Access Twitter with OAuth, get json feed and output html for embedding in web page.

tweets2html.php

<?php
/**
 * tweets2html.php
 *
 * Modified by John Crawley 2013/07/24
 * to output html from Twitter feed for embedding in web page.
 *
 * Based on twitterfeed.php by Russell Beattie (2012-10-16)
 * (http://www.russellbeattie.com/blog/twitterfeedphp-get-your-authenticated-twitter-stream-as-an-atom-feed)
 *
 * Also incorporates code adapted from:
 * Yiming Liu's version:
 * (http://blog.yimingliu.com/2013/02/07/a-twitter-timeline-to-atom-feed-proxy/)
 * Twitterfeed+ by Patrick Nagel, 2013-04-06
 * (https://patrick-nagel.net/scripts/twitterfeedplus/twitterfeedplus.php)
 * and URL un-shortening by Marty (2012-11-12)
 * (http://www.internoetics.com/2012/11/12/resolve-short-urls-to-their-destination-url-php-api/)
 *
 *
 * Timestamps are simplified and relative.
 * Short links are expanded: t.co from Twitter entities,
 * and one further step if necessary.
 * Long URLs are truncated for display.
 * Links are added to @mentions and #hashtags
 * HTML (ul) is wrapped in variable $tweetlist for embedding in web page,
 * and cached to avoid multiple calls to Twitter.
 * Licence: new material GPL3, other as per original authors.

 *
 * Usage instructions:
 * 	1) Go to https://dev.twitter.com/apps and create a new App.
 * 	2) Use the Authentication button to create the tokens/secrets needed.
 * 	3) Copy the results into the appropriate spots below.
 *  4) The script is currently set to output a user timeline.
 *     Check the Twitter api docs: https://dev.twitter.com/docs/api/1.1
 *     and adjust $api_url and $api_params to suit your needs.
 *     ( Do not set 'include_entities' => 'false' )
 *  5) Set $cache_path, make sure the directory exists, is writable
 *     by the server and outside the web root.
 *  6) Adjust any other settings to taste.
 *  7) Put this file in your include path, and include it somewhere near
 *     the start of your php with: require_once('tweets2html.php');
 *     NB This file contains your twitter app keys and secrets so be sure
 *     to put it above your web root, and give it minimum read permissions.
 *  8) Call the html where you need it with: <?php echo($tweetlist); ?>
 *
 */

// Twitter App Settings (https://dev.twitter.com/apps):
//  FILL THESE IN

        $settings = array(
          'consumer_key' => '*REPLACEME*',
          'consumer_secret' => '*REPLACEME*',
          'access_token' => '*REPLACEME*',
          'access_token_secret' => '*REPLACEME*'
        );


// API docs: https://dev.twitter.com/docs/api/1.1

	$api_url = 'https://api.twitter.com/1.1/statuses/user_timeline.json';

	$api_params = array(
        'screen_name' => '*REPLACEME*',
		'count' => 7,
        'exclude_replies' => 'true',
        'include_rts' => 'false',
		'contributor_details' => 'false',
		'trim_user' => 'true',
		'include_entities' => 'true'
	);


// Other settings:

//      date_default_timezone_set('Asia/Tokyo'); // may (should?) be set elsewhere in your site

        $url_max_display_length = 25; // long urls will be truncated to this

        $error_message = 'Unable to display tweets.'; // display if getting tweets fails

        $timestamp_title = 'View on Twitter'; // title for tweet's timestamp link


//  Makes relative timestamps for tweets - edit to taste

        function reltime($datetime)
        {
            $diff=(time() - $datetime);

            $day=60*60*24;

            if ($diff<$day) //Under a day
            {
                $reltime = 'Today';
            }else{
                $reltime = round($diff/$day) . ' days ago';
            }
            return $reltime;
        }

// Caching - set path to cache directory:
// Make sure this folder exists, is writable by server and
// preferably outside the web root.
        $cache_path = '../cache'; // path relative to web root.
        $cache_life = 60*60; // (seconds)
        // cache will be used if newer than 1 hr

// settings end here //
//////////////////////////////////////////////////////////////////////


$cache_file = $_SERVER['DOCUMENT_ROOT'].'/'.$cache_path.'/tweetlist.html';
if (file_exists($cache_file)) {
    $timediff = (time() - filemtime($cache_file));
    if ($timediff < $cache_life) {
        $tweetlist = file_get_contents($cache_file);
        return; // do not run rest of script
    }
}


