Low-level representation of a message
that has been parsed from a byte array
To convert an iterator of bytes into a Message, there is a provided trait [`crate::TryFromBytes`].
```
use toad_msg::TryFromBytes;
use toad_msg::*;
# // version token len code (2.05 Content)
# // | | /
# // | type | / message ID
# // | | | | |
# // vv vv vvvv vvvvvvvv vvvvvvvvvvvvvvvv
# let header: [u8; 4] = 0b_01_00_0001_01000101_0000000000000001u32.to_be_bytes();
# let token: [u8; 1] = [254u8];
# let content_format: &[u8] = b"application/json";
# let options: [&[u8]; 2] = [&[0b_1100_1101u8, 0b00000011u8], content_format];
# let payload: [&[u8]; 2] = [&[0b_11111111u8], b"hello, world!"];
let packet: Vec<u8> = /* bytes! */
# [header.as_ref(), token.as_ref(), options.concat().as_ref(), payload.concat().as_ref()].concat();
// `VecMessage` uses `Vec` as the backing structure for byte buffers
let msg = VecMessage::try_from_bytes(packet.clone()).unwrap();
# let opt = Opt {
# delta: OptDelta(12),
# value: OptValue(content_format.iter().map(|u| *u).collect()),
# };
let mut opts_expected = /* create expected options */
# Vec::new();
# opts_expected.push(opt);
let expected = VecMessage {
id: Id(1),
ty: Type(0),
ver: Version(1),
token: Token(tinyvec::array_vec!([u8; 8] => 254)),
opts: opts_expected,
code: Code {class: 2, detail: 5},
payload: Payload(b"hello, world!".to_vec()),
__optc: Default::default(),
};
assert_eq!(msg, expected);
```
See [RFC7252 - Message Details](https://datatracker.ietf.org/doc/html/rfc7252#section-3) for context
