40 releases (18 breaking)
0.19.0 | Dec 17, 2022 |
---|---|
0.18.0 | Jun 19, 2022 |
0.17.1 | Jun 1, 2022 |
0.15.0 | Mar 13, 2022 |
0.1.1 | Mar 29, 2020 |
#46 in Encoding
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Used in 176 crates
(52 directly)
175KB
4K
SLoC
minicbor
A small CBOR codec suitable for no_std
environments.
Documentation
Documentation is available at
License
This software is licensed under the Blue Oak Model License Version 1.0.0. If you are interested in contributing to this project, please read the file CONTRIBUTING.md first.
lib.rs
:
A small CBOR codec suitable for no_std
environments.
The crate is organised around the following entities:
-
[
Encoder
] and [Decoder
] for type-directed encoding and decoding of values. -
[
Encode
] and [Decode
] traits which can be implemented for any type that should be encoded to or decoded from CBOR. They are similar to serde'sSerialize
andDeserialize
traits but do not abstract over the encoder/decoder.
Encoding and decoding proceeds in a type-directed way, i.e. by calling
methods for expected data item types, e.g. [Decoder::u32
] or
[Encoder::str
]. In addition there is support for data type inspection.
The Decoder
can be queried for the current data type which returns a
[data::Type
] that can represent every possible CBOR type and decoding
can thus proceed based on this information. It is also possible to just
tokenize the input bytes using a Tokenizer
, i.e.
an Iterator
over CBOR Token
s. Finally, the length
in bytes of a value's CBOR representation can be calculated if the
value's type implements the [CborLen
] trait.
Optionally, Encode
and Decode
can be derived for structs and enums
using the respective derive macros (requires feature "derive"
).
See [minicbor_derive
] for details.
For I/O support see minicbor-io
.
Feature flags
The following feature flags are supported:
-
"alloc"
: Enables most collection types in ano_std
environment. -
"std"
: Implies"alloc"
and enables more functionality that depends on thestd
crate. -
"derive"
: Allows deriving [Encode
] and [Decode
] traits.
Example: generic encoding and decoding
use minicbor::{Encode, Decode};
let input = ["hello", "world"];
let mut buffer = [0u8; 128];
minicbor::encode(&input, buffer.as_mut())?;
let output: [&str; 2] = minicbor::decode(buffer.as_ref())?;
assert_eq!(input, output);
# Ok::<_, Box<dyn std::error::Error>>(())
Example: ad-hoc encoding
use minicbor::Encoder;
let mut buffer = [0u8; 128];
let mut encoder = Encoder::new(&mut buffer[..]);
encoder.begin_map()? // using an indefinite map here
.str("hello")?.str("world")?
.str("submap")?.map(2)?
.u8(1)?.bool(true)?
.u8(2)?.bool(false)?
.u16(34234)?.array(3)?.u8(1)?.u8(2)?.u8(3)?
.bool(true)?.null()?
.end()?;
# Ok::<_, Box<dyn std::error::Error>>(())
Example: ad-hoc decoding
use minicbor::Decoder;
use minicbor::data::Tag;
let input = [
0xc0, 0x74, 0x32, 0x30, 0x31, 0x33, 0x2d, 0x30,
0x33, 0x2d, 0x32, 0x31, 0x54, 0x32, 0x30, 0x3a,
0x30, 0x34, 0x3a, 0x30, 0x30, 0x5a
];
let mut decoder = Decoder::new(&input);
assert_eq!(Tag::DateTime, decoder.tag()?);
assert_eq!("2013-03-21T20:04:00Z", decoder.str()?);
# Ok::<_, Box<dyn std::error::Error>>(())
Example: tokenization
use minicbor::display;
use minicbor::decode::{Token, Tokenizer};
let input = [0x83, 0x01, 0x9f, 0x02, 0x03, 0xff, 0x82, 0x04, 0x05];
assert_eq!("[1, [_ 2, 3], [4, 5]]", format!("{}", display(&input)));
let tokens = Tokenizer::new(&input).collect::<Result<Vec<Token>, _>>()?;
assert_eq! { &tokens[..],
&[Token::Array(3),
Token::U8(1),
Token::BeginArray,
Token::U8(2),
Token::U8(3),
Token::Break,
Token::Array(2),
Token::U8(4),
Token::U8(5)]
};
# Ok::<_, Box<dyn std::error::Error>>(())
Dependencies
~145KB