MultiExec::assertClient() - Code Metrics - Inspection of "First commit of redis cache utilising predis" - elkarte/Elkarte - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — development (#3708)

by Martyn

created 2023-05-12 19:19 UTC

MultiExec::assertClient() A

↳ Parent: MultiExec

Complexity

Conditions	3
Paths	3

Size

Total Lines	11
Code Lines	6

Duplication

Lines	0
Ratio	0 %

Importance

Changes	1
Bugs	0	Features	0

Metric	Value
cc	3
eloc	6
c	1
b	0
f	0
nc	3
nop	1
dl	0
loc	11
rs	10

<?php

/*
 * This file is part of the Predis package.
 *
 * (c) 2009-2020 Daniele Alessandri
 * (c) 2021-2023 Till Krüss
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Predis\Transaction;

use Exception;
use InvalidArgumentException;
use Predis\ClientContextInterface;
use Predis\ClientException;
use Predis\ClientInterface;
use Predis\Command\CommandInterface;
use Predis\CommunicationException;
use Predis\Connection\Cluster\ClusterInterface;
use Predis\NotSupportedException;
use Predis\Protocol\ProtocolException;
use Predis\Response\ErrorInterface as ErrorResponseInterface;
use Predis\Response\ServerException;
use Predis\Response\Status as StatusResponse;
use SplQueue;

/**
 * Client-side abstraction of a Redis transaction based on MULTI / EXEC.
 *
 * {@inheritdoc}
 */
class MultiExec implements ClientContextInterface
{
    private $state;

    protected $client;
    protected $commands;
    protected $exceptions = true;
    protected $attempts = 0;
    protected $watchKeys = [];
    protected $modeCAS = false;

    /**
     * @param ClientInterface $client  Client instance used by the transaction.
     * @param array           $options Initialization options.
     */
    public function __construct(ClientInterface $client, array $options = null)
    {
        $this->assertClient($client);

        $this->client = $client;
        $this->state = new MultiExecState();

        $this->configure($client, $options ?: []);
        $this->reset();
    }

    /**
     * Checks if the passed client instance satisfies the required conditions
     * needed to initialize the transaction object.
     *
     * @param ClientInterface $client Client instance used by the transaction object.
     *
     * @throws NotSupportedException
     */
    private function assertClient(ClientInterface $client)
    {
        if ($client->getConnection() instanceof ClusterInterface) {
            throw new NotSupportedException(
                'Cannot initialize a MULTI/EXEC transaction over cluster connections.'
            );
        }

        if (!$client->getCommandFactory()->supports('MULTI', 'EXEC', 'DISCARD')) {
            throw new NotSupportedException(
                'MULTI, EXEC and DISCARD are not supported by the current command factory.'
            );
        }
    }

    /**
     * Configures the transaction using the provided options.
     *
     * @param ClientInterface $client  Underlying client instance.
     * @param array           $options Array of options for the transaction.
     **/
    protected function configure(ClientInterface $client, array $options)
    {
        if (isset($options['exceptions'])) {
            $this->exceptions = (bool) $options['exceptions'];
        } else {
            $this->exceptions = $client->getOptions()->exceptions;
        }

        if (isset($options['cas'])) {
            $this->modeCAS = (bool) $options['cas'];
        }

        if (isset($options['watch']) && $keys = $options['watch']) {
            $this->watchKeys = $keys;
        }

        if (isset($options['retry'])) {
            $this->attempts = (int) $options['retry'];
        }
    }

    /**
     * Resets the state of the transaction.
     */
    protected function reset()
    {
        $this->state->reset();
        $this->commands = new SplQueue();
    }

    /**
     * Initializes the transaction context.
     */
    protected function initialize()
    {
        if ($this->state->isInitialized()) {
            return;
        }

        if ($this->modeCAS) {
            $this->state->flag(MultiExecState::CAS);
        }

        if ($this->watchKeys) {

            $this->watch($this->watchKeys);
        }

        $cas = $this->state->isCAS();
        $discarded = $this->state->isDiscarded();

        if (!$cas || ($cas && $discarded)) {
            $this->call('MULTI');

            if ($discarded) {
                $this->state->unflag(MultiExecState::CAS);
            }
        }

