can install the script here – (Sorry, it’s Firefox only, duh!)

The new script uses Greasemonkey’s native GM_xmlhttpRequest (Cross-Domain savvy!) to request shortened URLs from the Reque.st API (recently developed). If you have a look at the source you’ll notice some of it’s a little bit "hacky" – I’m having to create a new invisible element over Twitter’s "update" button to capture a submission attempt – to be honest, this is just so much easier than messing with all Twitter’s event handling and existing functions; it’s an absolute minefield – they’ve got a wacky combination of Prototype, Scriptaculous & jQuery! (Cough! What can’t jQuery do by itself!? )

How to use it:

Once you’ve installed it simply use Twitter as you would normally. If you type in a long URL which makes the tweet go over the 140 character limit then simply press "update" as you would normally. If the tweet is still too long after URL shortening then an alert box will show up notifying you. Any bugs can be reported here or on the UserScript.org page as a comment.