Tutorials

Create a Twitter Feed With Hash Tag And Cache Support

Written by Kevin Liew on 20 Feb 2012
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71 comments

Introduction

Due to popular demand, this tutorial is actually a revisit from my previous Twitter tutorial - Create a dead simple Twitter feed with jQuery. A lot of readers requested to be able to parse hashtag. So, I've decided to make a new version that able to do both plus some enhancements.

The foundation of this script will be the same, but with some modification to accept both hashtag and normal user feed. It will be smart enough to switch but with one tiny caveat which I will mention later on. You can see the preview or download it to play with the code.

UPDATE: We have written an updated version of Twitter API tutorial based on Twitter Newest API 1.1. - Easiest Way to Retrieve Twitter Timeline and Hashtags

Features

  • Able to parse User Timeline and hashtag (multiple hashtags by using OR operator to separate hashtags)
  • Cache result to avoid rate limits restriction from Twitter.
  • Decided to not using Cronjob to renew the cache, it uses date comparison with PHP.
  • Using links/hashtag/alias script to parse the tweet.

HTML

HTML is basically the same as the old one, nothing fancy.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
    <meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
    <title></title>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js" type="text/javascript"></script>
    <script src="twitter.js"></script>
</head>
<body>
     
    <div id="jstwitter">
    </div>
     
</body>
</html>

CSS

CSS, nothing special, just simply style it up to make it presentable. However, this is a list of class that you can use to style it up:

  • .twtr-hashtag: #abc
  • .twtr-hyperlink: hyperlink
  • .twtr-atreply: #abc
  • .text: tweet
  • .user: username
  • .time: relative time (10 minutes ago)
body {
	background:#ccc;
}

#jstwitter {
	width: 300px;
	font-family: georgia;
	font-size: 12px;
	color: #333333;
	padding: 10px 10px 0 10px;
	margin:0 auto;
	background:#fff;
	border:5px solid #eaeaea;
	border-radius:15px;
	box-shadow:0 0 5px rgba(0, 0, 0, 0.3);
}

#jstwitter h1 {
	text-align:center;
	margin-top:5px;
}

#jstwitter .tweet {
	margin: 0 auto 15px auto;
	padding: 0 0 15px 0;
	border-bottom: 1px dotted #ccc;
}

#jstwitter .tweet a {
	text-decoration: none;
	color: #03a8e5;
}

#jstwitter .tweet a:hover {
	text-decoration: underline;
}

#jstwitter .tweet .text {
	display:block;
}

#jstwitter .tweet .time, #jstwitter .tweet .user {
	font-style: italic;
	color: #666666;
}

#jstwitter .tweet:last-child {
	border:0;
}

Javascript

Okay, the core. This jQuery script added a few if-else statements to toggle between hashtag and user timeline. I put inline comment in every crucial code for better understanding of what it does.

The way it works:

  1. Firstly, you can set either hashtag or username. If you filled in hashtag, username will be ignore. If you want username, you need to leave hashtag empty.
  2. You can set other setting such as number of tweet, cache expiry date, append to element.
  3. In loadTweet function, it constructs different request and pass it to PHP script, and then PHP script will format the request with the right Twitter API and grab the content. The PHP script is responsible to handle the cache as well. Depend on how long you set in the cacheExpiry, it will renew the cache accordingly.
  4. Finally, the Javascript will parse the returned JSON based on the type of API. (hashtag and user timeline's JSON is a bit different in structure)

Some tips and tricks

Multiple Hashtags: You can separate the hastags with OR operator. eg: '%23jquery OR %23css'

Multiple Users: You can use 'from:account' and separate with OR operator. eg: 'from:quenesswebblog OR from:favbulous'

JQTWEET = {
	
	// Set twitter hash/user, number of tweets & id/class to append tweets
	// You need to clear tweet-date.txt before toggle between hash and user
	// for multiple hashtags, you can separate the hashtag with OR, eg:
	// hash: '%23jquery OR %23css'
	hash: '%23jquery', //leave this blank if you want to show user's tweet
	user: 'quenesswebblog', //username
	numTweets: 5, //number of tweets
	cacheExpiry: 2, //get the new cache in 2 hours
	appendTo: '#jstwitter',
	