        $this->state->unflag(MultiExecState::DISCARDED);
        $this->state->flag(MultiExecState::INITIALIZED);
    }

    /**
     * Dynamically invokes a Redis command with the specified arguments.
     *
     * @param string $method    Command ID.
     * @param array  $arguments Arguments for the command.
     *
     * @return mixed
     */
    public function __call($method, $arguments)
    {
        return $this->executeCommand(
            $this->client->createCommand($method, $arguments)
        );
    }

    /**
     * Executes a Redis command bypassing the transaction logic.
     *
     * @param string $commandID Command ID.
     * @param array  $arguments Arguments for the command.
     *
     * @return mixed
     * @throws ServerException
     */
    protected function call($commandID, array $arguments = [])
    {
        $response = $this->client->executeCommand(
            $this->client->createCommand($commandID, $arguments)
        );

        if ($response instanceof ErrorResponseInterface) {
            throw new ServerException($response->getMessage());
        }

        return $response;
    }

    /**
     * Executes the specified Redis command.
     *
     * @param CommandInterface $command Command instance.
     *
     * @return $this|mixed
     * @throws AbortedMultiExecException
     * @throws CommunicationException
     */
    public function executeCommand(CommandInterface $command)
    {
        $this->initialize();

        if ($this->state->isCAS()) {
            return $this->client->executeCommand($command);
        }

        $response = $this->client->getConnection()->executeCommand($command);

        if ($response instanceof StatusResponse && $response == 'QUEUED') {

            $this->commands->enqueue($command);
        } elseif ($response instanceof ErrorResponseInterface) {
            throw new AbortedMultiExecException($this, $response->getMessage());
        } else {
            $this->onProtocolError('The server did not return a +QUEUED status response.');
        }

        return $this;
    }

    /**
     * Executes WATCH against one or more keys.
     *
     * @param string|array $keys One or more keys.
     *
     * @return mixed
     * @throws NotSupportedException
     * @throws ClientException
     */
    public function watch($keys)
    {
        if (!$this->client->getCommandFactory()->supports('WATCH')) {
            throw new NotSupportedException('WATCH is not supported by the current command factory.');
        }

        if ($this->state->isWatchAllowed()) {
            throw new ClientException('Sending WATCH after MULTI is not allowed.');
        }

        $response = $this->call('WATCH', is_array($keys) ? $keys : [$keys]);
        $this->state->flag(MultiExecState::WATCH);

        return $response;
    }

    /**
     * Finalizes the transaction by executing MULTI on the server.
     *
     * @return MultiExec
     */
    public function multi()
    {
        if ($this->state->check(MultiExecState::INITIALIZED | MultiExecState::CAS)) {
            $this->state->unflag(MultiExecState::CAS);
            $this->call('MULTI');
        } else {
            $this->initialize();
        }

        return $this;
    }

    /**
     * Executes UNWATCH.
     *
     * @return MultiExec
     * @throws NotSupportedException
     */
    public function unwatch()
    {
        if (!$this->client->getCommandFactory()->supports('UNWATCH')) {
            throw new NotSupportedException(
                'UNWATCH is not supported by the current command factory.'
            );
        }

        $this->state->unflag(MultiExecState::WATCH);
        $this->__call('UNWATCH', []);

        return $this;
    }

    /**
     * Resets the transaction by UNWATCH-ing the keys that are being WATCHed and
     * DISCARD-ing pending commands that have been already sent to the server.
     *
     * @return MultiExec
     */
    public function discard()
    {
        if ($this->state->isInitialized()) {
            $this->call($this->state->isCAS() ? 'UNWATCH' : 'DISCARD');

            $this->reset();
            $this->state->flag(MultiExecState::DISCARDED);
        }

        return $this;
    }

    /**
     * Executes the whole transaction.
     *
     * @return mixed
     */
    public function exec()
    {
        return $this->execute();
    }

