mqute-codec 0.4.2

A full-featured implementation of MQTT protocol serialization in Rust, supporting versions 3.1, 3.1.1 and 5.0.
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
macro_rules! ack_properties {
    ($name:ident) => {
        #[doc = concat!("Represents an MQTT `", stringify!($name), "` packet")]
        #[doc = ""]
        #[doc = "Contains optional properties for MQTT v5 acknowledgment packet "]
        #[doc = "that provide additional metadata about the operation."]
        #[doc = ""]
        #[doc = "# Example"]
        #[doc = "```rust"]
        #[doc = concat!("use mqute_codec::protocol::v5::", stringify!($name), ";")]
        #[doc = concat!("let properties = ", stringify!($name), " {")]
        #[doc = "    reason_string: Some(String::from(\"value\")),"]
        #[doc = "    user_properties: vec![(String::from(\"key\"), String::from(\"value\"))],"]
        #[doc = "};"]
        #[doc = "```"]
        #[derive(Debug, Default, Clone, PartialEq, Eq)]
        pub struct $name {
            /// Human-readable description of the acknowledgement
            pub reason_string: Option<String>,
            /// User-defined key-value properties for extended functionality
            pub user_properties: Vec<(String, String)>,
        }
    };
}

macro_rules! ack_properties_frame_impl {
    ($name:ident) => {
        impl $crate::protocol::v5::property::PropertyFrame for $name {
            fn encoded_len(&self) -> usize {
                let mut len = 0usize;

                len += $crate::protocol::v5::property::property_len!(&self.reason_string);
                len += $crate::protocol::v5::property::property_len!(&self.user_properties);

                len
            }

            fn encode(&self, buf: &mut bytes::BytesMut) {
                $crate::protocol::v5::property::property_encode!(
                    &self.reason_string,
                    $crate::protocol::v5::property::Property::ReasonString,
                    buf
                );
                $crate::protocol::v5::property::property_encode!(
                    &self.user_properties,
                    $crate::protocol::v5::property::Property::UserProp,
                    buf
                );
            }

            fn decode(buf: &mut bytes::Bytes) -> Result<Option<Self>, $crate::Error>
            where
                Self: Sized,
            {
                use bytes::Buf;

                if buf.is_empty() {
                    return Ok(None);
                }

                let mut reason_string: Option<String> = None;
                let mut user_properties: Vec<(String, String)> = Vec::new();

                while buf.has_remaining() {
                    let property: $crate::protocol::v5::property::Property =
                        $crate::codec::util::decode_byte(buf)?.try_into()?;
                    match property {
                        $crate::protocol::v5::property::Property::ReasonString => {
                            $crate::protocol::v5::property::property_decode!(
                                &mut reason_string,
                                buf
                            );
                        }
                        $crate::protocol::v5::property::Property::UserProp => {
                            $crate::protocol::v5::property::property_decode!(
                                &mut user_properties,
                                buf
                            );
                        }
                        _ => return Err($crate::Error::PropertyMismatch),
                    }
                }

                Ok(Some($name {
                    reason_string,
                    user_properties,
                }))
            }
        }
    };
}

macro_rules! ack {
    ($name:ident, $properties:ident, $check:ident) => {
        #[derive(Debug, Clone, PartialEq, Eq)]
        pub(crate) struct Header {
            packet_id: u16,
            code: $crate::protocol::v5::reason::ReasonCode,
            properties: Option<$properties>,
        }

        impl Header {
            pub(crate) fn new(
                packet_id: u16,
                code: $crate::protocol::v5::reason::ReasonCode,
                properties: Option<$properties>,
            ) -> Self {
                if packet_id == 0 {
                    panic!("Packet id is zero");
                }

                if !$check(code) {
                    panic!("Invalid reason code {code}");
                }

                Header {
                    packet_id,
                    code,
                    properties,
                }
            }

            pub(crate) fn encoded_len(&self) -> usize {
                use $crate::protocol::v5::property::PropertyFrame;

                // The reason code and property length can be omitted
                // if the reason code is 'Success' and there are no properties
                if self.properties.is_none()
                    && self.code == $crate::protocol::v5::reason::ReasonCode::Success
                {
                    return 2;
                }

                let properties_len = self
                    .properties
                    .as_ref()
                    .map(|properties| properties.encoded_len())
                    .unwrap_or(0);

