MiniMailQueue v0.1

<?
/* MMQ -- Mini_Mail_Queue
 *
 * Created by Scott Arciszewski, 24 September 2012 - 27 September 2012
 *      kobrasrealm@gmail.com                   @voodooKobra on Twitter
 */
class MiniMailQueue {
  const VALIDATION_REGEX = '/[^@]@[A-Za-z0-9\.\-\_]{2,}\.[A-Za-z0-9]{2,}/';
    // Regular expression for email validation
  private $config = array(
    'mail_temp_folder' => '/tmp/mmq/',     // contains a 1 if locked
    'mail_last_send_file' => '/tmp/mmq/lastSend',
    'mail_lock_file' => '/tmp/mmq/mailLock',     // contains a 1 if locked
    'mail_master_file' => '/tmp/mmq/master.db',     // contains a 1 if locked
    'mail_send_amount' => 30,                    // # emails per batch
    'bytes_per_file' => 20,                    // # pseudorandom bytes in a filename
    'mail_send_timeout' => 30                    // Time between batches

  ); // Default configuration. Can be changed here or through setopt(array('option' => 'value'));
  private $master; // Master SQLite DB
  public $slave; // Individual SQLite DB

  public function __construct($options=array()) {
    $this->setopt($options);
    if(!file_exists($this->config['mail_master_file'])) {
      $this->createMaster();
    } else {
      $this->master = new PDO('sqlite:'.$this->config['mail_master_file']);
    }
  }
  private function createMaster() {
    // Construct the master DB file if it doesn't exist
    if(!file_exists($this->config['mail_master_file'])) {
      $this->master = new PDO('sqlite:'.$this->config['mail_master_file']);
      chmod($this->config['mail_master_file'], 0777);
      $this->master->exec("CREATE TABLE slaves (filename TEXT, sending INTEGER, birth INTEGER, death INTEGER);");
    }
  }
  public function setopt($options) {
    // Pass an array of new values:
    foreach($options as $i => $v) {
      if(isset($this->config[$i])) $this->config[$i] = $v;
    }
  }
  // $to = array(); of addresses
  // $subject = string
  // $message = string
  // $headers = if array, parsed into string. Otherwise, string
  public function enqueue($to, $subject, $message, $headers) {
    // Create an SQLite database for this jobtask
    // Put the address of this DB into the master db
    $dbFile = $this->randomName(); // bytes
    $dbPath = $this->config['mail_temp_folder'].$dbFile.'.db';
    if(!is_array($to)) die("Must pass an array!");
    if(is_array($headers)) $headers = $this->headerParse($headers);