    /**
     * Checks the state of the transaction before execution.
     *
     * @param mixed $callable Callback for execution.
     *
     * @throws InvalidArgumentException
     * @throws ClientException
     */
    private function checkBeforeExecution($callable)
    {
        if ($this->state->isExecuting()) {
            throw new ClientException(
                'Cannot invoke "execute" or "exec" inside an active transaction context.'
            );
        }

        if ($callable) {
            if (!is_callable($callable)) {
                throw new InvalidArgumentException('The argument must be a callable object.');
            }

            if (!$this->commands->isEmpty()) {
                $this->discard();

                throw new ClientException(
                    'Cannot execute a transaction block after using fluent interface.'
                );
            }
        } elseif ($this->attempts) {
            $this->discard();

            throw new ClientException(
                'Automatic retries are supported only when a callable block is provided.'
            );
        }
    }

    /**
     * Handles the actual execution of the whole transaction.
     *
     * @param mixed $callable Optional callback for execution.
     *
     * @return array
     * @throws CommunicationException
     * @throws AbortedMultiExecException
     * @throws ServerException
     */
    public function execute($callable = null)
    {
        $this->checkBeforeExecution($callable);

        $execResponse = null;

        $attempts = $this->attempts;

        do {
            if ($callable) {
                $this->executeTransactionBlock($callable);
            }

            if ($this->commands->isEmpty()) {
                if ($this->state->isWatching()) {
                    $this->discard();
                }

                return;
            }

            $execResponse = $this->call('EXEC');

            if ($execResponse === null) {
                if ($attempts === 0) {
                    throw new AbortedMultiExecException(
                        $this, 'The current transaction has been aborted by the server.'
                    );
                }

                $this->reset();

                continue;
            }

            break;
        } while ($attempts-- > 0);

        $response = [];
        $commands = $this->commands;
        $size = count($execResponse);

        if ($size !== count($commands)) {
            $this->onProtocolError('EXEC returned an unexpected number of response items.');
        }

        for ($i = 0; $i < $size; ++$i) {
            $cmdResponse = $execResponse[$i];

            if ($cmdResponse instanceof ErrorResponseInterface && $this->exceptions) {
                throw new ServerException($cmdResponse->getMessage());
            }

            $response[$i] = $commands->dequeue()->parseResponse($cmdResponse);
        }

        return $response;
    }

    /**
     * Passes the current transaction object to a callable block for execution.
     *
     * @param mixed $callable Callback.
     *
     * @throws CommunicationException
     * @throws ServerException
     */
    protected function executeTransactionBlock($callable)
    {
        $exception = null;
        $this->state->flag(MultiExecState::INSIDEBLOCK);

        try {
            call_user_func($callable, $this);
        } catch (CommunicationException $exception) {
            // NOOP
        } catch (ServerException $exception) {
            // NOOP
        } catch (Exception $exception) {
            $this->discard();
        }

        $this->state->unflag(MultiExecState::INSIDEBLOCK);

        if ($exception) {
            throw $exception;
        }
    }

    /**
     * Helper method for protocol errors encountered inside the transaction.
     *
     * @param string $message Error message.
     */
    private function onProtocolError($message)
    {
        // Since a MULTI/EXEC block cannot be initialized when using aggregate
        // connections we can safely assume that Predis\Client::getConnection()
        // will return a Predis\Connection\NodeConnectionInterface instance.
        CommunicationException::handle(new ProtocolException(
            $this->client->getConnection(), $message
        ));
    }
}


