File Source for Balancer.php

<?php
/**
* Copyright (c) 2007-2011, Servigistics, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - Neither the name of Servigistics, Inc. nor the names of
* its contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* @copyright Copyright 2007-2011 Servigistics, Inc. (http://servigistics.com)
* @license http://solr-php-client.googlecode.com/svn/trunk/COPYING New BSD
* @version $Id: Balancer.php 54 2011-02-04 16:29:18Z donovan.jimenez $
*
* @package Apache
* @subpackage Solr
* @author Donovan Jimenez <djimenez@conduit-it.com>, Dan Wolfe
*/
// See Issue #1 (http://code.google.com/p/solr-php-client/issues/detail?id=1)
// Doesn't follow typical include path conventions, but is more convenient for users
require_once(dirname(dirname(__FILE__)) . '/Service.php');
require_once(dirname(dirname(__FILE__)) . '/NoServiceAvailableException.php');
/**
* Reference Implementation for using multiple Solr services in a distribution. Functionality
* includes:
* routing of read / write operations
* failover (on selection) for multiple read servers
*/
class Apache_Solr_Service_Balancer
{
/**
* SVN Revision meta data for this class
*/
const SVN_REVISION = '$Revision: 54 $';
/**
* SVN ID meta data for this class
*/
const SVN_ID = '$Id: Balancer.php 54 2011-02-04 16:29:18Z donovan.jimenez $';
protected $_createDocuments = true;
protected $_readableServices = array();
protected $_writeableServices = array();
protected $_currentReadService = null;
protected $_currentWriteService = null;
protected $_readPingTimeout = 2;
protected $_writePingTimeout = 4;
// Configuration for server selection backoff intervals
protected $_useBackoff = false; // Set to true to use more resillient write server selection
protected $_backoffLimit = 600; // 10 minute default maximum
protected $_backoffEscalation = 2.0; // Rate at which to increase backoff period
protected $_defaultBackoff = 2.0; // Default backoff interval
/**
* Escape a value for special query characters such as ':', '(', ')', '*', '?', etc.
*
* NOTE: inside a phrase fewer characters need escaped, use {@link Apache_Solr_Service::escapePhrase()} instead
*
* @param string $value
* @return string
*/
static public function escape($value)
{
return Apache_Solr_Service::escape($value);
}
/**
* Escape a value meant to be contained in a phrase for special query characters
*
* @param string $value
* @return string
*/
static public function escapePhrase($value)
{
return Apache_Solr_Service::escapePhrase($value);
}
/**
* Convenience function for creating phrase syntax from a value
*
* @param string $value
* @return string
*/
static public function phrase($value)
{
return Apache_Solr_Service::phrase($value);
}
/**
* Constructor. Takes arrays of read and write service instances or descriptions
*
* @param array $readableServices
* @param array $writeableServices
*/
public function __construct($readableServices = array(), $writeableServices = array())
{
//setup readable services
foreach ($readableServices as $service)
{
$this->addReadService($service);
}
//setup writeable services
foreach ($writeableServices as $service)
{
$this->addWriteService($service);
}
}
public function setReadPingTimeout($timeout)
{
$this->_readPingTimeout = $timeout;
}
public function setWritePingTimeout($timeout)
{
$this->_writePingTimeout = $timeout;
}
public function setUseBackoff($enable)
{
$this->_useBackoff = $enable;
}
/**
* Generates a service ID
*
* @param string $host
* @param integer $port
* @param string $path
* @return string
*/
protected function _getServiceId($host, $port, $path)
{
return $host . ':' . $port . $path;
}
/**
* Adds a service instance or service descriptor (if it is already
* not added)
*
* @param mixed $service
*
* @throws Apache_Solr_InvalidArgumentException If service descriptor is not valid
*/
public function addReadService($service)
{
if ($service instanceof Apache_Solr_Service)
{
$id = $this->_getServiceId($service->getHost(), $service->getPort(), $service->getPath());
$this->_readableServices[$id] = $service;
}
else if (is_array($service))
{
if (isset($service['host']) && isset($service['port']) && isset($service['path']))
{
$id = $this->_getServiceId((string)$service['host'], (int)$service['port'], (string)$service['path']);
$this->_readableServices[$id] = $service;
}
else
{
throw new Apache_Solr_InvalidArgumentException('A Readable Service description array does not have all required elements of host, port, and path');
}
}
}
/**
* Removes a service instance or descriptor from the available services
*
* @param mixed $service
*
* @throws Apache_Solr_InvalidArgumentException If service descriptor is not valid
*/
public function removeReadService($service)
{
$id = '';
if ($service instanceof Apache_Solr_Service)
{
$id = $this->_getServiceId($service->getHost(), $service->getPort(), $service->getPath());
}
else if (is_array($service))
{
if (isset($service['host']) && isset($service['port']) && isset($service['path']))
{
$id = $this->_getServiceId((string)$service['host'], (int)$service['port'], (string)$service['path']);
}
else
{
throw new Apache_Solr_InvalidArgumentException('A Readable Service description array does not have all required elements of host, port, and path');
}
}
else if (is_string($service))
