Publish::composePubAckAnswer() - Code Metrics - Inspection of "Unifying control of blocking mechanism (Still WIP)" - unreal4u/mqtt - Measure and Improve Code Quality continuously with Scrutinizer

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Push — master ( 49fa37...dabd6a )

by Camilo

created 2018-01-17 23:52 UTC

Publish::composePubAckAnswer() A

↳ Parent: Publish

Complexity

Conditions	1
Paths	1

Size

Total Lines	5
Code Lines	3

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	0
CRAP Score	2

Importance

Changes

Metric	Value
dl	0
loc	5
ccs	0
cts	4
cp	0
rs	9.4285
c	0
b	0
f	0
cc	1
eloc	3
nc	1
nop	0
crap	2

<?php

declare(strict_types=1);

namespace unreal4u\MQTT\Protocol;

use unreal4u\MQTT\Application\EmptyReadableResponse;
use unreal4u\MQTT\Application\Message;
use unreal4u\MQTT\Exceptions\InvalidQoSLevel;
use unreal4u\MQTT\Internals\ClientInterface;
use unreal4u\MQTT\Internals\ProtocolBase;
use unreal4u\MQTT\Internals\ReadableContent;
use unreal4u\MQTT\Internals\ReadableContentInterface;
use unreal4u\MQTT\Internals\WritableContent;
use unreal4u\MQTT\Internals\WritableContentInterface;
use unreal4u\MQTT\Utilities;

/**
 * A PUBLISH Control Packet is sent from a Client to a Server or vice-versa to transport an Application Message.
 *
 * @see http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718037
 */
final class Publish extends ProtocolBase implements ReadableContentInterface, WritableContentInterface
{
    use ReadableContent;
    use WritableContent;

    const CONTROL_PACKET_VALUE = 3;

    /**
     * Contains the message to be sent
     * @var Message
     */
    private $message;

    /**
     * Some interchanges with the broker will send or receive a packet identifier
     * @var int
     */
    public $packetIdentifier = 0;

    /**
     * Flag to check whether a message is a redelivery (DUP flag)
     * @see http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718038
     * @var bool
     */
    public $isRedelivery = false;

    public function createVariableHeader(): string
    {
        if ($this->message === null) {
            throw new \InvalidArgumentException('You must at least provide a message object with a topic name');
        }

        $bitString = $this->createUTF8String($this->message->getTopicName());
        // Reset the special flags should the object be reused with another message
        $this->specialFlags = 0;

        if ($this->isRedelivery) {
            $this->logger->debug('Activating redelivery bit');
            // DUP flag: if the message is a re-delivery, mark it as such
            $this->specialFlags |= 8;
        }

        // Check QoS level and perform the corresponding actions
        if ($this->message->getQoSLevel() !== 0) {
            // 2 for QoS lvl1 and 4 for QoS lvl2
            $this->specialFlags |= ($this->message->getQoSLevel() * 2);
            $this->packetIdentifier++;
            $bitString .= Utilities::convertNumberToBinaryString($this->packetIdentifier);
            $this->logger->debug(sprintf('Activating QoS level %d bit', $this->message->getQoSLevel()), [
                'specialFlags' => $this->specialFlags,
            ]);
        }

        if ($this->message->isRetained()) {
            // RETAIN flag: should the server retain the message?
            $this->specialFlags |= 1;
            $this->logger->debug('Activating retain flag', ['specialFlags' => $this->specialFlags]);
        }

        $this->logger->info('Variable header created', ['specialFlags' => $this->specialFlags]);

        return $bitString;
    }

    public function createPayload(): string
    {
        if (!$this->message->validateMessage()) {
            throw new \InvalidArgumentException('Invalid message');
        }

        return $this->message->getPayload();
    }

    /**
     * QoS level 0 does not have to wait for a answer, so return false. Any other QoS level returns true
     * @return bool
     */
    public function shouldExpectAnswer(): bool
    {
        $shouldExpectAnswer = !($this->message->getQoSLevel() === 0);
        $this->logger->debug('Checking whether we should expect an answer or not', [
            'shouldExpectAnswer' => $shouldExpectAnswer,
        ]);
        return $shouldExpectAnswer;
    }

    public function expectAnswer(string $data, ClientInterface $client): ReadableContentInterface
    {
        if ($this->shouldExpectAnswer() === false) {
            return new EmptyReadableResponse($this->logger);
        }

