quick-protobuf

A pure Rust library to serialize/deserialize protobuf files.

Documentation

Description

This library intends to provide a simple yet fast (minimal allocations) protobuf parser implementation.

It provides both: - pb-rs, a code generation tool: - each .proto file will generate a minimal rust module (one function to read, one to write, and one to compute the size of the messages) - each message will generate a rust struct where: - bytes fields are converted to Cow::Borrowed([u8]) - string fields are converted to Cow::Borrowed(str) - repeated fields are converted to Vec - all other fields are converted into the matching rust primitive type - no need to use google protoc tool to generate the modules - quick-protobuf, a protobuf file parser: - this is the crate that you will typically refer to in your library. The generated modules will assume it has been imported. - it acts like an event parser, the logic to convert it into struct is handle by pb-rs

Example: protobuf_example project

• 1. Use pb-rs binary, located into codegen directory to automatically generate a foobar.rs module from a foobar.proto proto file

sh git clone https://github.com/tafia/quick-protobuf cd quick-protobuf/codegen cargo run ../../protobuf_example/foo_bar.proto cd ../../protobuf_example

• 1. Add a dependency to quick-protobuf

```toml

Cargo.toml

[dependencies] quick-protobuf = "0.1.0" ```

• 1. Have fun

```rust // main.rs or lib.rs extern crate quick_protobuf;

mod foo_bar; // (see 1.)

use quick_protobuf::Reader;

// We will suppose here that Foo and Bar are two messages defined in the .proto file // and converted into rust structs // // FooBar is the root message defined like this: // message FooBar { // repeated Foo foos = 1; // repeated Bar bars = 2; // } use foo_bar::{FooBar};

fn main() { // create a reader, which will parse the protobuf binary file and pop events // this reader will read the entire file into an internal buffer let mut reader = Reader::from_file("/path/to/binary/protobuf.bin") .expect("Cannot read input file");

// use the generated module fns with the reader to convert your data into rust structs
let foobar = reader.read(FooBar::from_reader).expect("Cannot read FooBar message");

println!("Found {} foos and {} bars!", foobar.foos.len(), foobar.bars.len());

} ```

Why not rust-protobuf

This library is an alternative to the widely used rust-protobuf. If you want to build anything serious, I strongly advise against using quick-protobuf which is very immature for the moment.

Pros / Cons

• Pros

  • No need to install anything on your machine but rust
  • No trait objects: faster/simpler parser
  • Very simple generated modules (~10x smaller)
  • Less allocations (bytes and string are converted respectively to Cow::Borrowed([u8]) and Cow::Borrowed(str))

• Cons

  • Very immature library at the moment, many missing functionalities
  • Not a drop-in replacement of [rust-protobuf]
  • you have to handle Options unwrapping yourself
  • you may need to handle Cow as well is you want to modify it
  • Very little tests in comparison

Codegen

Have a look at the different generated modules for the same .proto file: - rust-protobuf: 2322 loc - quick-protobuf: 300 loc

Benchmarks

The only implemented benchmarks are the adaptation from rust-protobuf perftest.

Contribution

Any help is welcomed! (Pull requests of course, bug report, missing functionality etc...)

Licence

MIT