public function Apache_Solr_Service::ping in Apache Solr Search 5

Call the /admin/ping servlet, can be used to quickly tell if a connection to the server is able to be made.

Parameters

float $timeout maximum time to wait for ping in seconds, -1 for unlimited (default is 2):

Return value

float Actual time taken to ping the server, FALSE if timeout occurs

File

SolrPhpClient/Apache/Solr/Service.php, line 520

Class

Apache_Solr_Service

Starting point for the Solr API. Represents a Solr server resource and has methods for pinging, adding, deleting, committing, optimizing and searching.

Code

public function ping($timeout = 2) {
  $timeout = (double) $timeout;
  if ($timeout <= 0) {
    $timeout = -1;
  }
  $start = microtime(true);

  //to prevent strict errors
  $errno = 0;
  $errstr = '';

  //try to connect to the host with timeout
  $fp = fsockopen($this->_host, $this->_port, $errno, $errstr, $timeout);
  if ($fp) {

    //If we have a timeout set, then determine the amount of time we have left

    //in the request and set the stream timeout for the write operation
    if ($timeout > 0) {

      //do the calculation
      $writeTimeout = $timeout - (microtime(true) - $start);

      //check if we're out of time
      if ($writeTimeout <= 0) {
        fclose($fp);
        return false;
      }

      //convert to microseconds and set the stream timeout
      $writeTimeoutInMicroseconds = (int) $writeTimeout * 1000000;
      stream_set_timeout($fp, 0, $writeTimeoutInMicroseconds);
    }
    $request = 'HEAD ' . $this->_path . self::PING_SERVLET . ' HTTP/1.1' . "\r\n" . 'host: ' . $this->_host . "\r\n" . 'Connection: close' . "\r\n" . "\r\n";
    fwrite($fp, $request);

    //check the stream meta data to see if we timed out during the operation
    $metaData = stream_get_meta_data($fp);
    if (isset($metaData['timeout']) && $metaData['timeout']) {
      fclose($fp);
      return false;
    }

    //if we have a timeout set and have made it this far, determine the amount of time

    //still remaining and set the timeout appropriately before the read operation
    if ($timeout > 0) {

      //do the calculation
      $readTimeout = $timeout - (microtime(true) - $start);

      //check if we've run out of time
      if ($readTimeout <= 0) {
        fclose($fp);
        return false;
      }

      //convert to microseconds and set the stream timeout
      $readTimeoutInMicroseconds = $readTimeout * 1000000;
      stream_set_timeout($fp, 0, $readTimeoutInMicroseconds);
    }

    //at the very least we should get a response header line of

    //HTTP/1.1 200 OK
    $response = fread($fp, 15);

    //check the stream meta data to see if we timed out during the operation
    $metaData = stream_get_meta_data($fp);
    fclose($fp);

    //we're done with the connection - ignore the rest
    if (isset($metaData['timeout']) && $metaData['timeout']) {
      return false;
    }

    //finally, check the response header line
    if ($response != 'HTTP/1.1 200 OK') {
      return false;
    }

    //we made it, return the approximate ping time
    return microtime(true) - $start;
  }

  //we weren't able to make a connection
  return false;
}