        $pubAck = new PubAck($this->logger);
        $pubAck->instantiateObject($data, $client);
        return $pubAck;
    }

    /**
     * Sets the to be sent message
     *
     * @param Message $message
     * @return WritableContentInterface
     */
    public function setMessage(Message $message): WritableContentInterface
    {
        $this->message = $message;
        return $this;
    }

    /**
     * Gets the set message
     *
     * @return Message
     */
    public function getMessage(): Message
    {
        return $this->message;
    }

    /**
     * Sets several bits and pieces from the first byte of the fixed header for the Publish packet
     *
     * @param int $firstByte
     * @return Publish
     * @throws \unreal4u\MQTT\Exceptions\InvalidQoSLevel
     */
    private function analyzeFirstByte(int $firstByte): Publish
    {
        $this->logger->debug('Analyzing first byte', [sprintf('%08d', decbin($firstByte))]);
        // Retained bit is bit 0 of first byte
        $this->message->setRetainFlag(false);
        if ($firstByte & 1) {
            $this->message->setRetainFlag(true);
        }
        // QoS level are the last bits 2 & 1 of the first byte
        $this->message->setQoSLevel($this->determineIncomingQoSLevel($firstByte));

        // Duplicate message must be checked only on QoS > 0, else set it to false
        $this->isRedelivery = false;
        if ($firstByte & 8 && $this->message->getQoSLevel() !== 0) {
            // Is a duplicate is always bit 3 of first byte
            $this->isRedelivery = true;
        }

        return $this;
    }

    /**
     * Finds out the QoS level in a fixed header for the Publish object
     *
     * @param int $bitString
     * @return int
     * @throws \unreal4u\MQTT\Exceptions\InvalidQoSLevel
     */
    private function determineIncomingQoSLevel(int $bitString): int
    {
        // QoS lvl 6 does not exist, throw exception
        if (($bitString & 6) >= 6) {
            throw new InvalidQoSLevel('Invalid QoS level "' . $bitString . '" found (both bits set?)');
        }

        // Strange operation, why? Because 4 == QoS lvl2; 2 == QoS lvl1, 0 == QoS lvl0
        return $bitString & 4 / 2;
    }

    /**
     * Will perform sanity checks and fill in the Readable object with data
     * @param string $rawMQTTHeaders
     * @param ClientInterface $client
     * @return ReadableContentInterface
     * @throws \OutOfRangeException
     */
    public function fillObject(string $rawMQTTHeaders, ClientInterface $client): ReadableContentInterface
    {
        if (\strlen($rawMQTTHeaders) === 1) {
            $this->logger->debug('Fast check, read rest of data from socket');
            $restOfBytes = $client->readSocketData(1);
            $payload = $client->readSocketData(\ord($restOfBytes));
        } else {
            $this->logger->debug('Slow form, retransform data and read rest of data');
            $restOfBytes = $rawMQTTHeaders{1};
            $payload = substr($rawMQTTHeaders, 2);
            $exactRest = \ord($restOfBytes) - \strlen($payload);
            $payload .= $client->readSocketData($exactRest);
            $rawMQTTHeaders = $rawMQTTHeaders{0};
        }

        // At this point, $rawMQTTHeaders will be always 1 byte long
        $this->message = new Message();
        $this->analyzeFirstByte(\ord($rawMQTTHeaders));
        // $rawMQTTHeaders may be redefined
        $rawMQTTHeaders = $rawMQTTHeaders . $restOfBytes . $payload;

        // Topic size is always the 3rd byte
        $topicSize = \ord($rawMQTTHeaders{3});

        $messageStartPosition = 4;
        if ($this->message->getQoSLevel() > 0) {
            // [2 (fixed header) + 2 (topic size) + $topicSize] marks the beginning of the 2 packet identifier bytes
            $this->packetIdentifier = Utilities::convertBinaryStringToNumber(
                $rawMQTTHeaders{5 + $topicSize} . $rawMQTTHeaders{4 + $topicSize}
            );
            $messageStartPosition += 2;
        }