1			<?php
2
3			/*
4			* This file is part of the Predis package.
5			*
6			* (c) 2009-2020 Daniele Alessandri
7			* (c) 2021-2023 Till Krüss
8			*
9			* For the full copyright and license information, please view the LICENSE
10			* file that was distributed with this source code.
11			*/
12
13			namespace Predis\Transaction;
14
15			use Exception;
16			use InvalidArgumentException;
17			use Predis\ClientContextInterface;
18			use Predis\ClientException;
19			use Predis\ClientInterface;
20			use Predis\Command\CommandInterface;
21			use Predis\CommunicationException;
22			use Predis\Connection\Cluster\ClusterInterface;
23			use Predis\NotSupportedException;
24			use Predis\Protocol\ProtocolException;
25			use Predis\Response\ErrorInterface as ErrorResponseInterface;
26			use Predis\Response\ServerException;
27			use Predis\Response\Status as StatusResponse;
28			use SplQueue;
29
30			/**
31			* Client-side abstraction of a Redis transaction based on MULTI / EXEC.
32			*
33			* {@inheritdoc}
34			*/
35			class MultiExec implements ClientContextInterface
36			{
37			private $state;
38
39			protected $client;
40			protected $commands;
41			protected $exceptions = true;
42			protected $attempts = 0;
43			protected $watchKeys = [];
44			protected $modeCAS = false;
45
46			/**
47			* @param ClientInterface $client Client instance used by the transaction.
48			* @param array $options Initialization options.
49			*/
50			public function __construct(ClientInterface $client, array $options = null)
51			{
52			$this->assertClient($client);
53
54			$this->client = $client;
55			$this->state = new MultiExecState();
56
57			$this->configure($client, $options ?: []);
58			$this->reset();
59			}
60
61			/**
62			* Checks if the passed client instance satisfies the required conditions
63			* needed to initialize the transaction object.
64			*
65			* @param ClientInterface $client Client instance used by the transaction object.
66			*
67			* @throws NotSupportedException
68			*/
69			private function assertClient(ClientInterface $client)
70			{
71			if ($client->getConnection() instanceof ClusterInterface) {
72			throw new NotSupportedException(
73			'Cannot initialize a MULTI/EXEC transaction over cluster connections.'
74			);
75			}
76
77			if (!$client->getCommandFactory()->supports('MULTI', 'EXEC', 'DISCARD')) {
78			throw new NotSupportedException(
79			'MULTI, EXEC and DISCARD are not supported by the current command factory.'
80			);
81			}
82			}
83
84			/**
85			* Configures the transaction using the provided options.
86			*
87			* @param ClientInterface $client Underlying client instance.
88			* @param array $options Array of options for the transaction.
89			**/
90			protected function configure(ClientInterface $client, array $options)
91			{
92			if (isset($options['exceptions'])) {
93			$this->exceptions = (bool) $options['exceptions'];
94			} else {
95			$this->exceptions = $client->getOptions()->exceptions;
96			}
97
98			if (isset($options['cas'])) {
99			$this->modeCAS = (bool) $options['cas'];
100			}
101
102			if (isset($options['watch']) && $keys = $options['watch']) {
103			$this->watchKeys = $keys;
104			}
105
106			if (isset($options['retry'])) {
107			$this->attempts = (int) $options['retry'];
108			}
109			}
110
111			/**
112			* Resets the state of the transaction.
113			*/
114			protected function reset()
115			{
116			$this->state->reset();
117			$this->commands = new SplQueue();
118			}
119
120			/**
121			* Initializes the transaction context.
122			*/
123			protected function initialize()
124			{
125			if ($this->state->isInitialized()) {
126			return;
127			}
128
129			if ($this->modeCAS) {
130			$this->state->flag(MultiExecState::CAS);
131			}
132
133			if ($this->watchKeys) {
			0 ignored issues – show Bug Best Practice introduced 2023-04-10 20:18 UTC by Report Bug Copy Issue Report The expression `$this->watchKeys` of type `array` is implicitly converted to a boolean; are you sure this is intended? If so, consider using `! empty($expr)` instead to make it clear that you intend to check for an array without elements. This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent. Consider making the comparison explicit by using `empty(..)` or `! empty(...)` instead. Loading history...
134			$this->watch($this->watchKeys);
135			}
136
137			$cas = $this->state->isCAS();
138			$discarded = $this->state->isDiscarded();
139
140			if (!$cas \|\| ($cas && $discarded)) {
141			$this->call('MULTI');
142
143			if ($discarded) {