// OAuth:

	function oauth_encode($data){
		if(is_array($data)){
			return array_map('oauth_encode', $data);
		} else if(is_scalar($data)) {
			return str_ireplace(array('+', '%7E'), array(' ', '~'), rawurlencode($data));
		} else {
			return '';
		}
	}

// OAuth base settings

    $oauth_params = array(
        'oauth_consumer_key' => $settings['consumer_key'],
        'oauth_nonce' => md5(microtime() . mt_rand()),
        'oauth_signature_method' => 'HMAC-SHA1',
        'oauth_timestamp' => time(),
        'oauth_token' => $settings['access_token'],
        'oauth_version' => '1.0',
    );

// Sign OAuth params

    $sign_params = array_merge($oauth_params, $api_params);

    uksort($sign_params, 'strcmp');

    foreach ($sign_params as $k => $v) {
        $sparam[] = oauth_encode($k) . '=' . oauth_encode($v);
    }

    $sparams = implode('&', $sparam);

    $base_string = 'GET&' . oauth_encode($api_url) . '&' . oauth_encode($sparams);

    $signing_key = oauth_encode($settings['consumer_secret']) . '&' . oauth_encode($settings['access_token_secret']);

    $oauth_params['oauth_signature'] = oauth_encode(base64_encode(hash_hmac('sha1', $base_string, $signing_key, TRUE)));


// Set Authorization header:

    uksort($oauth_params, 'strcmp');

    foreach ($oauth_params as $k => $v) {
      $hparam[] = $k . '="' . $v . '"';
    }

    $hparams = implode(', ', $hparam);

    $headers = array();
    $headers['Expect'] = '';
    $headers['Authorization'] = 'OAuth ' . $hparams;

    foreach ($headers as $k => $v) {
        $curlheaders[] = trim($k . ': ' . $v);
    }

// Format params:

    foreach ($api_params as $k => $v) {
        $rparam[] = $k . '=' . $v;
    }

    $rparams = implode('&', $rparam);

//////////////////////////////////////////////////////////////////////////

// Un-shorten URL
	function resolveShortURL($url) {
		$ch = curl_init("$url");
		curl_setopt($ch, CURLOPT_HEADER, 1);
		curl_setopt($ch, CURLOPT_NOBODY, 1);
		curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 0);
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_TIMEOUT, 5 );
		$yy = curl_exec($ch);
		$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
		curl_close($ch);

		if($httpCode == 404) {
			return "";
		}

		$w = explode("\n",$yy);

		$Redirect = array_values( preg_grep( '/[Ll]ocation/', $w ) );
		if(count($Redirect) > 0) {
			$url = $Redirect[0];
			$url = str_ireplace("Location:", "", "$url");
			$url = trim("$url");
            return $url;
		}
        return "";
	}

// Get domain from URL
	function getdomain($url) {
		$url = trim($url);
		$url = preg_replace("/^(http(s)?:\/\/)*(www.)*/is", "", $url);
		$url = preg_replace("/\/.*$/is" , "" ,$url);
		return $url;
	}

// Array of top URL shorteners
	$shorteners = array(	"tiny.cc", "is.gd", "own.ly", "rubyurl.com", "bit.ly", "tinyurl.com",
		"moourl.com", "cli.gs", "ka.lm", "u.nu", "yep.it", "shrten.com", "miniurl.com", "snipurl.com",
		"short.ie", "idek.net", "w3t.org", "shiturl.com", "dwarfurl.com", "doiop.com", "smallurl.in",
		"notlong.com", "fyad.org", "safe.mn", "hex.io", "own.ly", "lnkd.in", "fb.me", "amzn.to",
		"goo.gl", "j.mp", "mcaf.ee", "lnk.ms", "youtu.be", "wp.me", "fwd4.me", "su.pr", "t.co",
		"snurl.com", "tr.im", "twurl.cc", "fat.ly", "ow.ly", "bbc.in");

//  Truncate url for display
    function truncate_url($url, $maxlength)
    {
        $url = preg_replace('/^https?:\/\//','',$url,1);
        if (strlen($url) > $maxlength)
        {
            $url = substr($url,0,($maxlength -1)) . '…';
        }
        return $url;
    }

