PHP学习：php-beanstalkd消息队列类实例分享

<?php
namespace Common\Business;
/**
 * beanstalk: A minimalistic PHP beanstalk client.
 *
 * Copyright (c) 2009-2015 David Persson
 *
 * Distributed under the terms of the MIT License.
 * Redistributions of files must retain the above copyright notice.
 */
 
use RuntimeException;
 
/**
 * An interface to the beanstalk queue service. Implements the beanstalk
 * protocol spec 1.9. Where appropriate the documentation from the protocol
 * has been added to the docblocks in this class.
 *
 * @link https://github.com/kr/beanstalkd/blob/master/doc/protocol.txt
 */
class BeanStalk {
 
  /**
   * Minimum priority value which can be assigned to a job. The minimum
   * priority value is also the _highest priority_ a job can have.
   *
   * @var integer
   */
  const MIN_PRIORITY = 0;
 
  /**
   * Maximum priority value which can be assigned to a job. The maximum
   * priority value is also the _lowest priority_ a job can have.
   *
   * @var integer
   */
  const MAX_PRIORITY = 4294967295;
 
  /**
   * Holds a boolean indicating whether a connection to the server is
   * currently established or not.
   *
   * @var boolean
   */
  public $connected = false;
 
  /**
   * Holds configuration values.
   *
   * @var array
   */
  protected $_config = [];
 
  /**
   * The current connection resource handle (if any).
   *
   * @var resource
   */
  protected $_connection;
 
  /**
   * Constructor.
   *
   * @param array $config An array of configuration values:
   *    - `'persistent'` Whether to make the connection persistent or
   *             not, defaults to `true` as the FAQ recommends
   *             persistent connections.
   *    - `'host'`    The beanstalk server hostname or IP address to
   *             connect to, defaults to `127.0.0.1`.
   *    - `'port'`    The port of the server to connect to, defaults
   *             to `11300`.
   *    - `'timeout'`   Timeout in seconds when establishing the
   *             connection, defaults to `1`.
   *    - `'logger'`   An instance of a PSR-3 compatible logger.
   *
   * @link https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-3-logger-interface.md
   * @return void
   */
  public function __construct(array $config = []) {
    $defaults = [
      'persistent' => true,
      'host' => '127.0.0.1',
      'port' => 11300,
      'timeout' => 1,
      'logger' => null
    ];
    $this->_config = $config + $defaults;
  }
 
  /**
   * Destructor, disconnects from the server.
   *
   * @return void
   */
  public function __destruct() {
    $this->disconnect();
  }
 
  /**
   * Initiates a socket connection to the beanstalk server. The resulting
   * stream will not have any timeout set on it. Which means it can wait
   * an unlimited amount of time until a packet becomes available. This
   * is required for doing blocking reads.
   *
   * @see \Beanstalk\Client::$_connection
   * @see \Beanstalk\Client::reserve()
   * @return boolean `true` if the connection was established, `false` otherwise.
   */
  public function connect() {
    if (isset($this->_connection)) {
      $this->disconnect();
    }
    $errNum = '';
    $errStr = '';
    $function = $this->_config['persistent'] ? 'pfsockopen' : 'fsockopen';
    $params = [$this->_config['host'], $this->_config['port'], &$errNum, &$errStr];
 
    if ($this->_config['timeout']) {
      $params[] = $this->_config['timeout'];
    }
    $this->_connection = @call_user_func_array($function, $params);
 
    if (!empty($errNum) || !empty($errStr)) {
      $this->_error("{$errNum}: {$errStr}");
    }
 
    $this->connected = is_resource($this->_connection);
 
    if ($this->connected) {
      stream_set_timeout($this->_connection, -1);
    }
    return $this->connected;
  }
 
  /**
   * Closes the connection to the beanstalk server by first signaling
   * that we want to quit then actually closing the socket connection.
   *
   * @return boolean `true` if diconnecting was successful.
   */
  public function disconnect() {
    if (!is_resource($this->_connection)) {
      $this->connected = false;
    } else {
      $this->_write('quit');
      $this->connected = !fclose($this->_connection);
 
      if (!$this->connected) {
        $this->_connection = null;
      }
    }
    return !$this->connected;
  }
 