        $this->logger->debug('Determined headers', [
            'topicSize' => $topicSize,
            'QoSLevel' => $this->message->getQoSLevel(),
            'isDuplicate' => $this->isRedelivery,
            'isRetained' => $this->message->isRetained(),
            'packetIdentifier' => $this->packetIdentifier,
        ]);

        $this->message->setPayload(substr($rawMQTTHeaders, $messageStartPosition + $topicSize));
        $this->message->setTopicName(substr($rawMQTTHeaders, $messageStartPosition, $topicSize));

        return $this;
    }

    /**
     * @inheritdoc
     * @throws \unreal4u\MQTT\Exceptions\ServerClosedConnection
     * @throws \unreal4u\MQTT\Exceptions\NotConnected
     * @throws \unreal4u\MQTT\Exceptions\Connect\NoConnectionParametersDefined
     */
    public function performSpecialActions(ClientInterface $client, WritableContentInterface $originalRequest): bool
    {
        if ($this->message->getQoSLevel() === 0) {
            $this->logger->debug('No response needed', ['qosLevel', $this->message->getQoSLevel()]);
        } else {
            if ($this->message->getQoSLevel() === 1) {
                $this->logger->debug('Responding with PubAck', ['qosLevel' => $this->message->getQoSLevel()]);
                $client->sendData($this->composePubAckAnswer());
            } elseif ($this->message->getQoSLevel() === 2) {
                $this->logger->debug('Responding with PubRec', ['qosLevel' => $this->message->getQoSLevel()]);
                $client->sendData(new PubRec($this->logger));
            }
        }

        return true;
    }

    /**
     * Composes a PubAck answer with the same packetIdentifier as what we received
     * @return PubAck
     */
    private function composePubAckAnswer(): PubAck
    {
        $pubAck = new PubAck($this->logger);
        $pubAck->packetIdentifier = $this->packetIdentifier;
        return $pubAck;
    }
}