144			$this->state->unflag(MultiExecState::CAS);
145			}
146			}
147
148			$this->state->unflag(MultiExecState::DISCARDED);
149			$this->state->flag(MultiExecState::INITIALIZED);
150			}
151
152			/**
153			* Dynamically invokes a Redis command with the specified arguments.
154			*
155			* @param string $method Command ID.
156			* @param array $arguments Arguments for the command.
157			*
158			* @return mixed
159			*/
160			public function __call($method, $arguments)
161			{
162			return $this->executeCommand(
163			$this->client->createCommand($method, $arguments)
164			);
165			}
166
167			/**
168			* Executes a Redis command bypassing the transaction logic.
169			*
170			* @param string $commandID Command ID.
171			* @param array $arguments Arguments for the command.
172			*
173			* @return mixed
174			* @throws ServerException
175			*/
176			protected function call($commandID, array $arguments = [])
177			{
178			$response = $this->client->executeCommand(
179			$this->client->createCommand($commandID, $arguments)
180			);
181
182			if ($response instanceof ErrorResponseInterface) {
183			throw new ServerException($response->getMessage());
184			}
185
186			return $response;
187			}
188
189			/**
190			* Executes the specified Redis command.
191			*
192			* @param CommandInterface $command Command instance.
193			*
194			* @return $this\|mixed
195			* @throws AbortedMultiExecException
196			* @throws CommunicationException
197			*/
198			public function executeCommand(CommandInterface $command)
199			{
200			$this->initialize();
201
202			if ($this->state->isCAS()) {
203			return $this->client->executeCommand($command);
204			}
205
206			$response = $this->client->getConnection()->executeCommand($command);
207
208			if ($response instanceof StatusResponse && $response == 'QUEUED') {
			0 ignored issues – show introduced 2023-04-10 20:18 UTC by Report Bug Copy Issue Report The condition `$response == 'QUEUED'` is always `false`. Loading history...
209			$this->commands->enqueue($command);
210			} elseif ($response instanceof ErrorResponseInterface) {
211			throw new AbortedMultiExecException($this, $response->getMessage());
212			} else {
213			$this->onProtocolError('The server did not return a +QUEUED status response.');
214			}
215
216			return $this;
217			}
218
219			/**
220			* Executes WATCH against one or more keys.
221			*
222			* @param string\|array $keys One or more keys.
223			*
224			* @return mixed
225			* @throws NotSupportedException
226			* @throws ClientException
227			*/
228			public function watch($keys)
229			{
230			if (!$this->client->getCommandFactory()->supports('WATCH')) {
231			throw new NotSupportedException('WATCH is not supported by the current command factory.');
232			}
233
234			if ($this->state->isWatchAllowed()) {
235			throw new ClientException('Sending WATCH after MULTI is not allowed.');
236			}
237
238			$response = $this->call('WATCH', is_array($keys) ? $keys : [$keys]);
239			$this->state->flag(MultiExecState::WATCH);
240
241			return $response;
242			}
243
244			/**
245			* Finalizes the transaction by executing MULTI on the server.
246			*
247			* @return MultiExec
248			*/
249			public function multi()
250			{
251			if ($this->state->check(MultiExecState::INITIALIZED \| MultiExecState::CAS)) {
252			$this->state->unflag(MultiExecState::CAS);
253			$this->call('MULTI');
254			} else {
255			$this->initialize();
256			}
257
258			return $this;
259			}
260
261			/**
262			* Executes UNWATCH.
263			*
264			* @return MultiExec
265			* @throws NotSupportedException
266			*/
267			public function unwatch()
268			{
269			if (!$this->client->getCommandFactory()->supports('UNWATCH')) {
270			throw new NotSupportedException(
271			'UNWATCH is not supported by the current command factory.'
272			);
273			}
274
275			$this->state->unflag(MultiExecState::WATCH);
276			$this->__call('UNWATCH', []);
277
278			return $this;
279			}
280
281			/**
282			* Resets the transaction by UNWATCH-ing the keys that are being WATCHed and
283			* DISCARD-ing pending commands that have been already sent to the server.
284			*
285			* @return MultiExec
286			*/
287			public function discard()
288			{
289			if ($this->state->isInitialized()) {
290			$this->call($this->state->isCAS() ? 'UNWATCH' : 'DISCARD');
291
292			$this->reset();
293			$this->state->flag(MultiExecState::DISCARDED);
294			}
295
296			return $this;
297			}
298
299			/**
300			* Executes the whole transaction.
301			*