{
$id = $service;
}
if ($id && isset($this->_readableServices[$id]))
{
unset($this->_readableServices[$id]);
}
}
/**
* Adds a service instance or service descriptor (if it is already
* not added)
*
* @param mixed $service
*
* @throws Apache_Solr_InvalidArgumentException If service descriptor is not valid
*/
public function addWriteService($service)
{
if ($service instanceof Apache_Solr_Service)
{
$id = $this->_getServiceId($service->getHost(), $service->getPort(), $service->getPath());
$this->_writeableServices[$id] = $service;
}
else if (is_array($service))
{
if (isset($service['host']) && isset($service['port']) && isset($service['path']))
{
$id = $this->_getServiceId((string)$service['host'], (int)$service['port'], (string)$service['path']);
$this->_writeableServices[$id] = $service;
}
else
{
throw new Apache_Solr_InvalidArgumentException('A Writeable Service description array does not have all required elements of host, port, and path');
}
}
}
/**
* Removes a service instance or descriptor from the available services
*
* @param mixed $service
*
* @throws Apache_Solr_InvalidArgumentException If service descriptor is not valid
*/
public function removeWriteService($service)
{
$id = '';
if ($service instanceof Apache_Solr_Service)
{
$id = $this->_getServiceId($service->getHost(), $service->getPort(), $service->getPath());
}
else if (is_array($service))
{
if (isset($service['host']) && isset($service['port']) && isset($service['path']))
{
$id = $this->_getServiceId((string)$service['host'], (int)$service['port'], (string)$service['path']);
}
else
{
throw new Apache_Solr_InvalidArgumentException('A Readable Service description array does not have all required elements of host, port, and path');
}
}
else if (is_string($service))
{
$id = $service;
}
if ($id && isset($this->_writeableServices[$id]))
{
unset($this->_writeableServices[$id]);
}
}
/**
* Iterate through available read services and select the first with a ping
* that satisfies configured timeout restrictions (or the default)
*
* @return Apache_Solr_Service
*
* @throws Apache_Solr_NoServiceAvailableException If there are no read services that meet requirements
*/
protected function _selectReadService($forceSelect = false)
{
if (!$this->_currentReadService || !isset($this->_readableServices[$this->_currentReadService]) || $forceSelect)
{
if ($this->_currentReadService && isset($this->_readableServices[$this->_currentReadService]) && $forceSelect)
{
// we probably had a communication error, ping the current read service, remove it if it times out
if ($this->_readableServices[$this->_currentReadService]->ping($this->_readPingTimeout) === false)
{
$this->removeReadService($this->_currentReadService);
}
}
if (count($this->_readableServices))
{
// select one of the read services at random
$ids = array_keys($this->_readableServices);
$id = $ids[rand(0, count($ids) - 1)];
$service = $this->_readableServices[$id];
if (is_array($service))
{
//convert the array definition to a client object
$service = new Apache_Solr_Service($service['host'], $service['port'], $service['path']);
$this->_readableServices[$id] = $service;
}
$service->setCreateDocuments($this->_createDocuments);
$this->_currentReadService = $id;
}
else
{
throw new Apache_Solr_NoServiceAvailableException('No read services were available');
}
}
return $this->_readableServices[$this->_currentReadService];
}
/**
* Iterate through available write services and select the first with a ping
* that satisfies configured timeout restrictions (or the default)
*
* @return Apache_Solr_Service
*
* @throws Apache_Solr_NoServiceAvailableException If there are no write services that meet requirements
*/
protected function _selectWriteService($forceSelect = false)
{
if($this->_useBackoff)
{
return $this->_selectWriteServiceSafe($forceSelect);
}
if (!$this->_currentWriteService || !isset($this->_writeableServices[$this->_currentWriteService]) || $forceSelect)
{
if ($this->_currentWriteService && isset($this->_writeableServices[$this->_currentWriteService]) && $forceSelect)
{
// we probably had a communication error, ping the current read service, remove it if it times out
if ($this->_writeableServices[$this->_currentWriteService]->ping($this->_writePingTimeout) === false)
{
$this->removeWriteService($this->_currentWriteService);
}
}
if (count($this->_writeableServices))
{
// select one of the read services at random
$ids = array_keys($this->_writeableServices);
$id = $ids[rand(0, count($ids) - 1)];
$service = $this->_writeableServices[$id];
if (is_array($service))
{
//convert the array definition to a client object
$service = new Apache_Solr_Service($service['host'], $service['port'], $service['path']);
$this->_writeableServices[$id] = $service;
}
$this->_currentWriteService = $id;
}
else
{
throw new Apache_Solr_NoServiceAvailableException('No write services were available');
}
}
return $this->_writeableServices[$this->_currentWriteService];
}
/**
* Iterate through available write services and select the first with a ping
* that satisfies configured timeout restrictions (or the default). The
* timeout period will increase until a connection is made or the limit is
* reached. This will allow for increased reliability with heavily loaded
* server(s).