	// core function of jqtweet
	// https://dev.twitter.com/docs/using-search
	loadTweets: function() {
	
		var request;
		
		// different JSON request {hash|user}
		if (JQTWEET.hash) {
			request = {
				q: JQTWEET.hash,
				expiry: JQTWEET.cacheExpiry,				
				api: 'http://search.twitter.com/search.json'
			}
		} else {
			request = {
				screen_name: JQTWEET.user,
				include_rts: true,
				count: JQTWEET.numTweets,
				include_entities: true,
				expiry: JQTWEET.cacheExpiry, 
				api: 'http://api.twitter.com/1/statuses/user_timeline.json/'
			}
		}

		$.ajax({
			url: 'tweets-grab.php',
			type: 'GET',
			dataType: 'json',
			data: request,
			success: function(data, textStatus, xhr) {

				var text, name, html = '<div class="tweet"><span class="text">TWEET_TEXT</span><span class="time"><a href="URL" target="_blank">AGO</a></span> by <span class="user">USER</span></div>';
		
				try {
		
					//Twitter Search API has different JSON Structure
					if (JQTWEET.hash) data = data['results'];
		
					// append tweets into page
					for (var i = 0; i < data.length && i < JQTWEET.numTweets; i++) {
						
						name = (JQTWEET.hash) ? data[i].from_user : data[i].user.screen_name;
	
						$(JQTWEET.appendTo).append(	
						    html.replace('TWEET_TEXT', JQTWEET.ify.clean(data[i].text) )
						        .replace(/USER/g, name)
						        .replace('AGO', JQTWEET.timeAgo(data[i].created_at) )
						        .replace('URL', 'http://twitter.com/' + data[i].from_user + '/status/' + data[i].id_str )
						);								
	
					}					
				
				} catch (e) {
					alert('No data returned, you might want to clear tweets-date.txt.');
				}			
			
			}	

		});

	}, 
	
		
	/**
      * relative time calculator FROM TWITTER
      * @param {string} twitter date string returned from Twitter API
      * @return {string} relative time like "2 minutes ago"
      */
    timeAgo: function(dateString) {
		var rightNow = new Date();
		var then = new Date(dateString);
		
		if ($.browser.msie) {
			// IE can't parse these crazy Ruby dates
			then = Date.parse(dateString.replace(/( \+)/, ' UTC$1'));
		}

		var diff = rightNow - then;

		var second = 1000,
		minute = second * 60,
		hour = minute * 60,
		day = hour * 24,
		week = day * 7;

		if (isNaN(diff) || diff < 0) {
			return ""; // return blank string if unknown
		}

		if (diff < second * 2) {
			// within 2 seconds
			return "right now";
		}

		if (diff < minute) {
			return Math.floor(diff / second) + " seconds ago";
		}

		if (diff < minute * 2) {
			return "about 1 minute ago";
		}

		if (diff < hour) {
			return Math.floor(diff / minute) + " minutes ago";
		}

		if (diff < hour * 2) {
			return "about 1 hour ago";
		}

		if (diff < day) {
			return  Math.floor(diff / hour) + " hours ago";
		}

		if (diff > day && diff < day * 2) {
			return "yesterday";
		}

		if (diff < day * 365) {
			return Math.floor(diff / day) + " days ago";
		}

		else {
			return "over a year ago";
		}
	}, // timeAgo()
    
	
    /**
      * The Twitalinkahashifyer!
      * http://www.dustindiaz.com/basement/ify.html
      * Eg:
      * ify.clean('your tweet text');
      */
    ify:  {
      link: function(tweet) {
        return tweet.replace(/\b(((https*\:\/\/)|www\.)[^\"\']+?)(([!?,.\)]+)?(\s|$))/g, function(link, m1, m2, m3, m4) {
          var http = m2.match(/w/) ? 'http://' : '';
          return '<a class="twtr-hyperlink" target="_blank" href="' + http + m1 + '">' + ((m1.length > 25) ? m1.substr(0, 24) + '...' : m1) + '</a>' + m4;
        });
      },