  /**
   * Pushes an error message to the logger, when one is configured.
   *
   * @param string $message The error message.
   * @return void
   */
  protected function _error($message) {
    if ($this->_config['logger']) {
      $this->_config['logger']->error($message);
    }
  }
 
  public function errors()
  {
    return $this->_config['logger'];
  }
  /**
   * Writes a packet to the socket. Prior to writing to the socket will
   * check for availability of the connection.
   *
   * @param string $data
   * @return integer|boolean number of written bytes or `false` on error.
   */
  protected function _write($data) {
    if (!$this->connected) {
      $message = 'No connecting found while writing data to socket.';
      throw new RuntimeException($message);
    }
 
    $data .= "\r\n";
    return fwrite($this->_connection, $data, strlen($data));
  }
 
  /**
   * Reads a packet from the socket. Prior to reading from the socket
   * will check for availability of the connection.
   *
   * @param integer $length Number of bytes to read.
   * @return string|boolean Data or `false` on error.
   */
  protected function _read($length = null) {
    if (!$this->connected) {
      $message = 'No connection found while reading data from socket.';
      throw new RuntimeException($message);
    }
    if ($length) {
      if (feof($this->_connection)) {
        return false;
      }
      $data = stream_get_contents($this->_connection, $length + 2);
      $meta = stream_get_meta_data($this->_connection);
 
      if ($meta['timed_out']) {
        $message = 'Connection timed out while reading data from socket.';
        throw new RuntimeException($message);
      }
      $packet = rtrim($data, "\r\n");
    } else {
      $packet = stream_get_line($this->_connection, 16384, "\r\n");
    }
    return $packet;
  }
 
  /* Producer Commands */
 
  /**
   * The `put` command is for any process that wants to insert a job into the queue.
   *
   * @param integer $pri Jobs with smaller priority values will be scheduled
   *    before jobs with larger priorities. The most urgent priority is
   *    0; the least urgent priority is 4294967295.
   * @param integer $delay Seconds to wait before putting the job in the
   *    ready queue. The job will be in the "delayed" state during this time.
   * @param integer $ttr Time to run - Number of seconds to allow a worker to
   *    run this job. The minimum ttr is 1.
   * @param string $data The job body.
   * @return integer|boolean `false` on error otherwise an integer indicating
   *     the job id.
   */
  public function put($pri, $delay, $ttr, $data) {
    $this->_write(sprintf("put %d %d %d %d\r\n%s", $pri, $delay, $ttr, strlen($data), $data));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'INSERTED':
      case 'BURIED':
        return (integer) strtok(' '); // job id
      case 'EXPECTED_CRLF':
      case 'JOB_TOO_BIG':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * The `use` command is for producers. Subsequent put commands will put
   * jobs into the tube specified by this command. If no use command has
   * been issued, jobs will be put into the tube named `default`.
   *
   * @param string $tube A name at most 200 bytes. It specifies the tube to
   *    use. If the tube does not exist, it will be created.
   * @return string|boolean `false` on error otherwise the name of the tube.
   */
  public function useTube($tube) {
    $this->_write(sprintf('use %s', $tube));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'USING':
        return strtok(' ');
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Pause a tube delaying any new job in it being reserved for a given time.
   *
   * @param string $tube The name of the tube to pause.
   * @param integer $delay Number of seconds to wait before reserving any more
   *    jobs from the queue.
   * @return boolean `false` on error otherwise `true`.
   */
  public function pauseTube($tube, $delay) {
    $this->_write(sprintf('pause-tube %s %d', $tube, $delay));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'PAUSED':
        return true;
      case 'NOT_FOUND':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /* Worker Commands */
 