*
* @return Apache_Solr_Service
*
* @throws Apache_Solr_NoServiceAvailableException If there are no write services that meet requirements
*/
protected function _selectWriteServiceSafe($forceSelect = false)
{
if (!$this->_currentWriteService || !isset($this->_writeableServices[$this->_currentWriteService]) || $forceSelect)
{
if (count($this->_writeableServices))
{
$backoff = $this->_defaultBackoff;
do {
// select one of the read services at random
$ids = array_keys($this->_writeableServices);
$id = $ids[rand(0, count($ids) - 1)];
$service = $this->_writeableServices[$id];
if (is_array($service))
{
//convert the array definition to a client object
$service = new Apache_Solr_Service($service['host'], $service['port'], $service['path']);
$this->_writeableServices[$id] = $service;
}
$this->_currentWriteService = $id;
$backoff *= $this->_backoffEscalation;
if($backoff > $this->_backoffLimit)
{
throw new Apache_Solr_NoServiceAvailableException('No write services were available. All timeouts exceeded.');
}
} while($this->_writeableServices[$this->_currentWriteService]->ping($backoff) === false);
}
else
{
throw new Apache_Solr_NoServiceAvailableException('No write services were available');
}
}
return $this->_writeableServices[$this->_currentWriteService];
}
/**
* Set the create documents flag. This determines whether {@link Apache_Solr_Response} objects will
* parse the response and create {@link Apache_Solr_Document} instances in place.
*
* @param boolean $createDocuments
*/
public function setCreateDocuments($createDocuments)
{
$this->_createDocuments = (bool) $createDocuments;
// set on current read service
if ($this->_currentReadService)
{
$service = $this->_selectReadService();
$service->setCreateDocuments($createDocuments);
}
}
/**
* Get the current state of teh create documents flag.
*
* @return boolean
*/
public function getCreateDocuments()
{
return $this->_createDocuments;
}
/**
* Raw Add Method. Takes a raw post body and sends it to the update service. Post body
* should be a complete and well formed "add" xml document.
*
* @param string $rawPost
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function add($rawPost)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->add($rawPost);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Add a Solr Document to the index
*
* @param Apache_Solr_Document $document
* @param boolean $allowDups
* @param boolean $overwritePending
* @param boolean $overwriteCommitted
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function addDocument(Apache_Solr_Document $document, $allowDups = false, $overwritePending = true, $overwriteCommitted = true)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->addDocument($document, $allowDups, $overwritePending, $overwriteCommitted);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Add an array of Solr Documents to the index all at once
*
* @param array $documents Should be an array of Apache_Solr_Document instances
* @param boolean $allowDups
* @param boolean $overwritePending
* @param boolean $overwriteCommitted
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function addDocuments($documents, $allowDups = false, $overwritePending = true, $overwriteCommitted = true)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->addDocuments($documents, $allowDups, $overwritePending, $overwriteCommitted);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Send a commit command. Will be synchronous unless both wait parameters are set
* to false.
*
* @param boolean $waitFlush
* @param boolean $waitSearcher
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function commit($optimize = true, $waitFlush = true, $waitSearcher = true, $timeout = 3600)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->commit($optimize, $waitFlush, $waitSearcher, $timeout);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Raw Delete Method. Takes a raw post body and sends it to the update service. Body should be
* a complete and well formed "delete" xml document
*
* @param string $rawPost
* @param float $timeout Maximum expected duration of the delete operation on the server (otherwise, will throw a communication exception)
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function delete($rawPost, $timeout = 3600)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->delete($rawPost, $timeout);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Create a delete document based on document ID
*
* @param string $id
* @param boolean $fromPending
* @param boolean $fromCommitted
* @param float $timeout Maximum expected duration of the delete operation on the server (otherwise, will throw a communication exception)
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function deleteById($id, $fromPending = true, $fromCommitted = true, $timeout = 3600)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->deleteById($id, $fromPending, $fromCommitted, $timeout);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Create and post a delete document based on multiple document IDs.
