/src/Replication/ReplicationStrategy.php
PHP | 304 lines | 188 code | 28 blank | 88 comment | 22 complexity | dc7af4d5c9308a3ce390907c589bbba7 MD5 | raw file
- <?php
- /*
- * This file is part of the Predis package.
- *
- * (c) Daniele Alessandri <suppakilla@gmail.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
- namespace Predis\Replication;
- use Predis\Command\CommandInterface;
- use Predis\NotSupportedException;
- /**
- * Defines a strategy for master/slave replication.
- *
- * @author Daniele Alessandri <suppakilla@gmail.com>
- */
- class ReplicationStrategy
- {
- protected $disallowed;
- protected $readonly;
- protected $readonlySHA1;
- /**
- *
- */
- public function __construct()
- {
- $this->disallowed = $this->getDisallowedOperations();
- $this->readonly = $this->getReadOnlyOperations();
- $this->readonlySHA1 = array();
- }
- /**
- * Returns if the specified command will perform a read-only operation
- * on Redis or not.
- *
- * @param CommandInterface $command Command instance.
- *
- * @throws NotSupportedException
- *
- * @return bool
- */
- public function isReadOperation(CommandInterface $command)
- {
- if (isset($this->disallowed[$id = $command->getId()])) {
- throw new NotSupportedException(
- "The command '$id' is not allowed in replication mode."
- );
- }
- if (isset($this->readonly[$id])) {
- if (true === $readonly = $this->readonly[$id]) {
- return true;
- }
- return call_user_func($readonly, $command);
- }
- if (($eval = $id === 'EVAL') || $id === 'EVALSHA') {
- $sha1 = $eval ? sha1($command->getArgument(0)) : $command->getArgument(0);
- if (isset($this->readonlySHA1[$sha1])) {
- if (true === $readonly = $this->readonlySHA1[$sha1]) {
- return true;
- }
- return call_user_func($readonly, $command);
- }
- }
- return false;
- }
- /**
- * Returns if the specified command is not allowed for execution in a master
- * / slave replication context.
- *
- * @param CommandInterface $command Command instance.
- *
- * @return bool
- */
- public function isDisallowedOperation(CommandInterface $command)
- {
- return isset($this->disallowed[$command->getId()]);
- }
- /**
- * Checks if a SORT command is a readable operation by parsing the arguments
- * array of the specified commad instance.
- *
- * @param CommandInterface $command Command instance.
- *
- * @return bool
- */
- protected function isSortReadOnly(CommandInterface $command)
- {
- $arguments = $command->getArguments();
- $argc = count($arguments);
- if ($argc > 1) {
- for ($i = 1; $i < $argc; ++$i) {
- $argument = strtoupper($arguments[$i]);
- if ($argument === 'STORE') {
- return false;
- }
- }
- }
- return true;
- }
- /**
- * Checks if BITFIELD performs a read-only operation by looking for certain
- * SET and INCRYBY modifiers in the arguments array of the command.
- *
- * @param CommandInterface $command Command instance.
- *
- * @return bool
- */
- protected function isBitfieldReadOnly(CommandInterface $command)
- {
- $arguments = $command->getArguments();
- $argc = count($arguments);
- if ($argc >= 2) {
- for ($i = 1; $i < $argc; ++$i) {
- $argument = strtoupper($arguments[$i]);
- if ($argument === 'SET' || $argument === 'INCRBY') {
- return false;
- }
- }
- }
- return true;
- }
- /**
- * Checks if a GEORADIUS command is a readable operation by parsing the
- * arguments array of the specified commad instance.
- *
- * @param CommandInterface $command Command instance.
- *
- * @return bool
- */
- protected function isGeoradiusReadOnly(CommandInterface $command)
- {
- $arguments = $command->getArguments();
- $argc = count($arguments);
- $startIndex = $command->getId() === 'GEORADIUS' ? 5 : 4;
- if ($argc > $startIndex) {
- for ($i = $startIndex; $i < $argc; ++$i) {
- $argument = strtoupper($arguments[$i]);
- if ($argument === 'STORE' || $argument === 'STOREDIST') {
- return false;
- }
- }
- }
- return true;
- }
- /**
- * Marks a command as a read-only operation.
