Crate musli_wire
source ·Expand description
Fully upgrade stable format for Müsli suitable for network communication.
Wire encoding is fully upgrade stable:
- ✔ Can tolerate missing fields if they are annotated with
#[musli(default)]
. - ✔ Can skip over unknown fields.
This means that it’s suitable as a wire format, since the data model can evolve independently among clients. Once some clients are upgraded they will start sending unknown fields which non-upgraded clients will be forced to skip over for the duration of the upgrade.
use musli::{Encode, Decode};
#[derive(Debug, PartialEq, Encode, Decode)]
struct Version1 {
name: String,
}
#[derive(Debug, PartialEq, Encode, Decode)]
struct Version2 {
name: String,
#[musli(default)]
age: Option<u32>,
}
let version2 = musli_wire::to_buffer(&Version2 {
name: String::from("Aristotle"),
age: Some(62),
})?;
let version1: Version1 = musli_wire::decode(version2.as_slice())?;
assert_eq!(version1, Version1 {
name: String::from("Aristotle"),
});
Configuring
To configure the behavior of the wire format you can use the Encoding type:
use musli_wire::Encoding;
use musli_wire::int::{Fixed, Variable};
use musli::{Encode, Decode};
use musli::mode::DefaultMode;
const CONFIG: Encoding<DefaultMode, Fixed, Variable, 128> = Encoding::new()
.with_fixed_integers()
.with_max_pack::<128>();
#[derive(Debug, PartialEq, Encode, Decode)]
struct Struct<'a> {
name: &'a str,
age: u32,
}
let mut out = Vec::new();
let expected = Struct {
name: "Aristotle",
age: 61,
};
CONFIG.encode(&mut out, &expected)?;
let actual = CONFIG.decode(&out[..])?;
assert_eq!(expected, actual);
Implementation details
Each field is prefix typed with a single byte tag that allows a receiver to figure out exactly how much should be skipped over.
Packed items are prefix-length encoded, and have a limited size. Its exact length is defined by MAX_INLINE_LEN and can be modified with Encoding::with_max_pack.
Re-exports
pub use self::encoding::decode;
pub use self::encoding::encode;
pub use self::encoding::from_slice;
pub use self::encoding::to_buffer;
pub use self::encoding::to_fixed_bytes;
pub use self::encoding::Encoding;
pub use self::encoding::to_vec;
pub use self::encoding::to_writer;
Modules
- A writer which buffers the writes before it outputs it into the backing storage.
- A container which can store up to a fixed number of uninitialized bytes on the stack and read into and from it.
- Traits and utilities for dealing with integers.
- Trait for governing how a particular source of bytes is read.
- Type flags available for
musli-wire
. - Helpers for integrating musli with I/O types like std::io and std::io::Write.
- Trait for governing how a particular sink of bytes is written to.