                2 + 1 + $crate::protocol::util::len_bytes(properties_len) + properties_len
            }

            pub(crate) fn encode(&self, buf: &mut bytes::BytesMut) -> Result<(), $crate::Error> {
                use bytes::BufMut;
                use $crate::protocol::v5::property::PropertyFrame;

                buf.put_u16(self.packet_id);

                // The reason code and property length can be omitted
                // if the reason code is 'Success' and there are no properties
                if self.properties.is_none()
                    && self.code == $crate::protocol::v5::reason::ReasonCode::Success
                {
                    return Ok(());
                }

                buf.put_u8(self.code.into());

                let properties_len = self
                    .properties
                    .as_ref()
                    .map(|properties| properties.encoded_len())
                    .unwrap_or(0) as u32;

                // Encode properties len
                $crate::codec::util::encode_variable_integer(buf, properties_len)?;

                // Encode properties
                if let Some(properties) = self.properties.as_ref() {
                    properties.encode(buf);
                }

                Ok(())
            }

            pub(crate) fn decode(payload: &mut bytes::Bytes) -> Result<Self, $crate::Error> {
                use bytes::Buf;
                use $crate::protocol::v5::property::PropertyFrame;

                let packet_id = $crate::codec::util::decode_word(payload)?;

                if payload.is_empty() {
                    return Ok(Header {
                        packet_id,
                        code: $crate::protocol::v5::reason::ReasonCode::Success,
                        properties: None,
                    });
                }

                let code = $crate::codec::util::decode_byte(payload)?.try_into()?;

                if !$check(code) {
                    return Err($crate::Error::InvalidReasonCode(code.into()));
                }

                let properties_len =
                    $crate::codec::util::decode_variable_integer(&payload)? as usize;
                if payload.len()
                    < properties_len + $crate::protocol::util::len_bytes(properties_len)
                {
                    return Err($crate::Error::MalformedPacket);
                }

                // Skip properties len
                payload.advance($crate::protocol::util::len_bytes(properties_len));

                let mut frame = payload.split_to(properties_len);
                let properties = $properties::decode(&mut frame)?;

                Ok(Header {
                    packet_id,
                    code,
                    properties,
                })
            }
        }

        #[doc = concat!("Represents an MQTT `", stringify!($name), "` packet")]
        #[doc = ""]
        #[doc = "# Example"]
        #[doc = ""]
        #[doc = "```rust"]
        #[doc = concat!("use mqute_codec::protocol::v5::{ReasonCode, ", stringify!($name), "};")]
        #[doc = ""]
        #[doc = concat!("let packet = ", stringify!($name), "::new(1234, ReasonCode::Success, None);")]
        #[doc = "assert_eq!(packet.packet_id(), 1234u16);"]
        #[doc = "assert_eq!(packet.code(), ReasonCode::Success);"]
        #[doc = "```"]
        #[derive(Debug, Clone, PartialEq, Eq)]
        pub struct $name {
            header: Header,
        }

        impl $name {
            #[doc = concat!("Creates a new `", stringify!($name), "` packet")]
            pub fn new(packet_id: u16, code: ReasonCode, properties: Option<$properties>) -> Self {
                $name {
                    header: Header::new(packet_id, code, properties),
                }
            }

            #[doc = concat!("Returns the packet ID of the `", stringify!($name), "` packet")]
            pub fn packet_id(&self) -> u16 {
                self.header.packet_id
            }

            #[doc = concat!("Returns the reason code of the `", stringify!($name), "` packet")]
            pub fn code(&self) -> $crate::protocol::v5::reason::ReasonCode {
                self.header.code
            }