- *
- * When the behavior of a command can be decided only at runtime depending
- * on its arguments, a callable object can be provided to dynamically check
- * if the specified command performs a read or a write operation.
- *
- * @param string $commandID Command ID.
- * @param mixed $readonly A boolean value or a callable object.
- */
- public function setCommandReadOnly($commandID, $readonly = true)
- {
- $commandID = strtoupper($commandID);
- if ($readonly) {
- $this->readonly[$commandID] = $readonly;
- } else {
- unset($this->readonly[$commandID]);
- }
- }
- /**
- * Marks a Lua script for EVAL and EVALSHA as a read-only operation. When
- * the behaviour of a script can be decided only at runtime depending on
- * its arguments, a callable object can be provided to dynamically check
- * if the passed instance of EVAL or EVALSHA performs write operations or
- * not.
- *
- * @param string $script Body of the Lua script.
- * @param mixed $readonly A boolean value or a callable object.
- */
- public function setScriptReadOnly($script, $readonly = true)
- {
- $sha1 = sha1($script);
- if ($readonly) {
- $this->readonlySHA1[$sha1] = $readonly;
- } else {
- unset($this->readonlySHA1[$sha1]);
- }
- }
- /**
- * Returns the default list of disallowed commands.
- *
- * @return array
- */
- protected function getDisallowedOperations()
- {
- return array(
- 'SHUTDOWN' => true,
- 'INFO' => true,
- 'DBSIZE' => true,
- 'LASTSAVE' => true,
- 'CONFIG' => true,
- 'MONITOR' => true,
- 'SLAVEOF' => true,
- 'SAVE' => true,
- 'BGSAVE' => true,
- 'BGREWRITEAOF' => true,
- 'SLOWLOG' => true,
- );
- }
- /**
- * Returns the default list of commands performing read-only operations.
- *
- * @return array
- */
- protected function getReadOnlyOperations()
- {
- return array(
- 'EXISTS' => true,
- 'TYPE' => true,
- 'KEYS' => true,
- 'SCAN' => true,
- 'RANDOMKEY' => true,
- 'TTL' => true,
- 'GET' => true,
- 'MGET' => true,
- 'SUBSTR' => true,
- 'STRLEN' => true,
- 'GETRANGE' => true,
- 'GETBIT' => true,
- 'LLEN' => true,
- 'LRANGE' => true,
- 'LINDEX' => true,
- 'SCARD' => true,
- 'SISMEMBER' => true,
- 'SINTER' => true,
- 'SUNION' => true,
- 'SDIFF' => true,
- 'SMEMBERS' => true,
- 'SSCAN' => true,
- 'SRANDMEMBER' => true,
- 'ZRANGE' => true,
- 'ZREVRANGE' => true,
- 'ZRANGEBYSCORE' => true,
- 'ZREVRANGEBYSCORE' => true,
- 'ZCARD' => true,
- 'ZSCORE' => true,
- 'ZCOUNT' => true,
- 'ZRANK' => true,
- 'ZREVRANK' => true,
- 'ZSCAN' => true,
- 'ZLEXCOUNT' => true,
- 'ZRANGEBYLEX' => true,
- 'ZREVRANGEBYLEX' => true,
- 'HGET' => true,
- 'HMGET' => true,
- 'HEXISTS' => true,
- 'HLEN' => true,
- 'HKEYS' => true,
- 'HVALS' => true,
- 'HGETALL' => true,
- 'HSCAN' => true,
- 'HSTRLEN' => true,
- 'PING' => true,
- 'AUTH' => true,
- 'SELECT' => true,
- 'ECHO' => true,
- 'QUIT' => true,
- 'OBJECT' => true,
- 'BITCOUNT' => true,
- 'BITPOS' => true,
- 'TIME' => true,
- 'PFCOUNT' => true,
- 'SORT' => array($this, 'isSortReadOnly'),
- 'BITFIELD' => array($this, 'isBitfieldReadOnly'),
- 'GEOHASH' => true,
- 'GEOPOS' => true,
- 'GEODIST' => true,
- 'GEORADIUS' => array($this, 'isGeoradiusReadOnly'),
- 'GEORADIUSBYMEMBER' => array($this, 'isGeoradiusReadOnly'),
- );
- }
- }