  /**
   * Reserve a job (with a timeout).
   *
   * @param integer $timeout If given specifies number of seconds to wait for
   *    a job. `0` returns immediately.
   * @return array|false `false` on error otherwise an array holding job id
   *     and body.
   */
  public function reserve($timeout = null) {
    if (isset($timeout)) {
      $this->_write(sprintf('reserve-with-timeout %d', $timeout));
    } else {
      $this->_write('reserve');
    }
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'RESERVED':
        return [
          'id' => (integer) strtok(' '),
          'body' => $this->_read((integer) strtok(' '))
        ];
      case 'DEADLINE_SOON':
      case 'TIMED_OUT':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Removes a job from the server entirely.
   *
   * @param integer $id The id of the job.
   * @return boolean `false` on error, `true` on success.
   */
  public function delete($id) {
    $this->_write(sprintf('delete %d', $id));
    $status = $this->_read();
 
    switch ($status) {
      case 'DELETED':
        return true;
      case 'NOT_FOUND':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Puts a reserved job back into the ready queue.
   *
   * @param integer $id The id of the job.
   * @param integer $pri Priority to assign to the job.
   * @param integer $delay Number of seconds to wait before putting the job in the ready queue.
   * @return boolean `false` on error, `true` on success.
   */
  public function release($id, $pri, $delay) {
    $this->_write(sprintf('release %d %d %d', $id, $pri, $delay));
    $status = $this->_read();
 
    switch ($status) {
      case 'RELEASED':
      case 'BURIED':
        return true;
      case 'NOT_FOUND':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Puts a job into the `buried` state Buried jobs are put into a FIFO
   * linked list and will not be touched until a client kicks them.
   *
   * @param integer $id The id of the job.
   * @param integer $pri *New* priority to assign to the job.
   * @return boolean `false` on error, `true` on success.
   */
  public function bury($id, $pri) {
    $this->_write(sprintf('bury %d %d', $id, $pri));
    $status = $this->_read();
 
    switch ($status) {
      case 'BURIED':
        return true;
      case 'NOT_FOUND':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Allows a worker to request more time to work on a job.
   *
   * @param integer $id The id of the job.
   * @return boolean `false` on error, `true` on success.
   */
  public function touch($id) {
    $this->_write(sprintf('touch %d', $id));
    $status = $this->_read();
 
    switch ($status) {
      case 'TOUCHED':
        return true;
      case 'NOT_TOUCHED':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Adds the named tube to the watch list for the current connection.
   *
   * @param string $tube Name of tube to watch.
   * @return integer|boolean `false` on error otherwise number of tubes in watch list.
   */
  public function watch($tube) {
    $this->_write(sprintf('watch %s', $tube));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'WATCHING':
        return (integer) strtok(' ');
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Remove the named tube from the watch list.
   *
   * @param string $tube Name of tube to ignore.
   * @return integer|boolean `false` on error otherwise number of tubes in watch list.
   */
  public function ignore($tube) {
    $this->_write(sprintf('ignore %s', $tube));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'WATCHING':
        return (integer) strtok(' ');
      case 'NOT_IGNORED':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /* Other Commands */
 
  /**
   * Inspect a job by its id.
   *
   * @param integer $id The id of the job.
   * @return string|boolean `false` on error otherwise the body of the job.
   */
  public function peek($id) {
    $this->_write(sprintf('peek %d', $id));
    return $this->_peekRead();
  }
 
  /**
   * Inspect the next ready job.
   *
   * @return string|boolean `false` on error otherwise the body of the job.
   */
  public function peekReady() {
    $this->_write('peek-ready');
    return $this->_peekRead();
  }
 
  /**
   * Inspect the job with the shortest delay left.
   *
   * @return string|boolean `false` on error otherwise the body of the job.
   */
  public function peekDelayed() {
    $this->_write('peek-delayed');
    return $this->_peekRead();
  }
 
  /**
   * Inspect the next job in the list of buried jobs.
   *
   * @return string|boolean `false` on error otherwise the body of the job.
   */
  public function peekBuried() {
    $this->_write('peek-buried');
    return $this->_peekRead();
  }
 