*
* @param array $ids Expected to be utf-8 encoded strings
* @param boolean $fromPending
* @param boolean $fromCommitted
* @param float $timeout Maximum expected duration of the delete operation on the server (otherwise, will throw a communication exception)
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function deleteByMultipleIds($ids, $fromPending = true, $fromCommitted = true, $timeout = 3600)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->deleteByMultipleId($ids, $fromPending, $fromCommitted, $timeout);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Create a delete document based on a query and submit it
*
* @param string $rawQuery
* @param boolean $fromPending
* @param boolean $fromCommitted
* @param float $timeout Maximum expected duration of the delete operation on the server (otherwise, will throw a communication exception)
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function deleteByQuery($rawQuery, $fromPending = true, $fromCommitted = true, $timeout = 3600)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->deleteByQuery($rawQuery, $fromPending, $fromCommitted, $timeout);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Use Solr Cell to extract document contents. See {@link http://wiki.apache.org/solr/ExtractingRequestHandler} for information on how
* to use Solr Cell and what parameters are available.
*
* NOTE: when passing an Apache_Solr_Document instance, field names and boosts will automatically be prepended by "literal." and "boost."
* as appropriate. Any keys from the $params array will NOT be treated this way. Any mappings from the document will overwrite key / value
* pairs in the params array if they have the same name (e.g. you pass a "literal.id" key and value in your $params array but you also
* pass in a document isntance with an "id" field" - the document's value(s) will take precedence).
*
* @param string $file Path to file to extract data from
* @param array $params optional array of key value pairs that will be sent with the post (see Solr Cell documentation)
* @param Apache_Solr_Document $document optional document that will be used to generate post parameters (literal.* and boost.* params)
* @param string $mimetype optional mimetype specification (for the file being extracted)
*
* @return Apache_Solr_Response
*
* @throws Apache_Solr_InvalidArgumentException if $file, $params, or $document are invalid.
*/
public function extract($file, $params = array(), $document = null, $mimetype = 'application/octet-stream')
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->extract($file, $params, $document, $mimetype);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Use Solr Cell to extract document contents. See {@link http://wiki.apache.org/solr/ExtractingRequestHandler} for information on how
* to use Solr Cell and what parameters are available.
*
* NOTE: when passing an Apache_Solr_Document instance, field names and boosts will automatically be prepended by "literal." and "boost."
* as appropriate. Any keys from the $params array will NOT be treated this way. Any mappings from the document will overwrite key / value
* pairs in the params array if they have the same name (e.g. you pass a "literal.id" key and value in your $params array but you also
* pass in a document isntance with an "id" field" - the document's value(s) will take precedence).
*
* @param string $data Data that will be passed to Solr Cell
* @param array $params optional array of key value pairs that will be sent with the post (see Solr Cell documentation)
* @param Apache_Solr_Document $document optional document that will be used to generate post parameters (literal.* and boost.* params)
* @param string $mimetype optional mimetype specification (for the file being extracted)
*
* @return Apache_Solr_Response
*
* @throws Apache_Solr_InvalidArgumentException if $file, $params, or $document are invalid.
*
* @todo Should be using multipart/form-data to post parameter values, but I could not get my implementation to work. Needs revisisted.
*/
public function extractFromString($data, $params = array(), $document = null, $mimetype = 'application/octet-stream')
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->extractFromString($data, $params, $document, $mimetype);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Send an optimize command. Will be synchronous unless both wait parameters are set
* to false.
*
* @param boolean $waitFlush
* @param boolean $waitSearcher
* @param float $timeout Maximum expected duration of the optimize operation on the server (otherwise, will throw a communication exception)
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function optimize($waitFlush = true, $waitSearcher = true, $timeout = 3600)
{
$service = $this->_selectWriteService();
do
{
try
{
return $service->optimize($waitFlush, $waitSearcher, $timeout);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectWriteService(true);
} while ($service);
return false;
}
/**
* Simple Search interface
*
* @param string $query The raw query string
* @param int $offset The starting offset for result documents
* @param int $limit The maximum number of result documents to return
* @param array $params key / value pairs for query parameters, use arrays for multivalued parameters
* @param string $method The HTTP method (Apache_Solr_Service::METHOD_GET or Apache_Solr_Service::METHOD::POST)
* @return Apache_Solr_Response
*
* @throws Apache_Solr_HttpTransportException If an error occurs during the service call
*/
public function search($query, $offset = 0, $limit = 10, $params = array(), $method = Apache_Solr_Service::METHOD_GET)
{
$service = $this->_selectReadService();
do
{
try
{
return $service->search($query, $offset, $limit, $params, $method);
}
catch (Apache_Solr_HttpTransportException $e)
{
if ($e->getCode() != 0) //IF NOT COMMUNICATION ERROR
{
throw $e;
}
}
$service = $this->_selectReadService(true);
} while ($service);
return false;
}
}

Documentation generated on Wed, 04 May 2011 11:01:10 -0400 by phpDocumentor 1.4.3

Source for file Balancer.php