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RedisConnRef.php
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1 <?php
20 use Psr\Log\LoggerAwareInterface;
21 use Psr\Log\LoggerInterface;
22 
31 class RedisConnRef implements LoggerAwareInterface {
33  protected $pool;
35  protected $conn;
37  protected $server;
39  protected $lastError;
40 
44  protected $logger;
45 
49  private const AUTH_NO_ERROR = 200;
50 
54  private const AUTH_ERROR_TEMPORARY = 201;
55 
59  private const AUTH_ERROR_PERMANENT = 202;
60 
67  public function __construct(
68  RedisConnectionPool $pool, $server, Redis $conn, LoggerInterface $logger
69  ) {
70  $this->pool = $pool;
71  $this->server = $server;
72  $this->conn = $conn;
73  $this->logger = $logger;
74  }
75 
76  public function setLogger( LoggerInterface $logger ) {
77  $this->logger = $logger;
78  }
79 
84  public function getServer() {
85  return $this->server;
86  }
87 
88  public function getLastError() {
89  return $this->lastError;
90  }
91 
92  public function clearLastError() {
93  $this->lastError = null;
94  }
95 
104  public function __call( $name, $arguments ) {
105  // Work around https://github.com/nicolasff/phpredis/issues/70
106  $lname = strtolower( $name );
107  if (
108  ( $lname === 'blpop' || $lname === 'brpop' || $lname === 'brpoplpush' )
109  && count( $arguments ) > 1
110  ) {
111  // Get timeout off the end since it is always required and argument length can vary
112  $timeout = end( $arguments );
113  // Only give the additional one second buffer if not requesting an infinite timeout
114  $this->pool->resetTimeout( $this->conn, ( $timeout > 0 ? $timeout + 1 : $timeout ) );
115  }
116 
117  return $this->tryCall( $name, $arguments );
118  }
119 
128  private function tryCall( $method, $arguments ) {
129  $this->conn->clearLastError();
130  try {
131  $res = $this->conn->$method( ...$arguments );
132  $authError = $this->checkAuthentication();
133  if ( $authError === self::AUTH_ERROR_TEMPORARY ) {
134  $res = $this->conn->$method( ...$arguments );
135  }
136  if ( $authError === self::AUTH_ERROR_PERMANENT ) {
137  throw new RedisException( "Failure reauthenticating to Redis." );
138  }
139  return $res;
140  } finally {
141  $this->postCallCleanup();
142  }
143  }
144 
155  public function scan( &$iterator, $pattern = null, $count = null ) {
156  return $this->tryCall( 'scan', [ &$iterator, $pattern, $count ] );
157  }
158 
170  public function sScan( $key, &$iterator, $pattern = null, $count = null ) {
171  return $this->tryCall( 'sScan', [ $key, &$iterator, $pattern, $count ] );
172  }
173 
185  public function hScan( $key, &$iterator, $pattern = null, $count = null ) {
186  return $this->tryCall( 'hScan', [ $key, &$iterator, $pattern, $count ] );
187  }
188 
200  public function zScan( $key, &$iterator, $pattern = null, $count = null ) {
201  return $this->tryCall( 'zScan', [ $key, &$iterator, $pattern, $count ] );
202  }
203 
209  private function checkAuthentication() {
210  $lastError = $this->conn->getLastError();
211  if ( $lastError && preg_match( '/^ERR operation not permitted\b/', $lastError ) ) {
212  if ( !$this->pool->reauthenticateConnection( $this->server, $this->conn ) ) {
214  }
215  $this->conn->clearLastError();
216  $this->logger->info(
217  "Used automatic re-authentication for Redis.",
218  [ 'redis_server' => $this->server ]
219  );
221  }
222  return self::AUTH_NO_ERROR;
223  }
224 
230  private function postCallCleanup() {
231  $this->lastError = $this->conn->getLastError() ?: $this->lastError;
232 
233  // Restore original timeout in the case of blocking calls.
234  $this->pool->resetTimeout( $this->conn );
235  }
236 
244  public function luaEval( $script, array $params, $numKeys ) {
245  $sha1 = sha1( $script ); // 40 char hex
246  $conn = $this->conn; // convenience
247  $server = $this->server; // convenience
248 
249  // Try to run the server-side cached copy of the script
250  $conn->clearLastError();
251  $res = $conn->evalSha( $sha1, $params, $numKeys );
252  // If we got a permission error reply that means that (a) we are not in
253  // multi()/pipeline() and (b) some connection problem likely occurred. If
254  // the password the client gave was just wrong, an exception should have
255  // been thrown back in getConnection() previously.
256  $lastError = $conn->getLastError();
257  if ( $lastError && preg_match( '/^ERR operation not permitted\b/', $lastError ) ) {
258  $this->pool->reauthenticateConnection( $server, $conn );
259  $conn->clearLastError();
260  $res = $conn->eval( $script, $params, $numKeys );
261  $this->logger->info(
262  "Used automatic re-authentication for Lua script '$sha1'.",
263  [ 'redis_server' => $server ]
264  );
265  }
266  // If the script is not in cache, use eval() to retry and cache it
267  $lastError = $conn->getLastError();
268  if ( $lastError && preg_match( '/^NOSCRIPT/', $lastError ) ) {
269  $conn->clearLastError();
270  $res = $conn->eval( $script, $params, $numKeys );
271  $this->logger->info(
272  "Used eval() for Lua script '$sha1'.",
273  [ 'redis_server' => $server ]
274  );
275  }
276 
277  $lastError = $conn->getLastError();
278  if ( $lastError ) { // script bug?
279  $this->logger->error(
280  'Lua script error on server "{redis_server}": {lua_error}',
281  [
282  'redis_server' => $server,
283  'lua_error' => $lastError
284  ]
285  );
286  $this->lastError = $lastError;
287  }
288 
289  return $res;
290  }
291 
296  public function isConnIdentical( Redis $conn ) {
297  return $this->conn === $conn;
298  }
299 
300  public function __destruct() {
301  $this->pool->freeConnection( $this->server, $this->conn );
302  }
303 }
Helper class to handle automatically marking connections as reusable (via RAII pattern)
RedisConnectionPool $pool
LoggerInterface $logger
zScan( $key, &$iterator, $pattern=null, $count=null)
Sorted Set Scan Handle this explicitly due to needing the iterator passed by reference.
string $server
const AUTH_ERROR_PERMANENT
Authentication error was permanent and could not be recovered.
scan(&$iterator, $pattern=null, $count=null)
Key Scan Handle this explicitly due to needing the iterator passed by reference.
tryCall( $method, $arguments)
Do the method call in the common try catch handler.
__call( $name, $arguments)
Magic __call handler for most Redis functions.
luaEval( $script, array $params, $numKeys)
sScan( $key, &$iterator, $pattern=null, $count=null)
Set Scan Handle this explicitly due to needing the iterator passed by reference.
hScan( $key, &$iterator, $pattern=null, $count=null)
Hash Scan Handle this explicitly due to needing the iterator passed by reference.
string null $lastError
__construct(RedisConnectionPool $pool, $server, Redis $conn, LoggerInterface $logger)
setLogger(LoggerInterface $logger)
postCallCleanup()
Post Redis call cleanup.
checkAuthentication()
Handle authentication errors and automatically reauthenticate.
const AUTH_ERROR_TEMPORARY
Temporary authentication error; recovered by reauthenticating.
const AUTH_NO_ERROR
No authentication errors.
isConnIdentical(Redis $conn)
Helper class to manage Redis connections.