  /**
   * Handles response for all peek methods.
   *
   * @return string|boolean `false` on error otherwise the body of the job.
   */
  protected function _peekRead() {
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'FOUND':
        return [
          'id' => (integer) strtok(' '),
          'body' => $this->_read((integer) strtok(' '))
        ];
      case 'NOT_FOUND':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Moves jobs into the ready queue (applies to the current tube).
   *
   * If there are buried jobs those get kicked only otherwise delayed
   * jobs get kicked.
   *
   * @param integer $bound Upper bound on the number of jobs to kick.
   * @return integer|boolean False on error otherwise number of jobs kicked.
   */
  public function kick($bound) {
    $this->_write(sprintf('kick %d', $bound));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'KICKED':
        return (integer) strtok(' ');
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * This is a variant of the kick command that operates with a single
   * job identified by its job id. If the given job id exists and is in a
   * buried or delayed state, it will be moved to the ready queue of the
   * the same tube where it currently belongs.
   *
   * @param integer $id The job id.
   * @return boolean `false` on error `true` otherwise.
   */
  public function kickJob($id) {
    $this->_write(sprintf('kick-job %d', $id));
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'KICKED':
        return true;
      case 'NOT_FOUND':
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /* Stats Commands */
 
  /**
   * Gives statistical information about the specified job if it exists.
   *
   * @param integer $id The job id.
   * @return string|boolean `false` on error otherwise a string with a yaml formatted dictionary.
   */
  public function statsJob($id) {
    $this->_write(sprintf('stats-job %d', $id));
    return $this->_statsRead();
  }
 
  /**
   * Gives statistical information about the specified tube if it exists.
   *
   * @param string $tube Name of the tube.
   * @return string|boolean `false` on error otherwise a string with a yaml formatted dictionary.
   */
  public function statsTube($tube) {
    $this->_write(sprintf('stats-tube %s', $tube));
    return $this->_statsRead();
  }
 
  /**
   * Gives statistical information about the system as a whole.
   *
   * @return string|boolean `false` on error otherwise a string with a yaml formatted dictionary.
   */
  public function stats() {
    $this->_write('stats');
    return $this->_statsRead();
  }
 
  /**
   * Returns a list of all existing tubes.
   *
   * @return string|boolean `false` on error otherwise a string with a yaml formatted list.
   */
  public function listTubes() {
    $this->_write('list-tubes');
    return $this->_statsRead();
  }
 
  /**
   * Returns the tube currently being used by the producer.
   *
   * @return string|boolean `false` on error otherwise a string with the name of the tube.
   */
  public function listTubeUsed() {
    $this->_write('list-tube-used');
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'USING':
        return strtok(' ');
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Returns a list of tubes currently being watched by the worker.
   *
   * @return string|boolean `false` on error otherwise a string with a yaml formatted list.
   */
  public function listTubesWatched() {
    $this->_write('list-tubes-watched');
    return $this->_statsRead();
  }
 
  /**
   * Handles responses for all stat methods.
   *
   * @param boolean $decode Whether to decode data before returning it or not. Default is `true`.
   * @return array|string|boolean `false` on error otherwise statistical data.
   */
  protected function _statsRead($decode = true) {
    $status = strtok($this->_read(), ' ');
 
    switch ($status) {
      case 'OK':
        $data = $this->_read((integer) strtok(' '));
        return $decode ? $this->_decode($data) : $data;
      default:
        $this->_error($status);
        return false;
    }
  }
 
  /**
   * Decodes YAML data. This is a super naive decoder which just works on
   * a subset of YAML which is commonly returned by beanstalk.
   *
   * @param string $data The data in YAML format, can be either a list or a dictionary.
   * @return array An (associative) array of the converted data.
   */
  protected function _decode($data) {
    $data = array_slice(explode("\n", $data), 1);
    $result = [];
 
    foreach ($data as $key => $value) {
      if ($value[0] === '-') {
        $value = ltrim($value, '- ');
      } elseif (strpos($value, ':') !== false) {
        list($key, $value) = explode(':', $value);
        $value = ltrim($value, ' ');
      }
      if (is_numeric($value)) {
        $value = (integer) $value == $value ? (integer) $value : (float) $value;
      }
      $result[$key] = $value;
    }
    return $result;
  }
}
 
?>