      at: function(tweet) {
        return tweet.replace(/\B[@@]([a-zA-Z0-9_]{1,20})/g, function(m, username) {
          return '<a target="_blank" class="twtr-atreply" href="http://twitter.com/intent/user?screen_name=' + username + '">@' + username + '</a>';
        });
      },

      list: function(tweet) {
        return tweet.replace(/\B[@@]([a-zA-Z0-9_]{1,20}\/\w+)/g, function(m, userlist) {
          return '<a target="_blank" class="twtr-atreply" href="http://twitter.com/' + userlist + '">@' + userlist + '</a>';
        });
      },

      hash: function(tweet) {
        return tweet.replace(/(^|\s+)#(\w+)/gi, function(m, before, hash) {
          return before + '<a target="_blank" class="twtr-hashtag" href="http://twitter.com/search?q=%23' + hash + '">#' + hash + '</a>';
        });
      },

      clean: function(tweet) {
        return this.hash(this.at(this.list(this.link(tweet))));
      }
    } // ify

	
};



$(document).ready(function () {
	// start jqtweet!
	JQTWEET.loadTweets();
});

PHP

Right, the final part of this tutorial - the PHP. It:

  • Checks for Cache Expiry interval
  • Constructs the API call
  • Retrieves JSON data from Twitter
  • Saves both JSON data and date

We need two text files:

  • tweets-cache.txt: contains latest data in JSON format
  • tweets-date.txt: contains the date of last retrieval

In the introduction, I mentioned about a small caveat of this script - Whenever you switch between hashtag and username, you need to clear the tweets-date.txt.

<?php


$cache = 'tweets-cache.txt';
$date = 'tweets-date.txt';

$currentTime = time(); // Current time

// Get cache time
$datefile = fopen($date, 'r');
$cacheDate = fgets($datefile);
fclose($datefile);


//check if cache has expired
if (floor(abs(($currentTime-$cacheDate) / 3600)) <= $_GET['expiry'] && $cacheDate) {

	$cachefile = fopen($cache, 'r');
	$data = fgets($cachefile);
	fclose($cachefile);

} else { //renew the cache

	//toggle between API
	if ($_GET['q']) 
	{
		$data = file_get_contents($_GET['api'] . '?q=' . urlencode($_GET['q']));   
	
	} else if ($_GET['screen_name']) 
	{
		$data = file_get_contents($_GET['api'] . '?screen_name=' . $_GET['screen_name'] . '&count=' . $_GET['count'] . '&include_rts=' . $_GET['include_rts'] . '&include_entities=' . $_GET['include_entities']);   
	}
	
	// update cache file
	$cachefile = fopen($cache, 'wb');  
	fwrite($cachefile,utf8_encode($data));  
	fclose($cachefile); 

	// update date file
	$datefile = fopen($date, 'wb');  
	fwrite($datefile, utf8_encode(time()));  
	fclose($datefile); 	 
}


header('Content-type: application/json');
echo $data;
?>

Conclusion

So, that's how you do it, support both hashtag and username, easy to style and uses cache to overcome Twitter rate limits. You just have to remember, whenever you switch between hashtag and username, remember to clear the content of tweets-date.txt.

That's it, hope you will find this useful and any questions, just drop me a comment and I will try my very best to answer it quickly. Stay tuned with queness! For more cool and updated javascript inspiration, tutorials, plugins, you can follow us on twitter or like us on facebook.

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71 comments
Kevin Brands 3 years ago
I really like the script. It's simple and understandable. But does what is has to do perfectly.

There's one problem for me:
If I use this in a Wordpress environment, the script doesn't output any tweets on a single post page. Do you maybe know what's going on there? It does work on the other pages. So that's the strange part..

Thanks in advance!
Reply
Michael 3 years ago
New information from Twitter regarding API.
https://dev.twitter.com/blog/planning-for-api-v1-retirement

Is this something that will require updating the code?
Reply
Alex 2 years ago
Hi Kevin!

Thank you for the article! Unfortunately, I don't have a PHP server available. It there a way to overcome its absence and use something like JavaScript? I am planning to use the single user web page local to the computer. Many thanks in advance for your help and links, if possible!!!
Reply