1
|
|
|
<?php |
2
|
|
|
|
3
|
|
|
declare(strict_types=1); |
4
|
|
|
|
5
|
|
|
namespace unreal4u\MQTT\Protocol; |
6
|
|
|
|
7
|
|
|
use unreal4u\MQTT\Application\Topic; |
8
|
|
|
use unreal4u\MQTT\Exceptions\MustContainTopic; |
9
|
|
|
use unreal4u\MQTT\Internals\ProtocolBase; |
10
|
|
|
use unreal4u\MQTT\Internals\WritableContent; |
11
|
|
|
use unreal4u\MQTT\Internals\WritableContentInterface; |
12
|
|
|
use unreal4u\MQTT\Utilities; |
13
|
|
|
|
14
|
|
|
final class Unsubscribe extends ProtocolBase implements WritableContentInterface |
15
|
|
|
{ |
16
|
|
|
use WritableContent; |
17
|
|
|
|
18
|
|
|
const CONTROL_PACKET_VALUE = 10; |
19
|
|
|
|
20
|
|
|
private $packetIdentifier = 0; |
21
|
|
|
|
22
|
|
|
/** |
23
|
|
|
* An array of topics on which unsubscribe to |
24
|
|
|
* @var Topic[] |
25
|
|
|
*/ |
26
|
|
|
private $topics = []; |
27
|
|
|
|
28
|
|
|
/** |
29
|
|
|
* @return string |
30
|
|
|
* @throws \unreal4u\MQTT\Exceptions\MustContainTopic |
31
|
|
|
* @throws \OutOfRangeException |
32
|
|
|
* @throws \Exception |
33
|
|
|
*/ |
34
|
|
|
public function createVariableHeader(): string |
35
|
|
|
{ |
36
|
|
|
if (count($this->topics) === 0) { |
37
|
|
|
throw new MustContainTopic('An unsubscribe command must contain at least one topic'); |
38
|
|
|
} |
39
|
|
|
|
40
|
|
|
// Unsubscribe must always send a 2 flag |
41
|
|
|
$this->specialFlags = 2; |
42
|
|
|
|
43
|
|
|
// Assign a packet identifier automatically if none has been assigned yet |
44
|
|
|
if ($this->packetIdentifier === 0) { |
45
|
|
|
$this->setPacketIdentifier(random_int(0, 65535)); |
46
|
|
|
} |
47
|
|
|
|
48
|
|
|
return Utilities::convertNumberToBinaryString($this->packetIdentifier); |
49
|
|
|
} |
50
|
|
|
|
51
|
|
|
public function createPayload(): string |
52
|
|
|
{ |
53
|
|
|
$output = ''; |
54
|
|
|
foreach ($this->topics as $topic) { |
55
|
|
|
// chr on QoS level is safe because it will create an 8-bit flag where the first 6 are only 0's |
56
|
|
|
$output .= $this->createUTF8String($topic->getTopicName()); |
57
|
|
|
} |
58
|
|
|
return $output; |
59
|
|
|
} |
60
|
|
|
|
61
|
|
|
/** |
62
|
|
|
* When the Server receives a SUBSCRIBE Packet from a Client, the Server MUST respond with a SUBACK Packet |
63
|
|
|
* |
64
|
|
|
* This can however not be in the same order, as we may be able to receive PUBLISH packets before getting a SUBACK |
65
|
|
|
* back |
66
|
|
|
* |
67
|
|
|
* @see http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718134 (MQTT-3.8.4-1) |
68
|
|
|
* @return bool |
69
|
|
|
*/ |
70
|
|
|
public function shouldExpectAnswer(): bool |
71
|
|
|
{ |
72
|
|
|
return true; |
73
|
|
|
} |
74
|
|
|
|
75
|
|
|
/** |
76
|
|
|
* SUBSCRIBE Control Packets MUST contain a non-zero 16-bit Packet Identifier |
77
|
|
|
* |
78
|
|
|
* @param int $packetIdentifier |
79
|
|
|
* @return Unsubscribe |
80
|
|
|
* @throws \OutOfRangeException |
81
|
|
|
*/ |
82
|
|
|
public function setPacketIdentifier(int $packetIdentifier): self |
83
|
|
|
{ |
84
|
|
|
if ($packetIdentifier > 65535 || $packetIdentifier < 1) { |
85
|
|
|
throw new \OutOfRangeException('Packet identifier must fit within 2 bytes'); |
86
|
|
|
} |
87
|
|
|
|
88
|
|
|
$this->packetIdentifier = $packetIdentifier; |
89
|
|
|
$this->logger->debug('Setting packet identifier', ['current' => $this->packetIdentifier]); |
90
|
|
|
|
91
|
|
|
return $this; |
92
|
|
|
} |
93
|
|
|
|
94
|
|
|
public function getPacketIdentifier(): int |
95
|
|
|
{ |
96
|
|
|
return $this->packetIdentifier; |
97
|
|
|
} |
98
|
|
|
|
99
|
|
|
/** |
100
|
|
|
* A subscription is based on filters, this function allows us to pass on filters |
101
|
|
|
* |
102
|
|
|
* @param Topic[] $topics |
103
|
|
|
* @return Unsubscribe |
104
|
|
|
*/ |
105
|
|
|
public function addTopics(Topic ...$topics): self |
106
|
|
|
{ |
107
|
|
|
$this->topics = $topics; |
108
|
|
|
$this->logger->debug('Topics added', ['totalTopics', count($this->topics)]); |
109
|
|
|
|
110
|
|
|
return $this; |
111
|
|
|
} |
112
|
|
|
} |
113
|
|
|
|