Twitter JSON to Atom feed proxy for Twitter API 1.1

twitterfeed.php

<?php
  /*
   Twitter JSON to Atom proxy for Twitter API 1.1 - @yliu
   Original version by Russell Beattie ( https://gist.github.com/russellbeattie/3898467 )

   Fork of upstream to remove use of short tags; add t.co expansion and URL formatting for feed reader
   License: BSD
   */

    date_default_timezone_set('America/Los_Angeles');
    ini_set('display_errors', 0);

    $user_screen_name = 'CHANGE ME';
    $user_full_name = 'CHANGE ME TOO';

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

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


// API: https://dev.twitter.com/docs/api/1.1/get/statuses/home_timeline

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

    $api_params = array(
        'count' => 80,
        'tweet_mode' => 'extended',
        'contributor_details' => 'false',
    );

// 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);


 // echo "curl --get '" . $api_url . "' --data '" . $rparams . "' --header 'Authorization: OAuth " . $hparams . "' --verbose" . PHP_EOL;


// 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){

        http_response_code($code);
        echo 'Error' . PHP_EOL;
        echo $code . PHP_EOL;
        print_r($response);
        print_r($info);


    } else {

        $all = json_decode($response, true);
    if (!$all)
    {
      http_response_code(400);
      echo 'Could not decode JSON response';
      print_r($response);
    }
        $updated = date(DATE_ATOM, strtotime($all[0]['created_at']));

        header('Content-type: application/atom+xml; charset=UTF-8', true);

        echo '<?xml version="1.0" encoding="utf-8"?' . '>' . PHP_EOL;

?>
<feed xml:lang="en-US" xmlns="http://www.w3.org/2005/Atom">
<title>Twitter / <?php echo $user_screen_name?></title>
<id>tag:twitter.com,2007:Status</id>
<link type="text/html" rel="alternate" href="http://twitter.com"/>
<link type="application/atom+xml" rel="self" href="http://<?php echo $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"]?>"></link>
<updated><?php echo $updated?></updated>
<subtitle>Twitter updates from <?php echo $user_full_name?>.</subtitle>
<?php
    foreach($all as $row)
    {
        $id = $row['id_str'];
        $text = $row['full_text'];
        $is_retweet = isset($row['retweeted_status']);
        if($is_retweet)
        {
            $text = "RT @" . $row['retweeted_status']['user']['screen_name'] . ": "  . $row['retweeted_status']['full_text'];
        }
        $title = $row['user']['screen_name'] . ': ' . $text;
        $entry = $title;
        $expansion_target = $row;
        if($is_retweet)
        {
            $expansion_target = $row['retweeted_status'];
        }	
        
        if(isset($expansion_target['entities']) and isset($expansion_target['entities']['urls'])) 
        {
            // expand t.co URLs
            $urls = $expansion_target['entities']['urls'];
            foreach($urls as $url)
            {
                $url_orig = $url['url'];
                $url_expanded = $url['expanded_url'];
                $url_expanded_tagged = "<a href='$url_expanded'>$url_expanded</a>";
                $title = str_replace($url_orig, $url_expanded, $title);
                $entry = str_replace($url_orig, $url_expanded_tagged, $entry);
            }
      }
      if(isset($expansion_target['extended_entities']) and isset($expansion_target['extended_entities']['media']))
      {
            $media = $expansion_target['extended_entities']['media'];
            foreach($media as $medium)
            {
                $medium_orig = $medium['url'];
                $medium_raw = $medium['media_url_https'];
                $medium_display = $medium['display_url'];
                $medium_expanded = $medium['expanded_url'];
                $medium_expanded_tagged = "<a href='$medium_expanded'><img src='$medium_raw'></img></a>";
                $title = str_replace($medium_orig, $medium_display, $title);
                $entry = str_replace($medium_orig, $medium_expanded_tagged, $entry);
            }
      }
      $name = htmlspecialchars($row['user']['name']);
      $screen_name = $row['user']['screen_name'];
      $url = $row['user']['url'];
      $profile_image_url = $row['user']['profile_image_url'];
      $source = htmlspecialchars($row['source']);
      $entry = htmlspecialchars($entry);
      $title = htmlspecialchars($title);
      $created = date(DATE_ATOM, strtotime($row['created_at']));
 

            

?>
    <entry>
    <title type="html"><?php echo $title?></title>
    <content type="html"><?php echo $entry ?></content>
    <id>tag:twitter.com,2007:http://twitter.com/<?php echo $screen_name?>/status/<?php echo $id?></id>
    <published><?php echo $created?></published>
    <updated><?php echo $created?></updated>
    <link type="text/html" rel="alternate" href="http://twitter.com/<?php echo $screen_name?>/status/<?php echo $id?>"/>
    <link type="image/png" rel="image" href="<?php echo $profile_image_url?>"/>
    <author>
    <name><?php echo $name?></name>
    <uri><?php echo $url?></uri>
    </author>
    </entry>
<?php
        }
?>
</feed>
<?php
        exit();

    }