302			* @return mixed
303			*/
304			public function exec()
305			{
306			return $this->execute();
307			}
308
309			/**
310			* Checks the state of the transaction before execution.
311			*
312			* @param mixed $callable Callback for execution.
313			*
314			* @throws InvalidArgumentException
315			* @throws ClientException
316			*/
317			private function checkBeforeExecution($callable)
318			{
319			if ($this->state->isExecuting()) {
320			throw new ClientException(
321			'Cannot invoke "execute" or "exec" inside an active transaction context.'
322			);
323			}
324
325			if ($callable) {
326			if (!is_callable($callable)) {
327			throw new InvalidArgumentException('The argument must be a callable object.');
328			}
329
330			if (!$this->commands->isEmpty()) {
331			$this->discard();
332
333			throw new ClientException(
334			'Cannot execute a transaction block after using fluent interface.'
335			);
336			}
337			} elseif ($this->attempts) {
338			$this->discard();
339
340			throw new ClientException(
341			'Automatic retries are supported only when a callable block is provided.'
342			);
343			}
344			}
345
346			/**
347			* Handles the actual execution of the whole transaction.
348			*
349			* @param mixed $callable Optional callback for execution.
350			*
351			* @return array
352			* @throws CommunicationException
353			* @throws AbortedMultiExecException
354			* @throws ServerException
355			*/
356			public function execute($callable = null)
357			{
358			$this->checkBeforeExecution($callable);
359
360			$execResponse = null;
			0 ignored issues – show Unused Code introduced 2023-04-10 20:18 UTC by Report Bug Copy Issue Report The assignment to `$execResponse` is dead and can be removed. Loading history...
361			$attempts = $this->attempts;
362
363			do {
364			if ($callable) {
365			$this->executeTransactionBlock($callable);
366			}
367
368			if ($this->commands->isEmpty()) {
369			if ($this->state->isWatching()) {
370			$this->discard();
371			}
372
373			return;
374			}
375
376			$execResponse = $this->call('EXEC');
377
378			if ($execResponse === null) {
379			if ($attempts === 0) {
380			throw new AbortedMultiExecException(
381			$this, 'The current transaction has been aborted by the server.'
382			);
383			}
384
385			$this->reset();
386
387			continue;
388			}
389
390			break;
391			} while ($attempts-- > 0);
392
393			$response = [];
394			$commands = $this->commands;
395			$size = count($execResponse);
396
397			if ($size !== count($commands)) {
398			$this->onProtocolError('EXEC returned an unexpected number of response items.');
399			}
400
401			for ($i = 0; $i < $size; ++$i) {
402			$cmdResponse = $execResponse[$i];
403
404			if ($cmdResponse instanceof ErrorResponseInterface && $this->exceptions) {
405			throw new ServerException($cmdResponse->getMessage());
406			}
407
408			$response[$i] = $commands->dequeue()->parseResponse($cmdResponse);
409			}
410
411			return $response;
412			}
413
414			/**
415			* Passes the current transaction object to a callable block for execution.
416			*
417			* @param mixed $callable Callback.
418			*
419			* @throws CommunicationException
420			* @throws ServerException
421			*/
422			protected function executeTransactionBlock($callable)
423			{
424			$exception = null;
425			$this->state->flag(MultiExecState::INSIDEBLOCK);
426
427			try {
428			call_user_func($callable, $this);
429			} catch (CommunicationException $exception) {
430			// NOOP
431			} catch (ServerException $exception) {
432			// NOOP
433			} catch (Exception $exception) {
434			$this->discard();
435			}
436
437			$this->state->unflag(MultiExecState::INSIDEBLOCK);
438
439			if ($exception) {
440			throw $exception;
441			}
442			}
443
444			/**
445			* Helper method for protocol errors encountered inside the transaction.
446			*
447			* @param string $message Error message.
448			*/
449			private function onProtocolError($message)
450			{
451			// Since a MULTI/EXEC block cannot be initialized when using aggregate
452			// connections we can safely assume that Predis\Client::getConnection()
453			// will return a Predis\Connection\NodeConnectionInterface instance.
454			CommunicationException::handle(new ProtocolException(
455			$this->client->getConnection(), $message
456			));
457			}
458			}
459

elkarte / Elkarte

Pull Request — development (#3708)

MultiExec::assertClient() A

Complexity

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Duplication

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