3 releases (breaking)
0.3.0 | Oct 31, 2024 |
---|---|
0.2.0 | May 14, 2024 |
0.1.0 | May 11, 2024 |
#69 in No standard library
132 downloads per month
Used in 2 crates
27KB
454 lines
ser-write
Writer-style serializers and deserializers for convenience designed with embedded (no_std
) targets in mind.
- Writer-style serializers use the common writer trait found in this crate.
- Designed for
no_std
. - Fully supports
std
oralloc
when enabled for code portability and testablilty. - For each serializer a deserializer is provided for convenience.
- Embedded projects can implement
SerWrite
trait for custom containers, frame builders and more.
This crate provides:
- the trait -
SerWrite
which should be used by serializers to write the serialized output, SerError
- a convenient error type,SliceWriter
- a convenient slice writer object implementingSerWrite
,SerWrite
implementations for foreign types.
Depending on the enabled crate features, SerWrite
is implemented for:
SliceWriter
- example slice writer implementation,arrayvec::ArrayVec<u8,CAP>
-arrayvec
feature,heapless::Vec<u8,CAP>
-heapless
feature,smallvec::SmallVec<[u8; CAP]>
-smallvec
feature,tinyvec::ArrayVec<[u8; CAP]>
-tinyvec
feature,tinyvec::SliceVec<'_, u8>
-tinyvec
feature,tinyvec::TinyVec<[u8; CAP]>
-tinyvec
withalloc
orstd
feature,Vec<u8>
-alloc
orstd
feature,VecDeque<u8>
-alloc
orstd
feature,io::Cursor<T: io::Write>
-std
feature,
smallvec
also enables alloc
.
Usage
Start by adding a dependency to the serializer:
For example:
[dependencies]
ser-write-json = { version = "0.3", default-features = false }
If you want to also pull implementations of SerWrite
for the foreign types add:
ser-write = { version = "0.3", default-features = false, features = ["arrayvec", "heapless"] }
In the above example implementations for: arrayvec::ArrayVec<u8;_>
and heapless::Vec<u8>
are selected.
Serializers
Currently available serializers and deserializers are:
- JSON (compact) - ser-write-json
- MessagePack - ser-write-msgpack
Example
An example SliceWriter
implementation:
use ser_write::{SerWrite, SerResult, SerError};
#[derive(Debug, PartialEq)]
pub struct SliceWriter<'a> {
pub buf: &'a mut [u8],
pub len: usize
}
impl SerWrite for SliceWriter<'_> {
fn write(&mut self, buf: &[u8]) -> SerResult<()> {
let end = self.len + buf.len();
match self.buf.get_mut(self.len..end) {
Some(chunk) => {
chunk.copy_from_slice(buf);
self.len = end;
Ok(())
}
None => Err(SerError::BufferFull)
}
}
}
Alternatives
For alloc
only:
Alternatively there's a Rust Embedded Community crate for serializeing JSONs without std
:
- serde-json-core
- serde-json-core-fmt (a writer-style attempt abusing
fmt::Display
trait)
serde-json-core
is a true no_std
, no alloc
alternative but rather inconvenient. One has to serialize data into intermediate slices instead just pushing data to outgoing buffers or frame builder implementations.
Why though?
- This crate would not be needed once something like
io::Write
lands in the Rust core.
Rust Version Requirements
ser-write
requires Rustc version 1.81 or greater.
Dependencies
~215KB