            #[doc = concat!("Returns the `", stringify!($name), "` properties if present")]
            pub fn properties(&self) -> Option<$properties> {
                self.header.properties.clone()
            }
        }
    };
}

macro_rules! ack_encode_impl {
    ($name:ident, $packet_type:expr, $flags:expr) => {
        impl $crate::codec::Encode for $name {
            fn encode(&self, buf: &mut bytes::BytesMut) -> Result<(), $crate::Error> {
                let header = $crate::protocol::FixedHeader::with_flags(
                    $packet_type,
                    $flags,
                    self.payload_len(),
                );
                header.encode(buf)?;

                self.header.encode(buf)
            }

            fn payload_len(&self) -> usize {
                self.header.encoded_len()
            }
        }
    };
}

macro_rules! ack_decode_impl {
    ($name:ident, $packet_type:expr, $flags:expr, $check:ident) => {
        impl $crate::codec::Decode for $name {
            fn decode(mut packet: $crate::codec::RawPacket) -> Result<Self, $crate::Error> {
                if packet.header.packet_type() != $packet_type || packet.header.flags() != $flags {
                    return Err($crate::Error::MalformedPacket);
                }

                let header = Header::decode(&mut packet.payload)?;
                Ok($name { header })
            }
        }
    };
}

macro_rules! ping_packet_decode_impl {
    ($packet:ident, $packet_type:expr) => {
        impl $crate::codec::Decode for $packet {
            fn decode(packet: $crate::codec::RawPacket) -> Result<Self, $crate::Error> {
                if packet.header.packet_type() == $packet_type && packet.header.flags().is_default()
                {
                    Ok($packet {})
                } else {
                    Err($crate::Error::MalformedPacket)
                }
            }
        }
    };
}

macro_rules! ping_packet_encode_impl {
    ($packet:ident, $packet_type:expr) => {
        impl $crate::codec::Encode for $packet {
            fn encode(&self, buf: &mut bytes::BytesMut) -> Result<(), $crate::Error> {
                let header = $crate::protocol::FixedHeader::new($packet_type, 0);
                header.encode(buf)
            }

            fn payload_len(&self) -> usize {
                // No payload
                0
            }
        }
    };
}

macro_rules! id_header {
    ($name:ident, $properties:ident) => {
        #[derive(Debug, Clone, PartialEq, Eq)]
        struct $name {
            packet_id: u16,
            properties: Option<$properties>,
        }

        impl $name {
            pub(crate) fn new(packet_id: u16, properties: Option<$properties>) -> Self {
                $name {
                    packet_id,
                    properties,
                }
            }

            pub(crate) fn encoded_len(&self) -> usize {
                use $crate::protocol::v5::property::PropertyFrame;

                let properties_len = self
                    .properties
                    .as_ref()
                    .map(|properties| properties.encoded_len())
                    .unwrap_or(0);

                2 + $crate::protocol::util::len_bytes(properties_len) + properties_len
            }

            pub(crate) fn encode(&self, buf: &mut bytes::BytesMut) -> Result<(), $crate::Error> {
                use bytes::BufMut;
                use $crate::protocol::v5::property::PropertyFrame;

                buf.put_u16(self.packet_id);

                let properties_len = self
                    .properties
                    .as_ref()
                    .map(|properties| properties.encoded_len())
                    .unwrap_or(0) as u32;

                // Encode properties len
                $crate::codec::util::encode_variable_integer(buf, properties_len)?;

                // Encode properties
                if let Some(properties) = self.properties.as_ref() {
                    properties.encode(buf);
                }

                Ok(())
            }

            pub(crate) fn decode(payload: &mut Bytes) -> Result<Self, $crate::Error> {
                use $crate::protocol::v5::property::PropertyFrame;

                let packet_id = $crate::codec::util::decode_word(payload)?;

                let properties_len =
                    $crate::codec::util::decode_variable_integer(payload)? as usize;
                if payload.len()
                    < properties_len + $crate::protocol::util::len_bytes(properties_len)
                {
                    return Err($crate::Error::MalformedPacket);
                }

                // Skip variable byte
                payload.advance($crate::protocol::util::len_bytes(properties_len));

                let mut properties_buf = payload.split_to(properties_len);

                // Deserialize properties
                let properties = $properties::decode(&mut properties_buf)?;
                Ok($name {
                    packet_id,
                    properties,
                })
            }
        }
    };
}

pub(crate) use ack;
pub(crate) use ack_decode_impl;
pub(crate) use ack_encode_impl;
pub(crate) use ack_properties;
pub(crate) use ack_properties_frame_impl;
pub(crate) use id_header;
pub(crate) use ping_packet_decode_impl;
pub(crate) use ping_packet_encode_impl;