rumqttc/mqttbytes/v4/
unsubscribe.rs

1use super::*;
2use bytes::{Buf, Bytes};
3
4/// Unsubscribe packet
5#[derive(Debug, Clone, PartialEq, Eq)]
6pub struct Unsubscribe {
7    pub pkid: u16,
8    pub topics: Vec<String>,
9}
10
11impl Unsubscribe {
12    pub fn new<S: Into<String>>(topic: S) -> Unsubscribe {
13        Unsubscribe {
14            pkid: 0,
15            topics: vec![topic.into()],
16        }
17    }
18
19    fn len(&self) -> usize {
20        // len of pkid + vec![subscribe topics len]
21        2 + self.topics.iter().fold(0, |s, t| s + t.len() + 2)
22    }
23
24    pub fn size(&self) -> usize {
25        let len = self.len();
26        let remaining_len_size = len_len(len);
27
28        1 + remaining_len_size + len
29    }
30
31    pub fn read(fixed_header: FixedHeader, mut bytes: Bytes) -> Result<Self, Error> {
32        let variable_header_index = fixed_header.fixed_header_len;
33        bytes.advance(variable_header_index);
34
35        let pkid = read_u16(&mut bytes)?;
36        let mut payload_bytes = fixed_header.remaining_len - 2;
37        let mut topics = Vec::with_capacity(1);
38
39        while payload_bytes > 0 {
40            let topic_filter = read_mqtt_string(&mut bytes)?;
41            payload_bytes -= topic_filter.len() + 2;
42            topics.push(topic_filter);
43        }
44
45        let unsubscribe = Unsubscribe { pkid, topics };
46        Ok(unsubscribe)
47    }
48
49    pub fn write(&self, payload: &mut BytesMut) -> Result<usize, Error> {
50        let remaining_len = self.len();
51
52        payload.put_u8(0xA2);
53        let remaining_len_bytes = write_remaining_length(payload, remaining_len)?;
54        payload.put_u16(self.pkid);
55
56        for topic in self.topics.iter() {
57            write_mqtt_string(payload, topic.as_str());
58        }
59        Ok(1 + remaining_len_bytes + remaining_len)
60    }
61}
rumqttc/mqttbytes/v4/unsubscribe.rs

rumqttc/mqttbytes/v4/
unsubscribe.rs