    $this->slave = new PDO('sqlite:'.$dbPath) or die("ERROR: Could not create file {$dbPath}");
      chmod($dbPath, 0777);
      $this->master->exec("INSERT INTO slaves (filename, sending, birth, death) VALUES ('{$dbFile}', '1', '".time()."', '0');");
    // Now, creat the table structures for the slave
    $this->slave->exec("CREATE TABLE metadata (subject TEXT, message TEXT, headers TEXT);");
    $this->slave->exec("CREATE TABLE recipients (address TEXT, received TEXT, time INTEGER);");
    // Prepare statements, then execute. SQLi be damned
    $st = $this->slave->prepare("INSERT INTO metadata (subject, message, headers) VALUES (?, ?, ?);");
    $st->execute( array($subject, $message, $headers) );
    $st = $this->slave->prepare("INSERT INTO recipients (address, received, time) VALUES (?, '0', '0');");
    // Wonderful! Now to add data:
    foreach($to as $t) {
      $st->execute(array($t));
    }
    // Now we should be done.
    return true;
  }
  protected function headerParse($array) {
    // Parse into headers
    $head = '';
    foreach($array as $i => $v) {
      $head .= "{$i}: {$v}\r\n";
    }
    return trim($head);
  }
  public function sendBatch() {
    // Send ____ emails
    // First step: Lock from double-changing
    file_put_contents($this->config['mail_lock_file'], 1);
    $sl = array();
    foreach($this->master->query("SELECT ROWID as id, filename, sending, birth, death FROM slaves WHERE sending = '1'") as $slv) {
      $sl[] = new MMQSlave($slv);
    }
    if(empty($sl)) return false;
    $N = count($sl);
    $L = $this->config['mail_send_amount'];
    $LN = $L / ($N > 1 ? $N : 1);
    foreach($sl as $s) {
      $dbPath = $this->config['mail_temp_folder'].$s->filename.'.db';
      $slave = new PDO('sqlite:'.$dbPath);
      $batch = $slave->query("SELECT * FROM metadata");
      $meta = $batch->fetch(PDO::FETCH_ASSOC); // Pull metadata
      $j = 0;
      foreach($slave->query("SELECT ROWID AS id, address, received, time FROM recipients WHERE received = '0' LIMIT 0, {$LN}") as $r) {
        mail($r['address'], $meta['subject'], $meta['message'], $meta['headers']);
          // Send the email
        $slave->exec("UPDATE recipients SET received = '1', time = '".time()."' WHERE ROWID = '{$r['id']}'");
          // Mark it as sent
        $j++;
      }
      if($j < $LN) {
        // We ran out of recipients!
        $this->master->exec("UPDATE slaves SET sending = '0', death = '".time()."' WHERE id = '{$s->id}'");
      }
      $LN = ($LN - $j) + ($L / ($N > 1 ? $N : 1));
      // If batch A only had 3 left to send and batch B has 27 left to send, still send them all this tick.
    }
    // Last step:
    file_put_contents($this->config['mail_lock_file'], 0);
    file_put_contents($this->config['mail_last_send_file'], time());
  }
  public function ready($autosend=false) {
    // Is the file locked?
      $locked = intval(file_get_contents($this->config['mail_lock_file']));
      if($locked) return false;
    // Has it been more than ____ seconds?
      $lastsent = intval(file_get_contents($this->config['mail_last_send_file']));
      if(time() - $lastsent < $this->config['mail_send_timeout']) return false;
    // Yes, you can send something
      if($autosend) return $this->sendBatch(); // Send a batch, if not told otherwise
      return true;
  }
  public function randomName() {
    // Generate a random filename for this database!
    if(function_exists('bin2hex') && function_exists('openssl_random_pseudo_bytes')) {
      // Strong randomization!
       return $this->convBase(
                bin2hex(openssl_random_pseudo_bytes($this->config['bytes_per_file'])),
                '0123456789abcdef',
                'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_' // Non-standard base64
              );
    } else {
        if(is_readable('/dev/urandom')) {
          // Screw you, PHP < 4.0! We'll do things my way.
            $fp = fopen('/dev/urandom', 'rb');
            list(, $hex) = unpack('H*', fread($fp, $this->config['bytes_per_file']));
            fclose($fp);
          return $this->convBase(
                   bin2hex($hex),
                   '0123456789abcdef',
                   'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_' // Non-standard base64
                 );
        } else { // Weak randomization!
          $acc = ''; // Accumulator
          $target = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_';
          while(strlen($acc) < $this->config['bytes_per_file']) {
            $acc .= $target[mt_rand(0, 63)];
          }
          return $acc;
            // Weaksauce, man
        }
    }
  }
  /*
                                ATTENTION!
    /\        /\        /\        /\        /\        /\        /\        /\
   /##\      /##\      /##\      /##\      /##\      /##\      /##\      /##\
  /####\    /####\    /####\    /####\    /####\    /####\    /####\    /####\
 /######\  /######\  /######\  /######\  /######\  /######\  /######\  /######\
 \######/  \######/  \######/  \######/  \######/  \######/  \######/  \######/
  \####/    \####/    \####/    \####/    \####/    \####/    \####/    \####/
   \##/      \##/      \##/      \##/      \##/      \##/      \##/      \##/
    \/        \/        \/        \/        \/        \/        \/        \/

                BELOW IS AUXULLIARY AND NOT WRITTEN BY SCOTT
   */

  public function convBase($numberInput, $fromBaseInput, $toBaseInput) {
  // http://php.net/manual/en/function.base-convert.php#106546
    if ($fromBaseInput==$toBaseInput) return $numberInput;
    $fromBase = str_split($fromBaseInput,1);
    $toBase = str_split($toBaseInput,1);
    $number = str_split($numberInput,1);
    $fromLen=strlen($fromBaseInput);
    $toLen=strlen($toBaseInput);
    $numberLen=strlen($numberInput);
    $retval='';
    if ($toBaseInput == '0123456789')
    {
        $retval=0;
        for ($i = 1;$i <= $numberLen; $i++)
            $retval = bcadd($retval, bcmul(array_search($number[$i-1], $fromBase),bcpow($fromLen,$numberLen-$i)));
        return $retval;
    }
    if ($fromBaseInput != '0123456789')
        $base10=$this->convBase($numberInput, $fromBaseInput, '0123456789');
    else
        $base10 = $numberInput;
    if ($base10<strlen($toBaseInput))
        return $toBase[$base10];
    while($base10 != '0')
    {
        $retval = $toBase[bcmod($base10,$toLen)].$retval;
        $base10 = bcdiv($base10,$toLen,0);
    }
    return $retval;
  }
}

/*
 *  MMQSlave :: Data structure for each recipient
 */
class MMQSlave {
  public $id;
  public $filename;
  public $sending;
  public $birth;
  public $death;
  public function __construct($sl) {
    $this->id = $sl['id'];
    $this->filename = $sl['filename'];
    $this->sending = $sl['sending'];
    $this->birth = $sl['birth'];
    $this->death = $sl['death'];
  }
}
?>