toad_msg/msg/
ty.rs

1use super::MessageParseError;
2
3/// Indicates if this message is of
4/// type Confirmable (0), Non-confirmable (1), Acknowledgement (2), or Reset (3).
5///
6/// See [RFC7252 - Message Details](https://datatracker.ietf.org/doc/html/rfc7252#section-3) for context
7#[derive(Copy, Clone, Hash, Eq, Ord, PartialEq, PartialOrd, Debug)]
8pub enum Type {
9  /// Some messages do not require an acknowledgement.  This is
10  /// particularly true for messages that are repeated regularly for
11  /// application requirements, such as repeated readings from a sensor.
12  Non,
13  /// Some messages require an acknowledgement.  These messages are
14  /// called "Confirmable".  When no packets are lost, each Confirmable
15  /// message elicits exactly one return message of type Acknowledgement
16  /// or type Reset.
17  Con,
18  /// An Acknowledgement message acknowledges that a specific
19  /// Confirmable message arrived.  By itself, an Acknowledgement
20  /// message does not indicate success or failure of any request
21  /// encapsulated in the Confirmable message, but the Acknowledgement
22  /// message may also carry a Piggybacked Response.
23  Ack,
24  /// A Reset message indicates that a specific message (Confirmable or
25  /// Non-confirmable) was received, but some context is missing to
26  /// properly process it.  This condition is usually caused when the
27  /// receiving node has rebooted and has forgotten some state that
28  /// would be required to interpret the message.  Provoking a Reset
29  /// message (e.g., by sending an Empty Confirmable message) is also
30  /// useful as an inexpensive check of the liveness of an endpoint
31  /// ("CoAP ping").
32  Reset,
33}
34
35impl TryFrom<u8> for Type {
36  type Error = MessageParseError;
37
38  fn try_from(b: u8) -> Result<Self, Self::Error> {
39    match b {
40      | 0 => Ok(Type::Con),
41      | 1 => Ok(Type::Non),
42      | 2 => Ok(Type::Ack),
43      | 3 => Ok(Type::Reset),
44      | _ => Err(MessageParseError::InvalidType(b)),
45    }
46  }
47}
toad_msg/msg/ty.rs

toad_msg/msg/
ty.rs