1		<?php
2
3		declare(strict_types=1);
4
5		namespace unreal4u\MQTT\Protocol;
6
7		use unreal4u\MQTT\Application\EmptyReadableResponse;
8		use unreal4u\MQTT\Application\Message;
9		use unreal4u\MQTT\Exceptions\InvalidQoSLevel;
10		use unreal4u\MQTT\Internals\ClientInterface;
11		use unreal4u\MQTT\Internals\ProtocolBase;
12		use unreal4u\MQTT\Internals\ReadableContent;
13		use unreal4u\MQTT\Internals\ReadableContentInterface;
14		use unreal4u\MQTT\Internals\WritableContent;
15		use unreal4u\MQTT\Internals\WritableContentInterface;
16		use unreal4u\MQTT\Utilities;
17
18		/**
19		* A PUBLISH Control Packet is sent from a Client to a Server or vice-versa to transport an Application Message.
20		*
21		* @see http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718037
22		*/
23		final class Publish extends ProtocolBase implements ReadableContentInterface, WritableContentInterface
24		{
25		use ReadableContent;
26		use WritableContent;
27
28		const CONTROL_PACKET_VALUE = 3;
29
30		/**
31		* Contains the message to be sent
32		* @var Message
33		*/
34		private $message;
35
36		/**
37		* Some interchanges with the broker will send or receive a packet identifier
38		* @var int
39		*/
40		public $packetIdentifier = 0;
41
42		/**
43		* Flag to check whether a message is a redelivery (DUP flag)
44		* @see http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718038
45		* @var bool
46		*/
47		public $isRedelivery = false;
48
49	4	public function createVariableHeader(): string
50		{
51	4	if ($this->message === null) {
52	1	throw new \InvalidArgumentException('You must at least provide a message object with a topic name');
53		}
54
55	3	$bitString = $this->createUTF8String($this->message->getTopicName());
56		// Reset the special flags should the object be reused with another message
57	3	$this->specialFlags = 0;
58
59	3	if ($this->isRedelivery) {
60		$this->logger->debug('Activating redelivery bit');
61		// DUP flag: if the message is a re-delivery, mark it as such
62		$this->specialFlags \|= 8;
63		}
64
65		// Check QoS level and perform the corresponding actions
66	3	if ($this->message->getQoSLevel() !== 0) {
67		// 2 for QoS lvl1 and 4 for QoS lvl2
68	2	$this->specialFlags \|= ($this->message->getQoSLevel() * 2);
69	2	$this->packetIdentifier++;
70	2	$bitString .= Utilities::convertNumberToBinaryString($this->packetIdentifier);
71	2	$this->logger->debug(sprintf('Activating QoS level %d bit', $this->message->getQoSLevel()), [
72	2	'specialFlags' => $this->specialFlags,
73		]);
74		}
75
76	3	if ($this->message->isRetained()) {
77		// RETAIN flag: should the server retain the message?
78	1	$this->specialFlags \|= 1;
79	1	$this->logger->debug('Activating retain flag', ['specialFlags' => $this->specialFlags]);
80		}
81
82	3	$this->logger->info('Variable header created', ['specialFlags' => $this->specialFlags]);
83
84	3	return $bitString;
85		}
86
87		public function createPayload(): string
88		{
89		if (!$this->message->validateMessage()) {
90		throw new \InvalidArgumentException('Invalid message');
91		}
92
93		return $this->message->getPayload();
94		}
95
96		/**
97		* QoS level 0 does not have to wait for a answer, so return false. Any other QoS level returns true
98		* @return bool
99		*/
100	4	public function shouldExpectAnswer(): bool
101		{
102	4	$shouldExpectAnswer = !($this->message->getQoSLevel() === 0);
103	4	$this->logger->debug('Checking whether we should expect an answer or not', [
104	4	'shouldExpectAnswer' => $shouldExpectAnswer,
105		]);
106	4	return $shouldExpectAnswer;
107		}
108
109	2	public function expectAnswer(string $data, ClientInterface $client): ReadableContentInterface
110		{
111	2	if ($this->shouldExpectAnswer() === false) {
112	1	return new EmptyReadableResponse($this->logger);
113		}
114
115	1	$pubAck = new PubAck($this->logger);
116	1	$pubAck->instantiateObject($data, $client);
117	1	return $pubAck;
118		}
119
120		/**
121		* Sets the to be sent message
122		*
123		* @param Message $message
124		* @return WritableContentInterface
125		*/
126	6	public function setMessage(Message $message): WritableContentInterface
127		{
128	6	$this->message = $message;
129	6	return $this;
130		}
131
132		/**
133		* Gets the set message
134		*
135		* @return Message
136		*/
137		public function getMessage(): Message
138		{
139		return $this->message;
140		}
141
142		/**
143		* Sets several bits and pieces from the first byte of the fixed header for the Publish packet
144		*
145		* @param int $firstByte
146		* @return Publish
147		* @throws \unreal4u\MQTT\Exceptions\InvalidQoSLevel
148		*/
149		private function analyzeFirstByte(int $firstByte): Publish
150		{
151		$this->logger->debug('Analyzing first byte', [sprintf('%08d', decbin($firstByte))]);
152		// Retained bit is bit 0 of first byte
