Authorizing with oAuth, posting to Twitter

curl, php, twitter, twitter-oauth

Solution

I had three problems:

(1) I did not include it in this question, but my signature wasn't created correctly.

What I was doing was `base64_encode(hash_hmac('sha1', $base, $key));` but I should have set the hash_hmac fourth parameter to `true` to return a raw binary instead of the hexidecimal (the hexidecimal is shown as the example in the Twitter docs, which was what was confusing me). The correct function is therefore: `base64_encode(hash_hmac('sha1', $base, $key, true));`.

(2) The cURL was not set up correctly. I required CURLOPT_HTTPHEADER to set the Authorization, and CURL_VERBOSE set to true:

curl_setopt($ch, CURLOPT_HTTPHEADER, array('Authorization: ' . $DST));
curl_setopt($ch, CURLOPT_VERBOSE, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, 'status='.rawurlencode($status));
curl_setopt($ch, CURLOPT_URL, $url);

(3) As seen in the above code, I had to post the status as a string, and not an array. I found the solution to this problem on this question: Why can't I authenticate with OAuth?.

All of this is now working perfectly. Also, make sure that your access token in your Twitter application says that the access level is "Read and write". If not, change the permissions in Settings, then go back to Details and recreate your access token.

Full Script

<?php

class Tweet {

public $url = 'https://api.twitter.com/1/statuses/update.json';

function the_nonce(){
    $nonce = base64_encode(uniqid());
    $nonce = preg_replace('~[\W]~','',$nonce);
    return $nonce;
}

function get_DST($status){

    $url = $this->url;

    $consumer_key = $your_consumer_key_here;
    $nonce = $this->the_nonce();
    $sig_method = 'HMAC-SHA1';
    $timestamp = time();
    $version = "1.0";
    $token = $your_token_here;
    $access_secret = $your_access_secret_here;
    $consumer_secret = $your_consumer_secret_here;

    $param_string = 'oauth_consumer_key='.$consumer_key.
            '&oauth_nonce='.$nonce.
            '&oauth_signature_method='.$sig_method.
            '&oauth_timestamp='.$timestamp.
            '&oauth_token='.$token.
            '&oauth_version='.$version.
            '&status='.rawurlencode($status);
    $sig_base_string = 'POST&'.rawurlencode($url).'&'.rawurlencode($param_string);
    $sig_key = rawurlencode($consumer_secret).'&'.rawurlencode($access_secret);

    $tweet_sig = base64_encode(hash_hmac('sha1', $sig_base_string, $sig_key, true));

    $DST = 'OAuth oauth_consumer_key="'.rawurlencode($consumer_key).'",'.
        'oauth_nonce="'.rawurlencode($nonce).'",'.
        'oauth_signature="'.rawurlencode($tweet_sig).'",'.
        'oauth_signature_method="HMAC-SHA1",'.
        'oauth_timestamp="'.rawurlencode($timestamp).'",'.
        'oauth_token="'.rawurlencode($token).'",'.
        'oauth_version="1.0"';
    return $DST;
}

function set($status){

    $url = $this->url;

    $ch = curl_init();

curl_setopt($ch, CURLOPT_HTTPHEADER, array('Authorization: ' . $this->get_DST($status)));
curl_setopt($ch, CURLOPT_VERBOSE, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, 'status='.rawurlencode($status));
curl_setopt($ch, CURLOPT_URL, $url);

    $result = json_decode(curl_exec($ch));
if(!curl_errno($ch)){
    $info = curl_getinfo($ch);
    if($info['http_code']!='200'){
//error posting
echo 'Error: '.$result->{'error'};
    }else{
//success
echo 'Success! <a href="https://twitter.com/AOKHalifax/status/'.$result->{'id_str'}.'" target="_blank">View Tweet</a>';
    }
}else{
    //error connecting
    echo 'error posting';
    }
    curl_close($ch);
    }
}

/* 
Usage example:
$status = new Tweet();
$status->set('checking'); 
*/

?>

Problem

Original source

Related problems

• Why can't I authenticate with OAuth?