//////////////////////////////////////////////////////////////////////////

// GET:
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $api_url . '?' . $rparams);
curl_setopt($ch, CURLOPT_HTTPHEADER, $curlheaders);
curl_setopt($ch, CURLOPT_HEADER, false);
curl_setopt($ch, CURLINFO_HEADER_OUT, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_TIMEOUT, 10 );

$response = curl_exec($ch);
$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
$info = curl_getinfo($ch);
$error = curl_error($ch);
$errno = curl_errno($ch);

curl_close($ch);

if($code != 200){

    error_log( "Error\n$code" );
    error_log(print_r($response,TRUE));
    error_log(print_r($info,TRUE));
    $tweetlist = "<ul><li>$error_message</li></ul>";
    return;
}

$all = json_decode($response, TRUE);

$tweetlist = "<ul>\n";

foreach($all as $tweet){

    $id = $tweet['id_str'];
    $text = htmlspecialchars($tweet['text']);
//			$tweeter_name = htmlspecialchars($tweet['user']['name']);
//			$tweeter_screen_name = $tweet['user']['screen_name'];
    $tweeter_id = $tweet['user']['id_str'];
//			$tweeter_url = $tweet['user']['url'];
//			$tweeter_profile_image_url = $tweet['user']['profile_image_url'];
    $source = htmlspecialchars($tweet['source']);
    $created_time = strtotime($tweet['created_at']);

    if(isset($tweet['entities'])){
        if(isset($tweet['entities']['urls'])){
        // expand t.co URLs, and possible second shortened URL after that.
            $urls = $tweet['entities']['urls'];
            foreach($urls as $url){
                $url_orig = $url['url'];
                $url_expanded = $url['expanded_url'];
                if(in_array(getdomain($url_expanded), $shorteners)) {
                    $url_reexpanded = resolveShortURL($url_expanded);
                    if($url_reexpanded) {
                        $url_expanded = $url_reexpanded;
                    }
                }
                $url_expanded_tagged = '<a href="'.$url_expanded.'">'.truncate_url($url_expanded,$url_max_display_length).'</a>';
                $text = str_replace($url_orig, $url_expanded_tagged, $text);
            }
        }
        if(isset($tweet['entities']['user_mentions'])){
        // add link to @ mentions
            $mentions = $tweet['entities']['user_mentions'];
            foreach($mentions as $mention){
                $mention_name = htmlspecialchars($mention['name']);
                $mention_screen_name = $mention['screen_name'];
                $mention_tagged = '<a href="http://twitter.com/'.$mention_screen_name.'" title="'.$mention_name.'">@'.$mention_screen_name.'</a>';
                $text = str_replace("@$mention_screen_name", $mention_tagged, $text);
            }
        }
        if(isset($tweet['entities']['hashtags'])){
        // add link to # hashtags
            $hashtags = $tweet['entities']['hashtags'];
            foreach($hashtags as $hashtag){
                $hashtext_orig = $hashtag['text'];
                $hashtext = htmlspecialchars($hashtext_orig);
                $hashtag_tagged = '<a href="http://twitter.com/search?q=%23'.$hashtext.'&src=hash">#'.$hashtext.'</a>';
                $text = str_replace("#$hashtext_orig", $hashtag_tagged, $text);
            }
        }
    }

    $timestamp = '<span class="tweet_time"><a href="http://twitter.com/'.$tweeter_id.'/status/'.$id.'" title="'.$timestamp_title.'">'.reltime($created_time).'</a></span>';
    $text = '<span class="tweet_text">'.$text.'</span>';
    $tweetlist .= '<li>'.$timestamp.' '.$text."</li>\n";

}

$tweetlist .= "</ul>\n";
//$tweetlist .= "<!--\n".print_r($all,TRUE)."\n-->"; // for debugging

file_put_contents($cache_file, $tweetlist, LOCK_EX);

Based on Russell Beattie's twitterfeed.php : https://gist.github.com/russellbeattie/3898467
and Liu Yiming's adaptation to use Twitter entities: https://gist.github.com/yimingliu/4735445
with material from Patrick Nagel:https://patrick-nagel.net/scripts/twitterfeedplus/twitterfeedplus.php
and Marty: http://www.internoetics.com/2012/11/12/resolve-short-urls-to-their-destination-url-php-api/

Creates a variable $tweetlist which holds an html <ul> containing the tweets for embedding in a web page as a customizable widget.