153		$this->message->setRetainFlag(false);
154		if ($firstByte & 1) {
155		$this->message->setRetainFlag(true);
156		}
157		// QoS level are the last bits 2 & 1 of the first byte
158		$this->message->setQoSLevel($this->determineIncomingQoSLevel($firstByte));
159
160		// Duplicate message must be checked only on QoS > 0, else set it to false
161		$this->isRedelivery = false;
162		if ($firstByte & 8 && $this->message->getQoSLevel() !== 0) {
163		// Is a duplicate is always bit 3 of first byte
164		$this->isRedelivery = true;
165		}
166
167		return $this;
168		}
169
170		/**
171		* Finds out the QoS level in a fixed header for the Publish object
172		*
173		* @param int $bitString
174		* @return int
175		* @throws \unreal4u\MQTT\Exceptions\InvalidQoSLevel
176		*/
177		private function determineIncomingQoSLevel(int $bitString): int
178		{
179		// QoS lvl 6 does not exist, throw exception
180		if (($bitString & 6) >= 6) {
181		throw new InvalidQoSLevel('Invalid QoS level "' . $bitString . '" found (both bits set?)');
182		}
183
184		// Strange operation, why? Because 4 == QoS lvl2; 2 == QoS lvl1, 0 == QoS lvl0
185		return $bitString & 4 / 2;
186		}
187
188		/**
189		* Will perform sanity checks and fill in the Readable object with data
190		* @param string $rawMQTTHeaders
191		* @param ClientInterface $client
192		* @return ReadableContentInterface
193		* @throws \OutOfRangeException
194		*/
195		public function fillObject(string $rawMQTTHeaders, ClientInterface $client): ReadableContentInterface
196		{
197		if (\strlen($rawMQTTHeaders) === 1) {
198		$this->logger->debug('Fast check, read rest of data from socket');
199		$restOfBytes = $client->readSocketData(1);
200		$payload = $client->readSocketData(\ord($restOfBytes));
201		} else {
202		$this->logger->debug('Slow form, retransform data and read rest of data');
203		$restOfBytes = $rawMQTTHeaders{1};
204		$payload = substr($rawMQTTHeaders, 2);
205		$exactRest = \ord($restOfBytes) - \strlen($payload);
206		$payload .= $client->readSocketData($exactRest);
207		$rawMQTTHeaders = $rawMQTTHeaders{0};
208		}
209
210		// At this point, $rawMQTTHeaders will be always 1 byte long
211		$this->message = new Message();
212		$this->analyzeFirstByte(\ord($rawMQTTHeaders));
213		// $rawMQTTHeaders may be redefined
214		$rawMQTTHeaders = $rawMQTTHeaders . $restOfBytes . $payload;
215
216		// Topic size is always the 3rd byte
217		$topicSize = \ord($rawMQTTHeaders{3});
218
219		$messageStartPosition = 4;
220		if ($this->message->getQoSLevel() > 0) {
221		// [2 (fixed header) + 2 (topic size) + $topicSize] marks the beginning of the 2 packet identifier bytes
222		$this->packetIdentifier = Utilities::convertBinaryStringToNumber(
223		$rawMQTTHeaders{5 + $topicSize} . $rawMQTTHeaders{4 + $topicSize}
224		);
225		$messageStartPosition += 2;
226		}
227
228		$this->logger->debug('Determined headers', [
229		'topicSize' => $topicSize,
230		'QoSLevel' => $this->message->getQoSLevel(),
231		'isDuplicate' => $this->isRedelivery,
232		'isRetained' => $this->message->isRetained(),
233		'packetIdentifier' => $this->packetIdentifier,
234		]);
235
236		$this->message->setPayload(substr($rawMQTTHeaders, $messageStartPosition + $topicSize));
237		$this->message->setTopicName(substr($rawMQTTHeaders, $messageStartPosition, $topicSize));
238
239		return $this;
240		}
241
242		/**
243		* @inheritdoc
244		* @throws \unreal4u\MQTT\Exceptions\ServerClosedConnection
245		* @throws \unreal4u\MQTT\Exceptions\NotConnected
246		* @throws \unreal4u\MQTT\Exceptions\Connect\NoConnectionParametersDefined
247		*/
248		public function performSpecialActions(ClientInterface $client, WritableContentInterface $originalRequest): bool
249		{
250		if ($this->message->getQoSLevel() === 0) {
251		$this->logger->debug('No response needed', ['qosLevel', $this->message->getQoSLevel()]);
252		} else {
253		if ($this->message->getQoSLevel() === 1) {
254		$this->logger->debug('Responding with PubAck', ['qosLevel' => $this->message->getQoSLevel()]);
255		$client->sendData($this->composePubAckAnswer());
256		} elseif ($this->message->getQoSLevel() === 2) {
257		$this->logger->debug('Responding with PubRec', ['qosLevel' => $this->message->getQoSLevel()]);
258		$client->sendData(new PubRec($this->logger));
259		}
260		}
261
262		return true;
263		}
264
265		/**
266		* Composes a PubAck answer with the same packetIdentifier as what we received
267		* @return PubAck
268		*/
269		private function composePubAckAnswer(): PubAck
270		{
271		$pubAck = new PubAck($this->logger);
272		$pubAck->packetIdentifier = $this->packetIdentifier;
273		return $pubAck;
274		}
275		}
276

unreal4u / mqtt

Push — master ( 49fa37...dabd6a )

Publish::composePubAckAnswer() A

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