# jsonic
Fast, small JSON parsing library for rust with no dependencies
[](./LICENSE-MIT)
[](./LICENSE-APACHE)
[](https://crates.io/crates/jsonic)
[](https://github.com/g1mv/jsonic/actions)
### Quick overview
**jsonic** is a JSON parser. It aims at providing high-speed extraction of JSON data.
It does not convert JSON to structs at this stage.
### Performance
Here are some of the design choices for this library:
* small-footprint data structures to speedup memory/cache access
* object containers with hybrid data structures, using arrays to store low numbers of key/value pairs, and binary tree maps otherwise
* binary tree maps insertion/fetch speed enhanced by use of fast hashing on keys
* no data copying, source text data is never copied
* type conversions done on a per-request basis
**jsonic** does not make use of any particular instruction set/platform-specific optimization, so should have portable performance on all rust-compatible systems.
### Example use
```rust
fn main() {
let json = "{\"jsonic\": \"Fast, small JSON parsing library for rust with no dependencies\"}";
match jsonic::parse(json) {
Ok(parsed) => { println!("Describe jsonic? {:?}", parsed["jsonic"].as_str()); }
Err(error) => { eprintln!("{}", error); }
}
}
```
### Benchmark
To get an overview of **jsonic**'s parsing performance compared to other JSON parsing engines written in rust, use ```cargo bench```.
Here is a sample run on an Apple iMac M1, 8GB RAM, macOS Sonoma:
```shell
Running benches/json-rust.rs (target/release/deps/json_rust-0d2370885fb224f4)
Timer precision: 41 ns
json_rust fastest │ slowest │ median │ mean │ samples │ iters
╰─ parse │ │ │ │ │
├─ ./benches/data/canada.json 5.66 ms │ 6.038 ms │ 5.781 ms │ 5.764 ms │ 100 │ 100
├─ ./benches/data/citm_catalog.json 2.028 ms │ 2.309 ms │ 2.05 ms │ 2.055 ms │ 100 │ 100
╰─ ./benches/data/twitter.json 823.4 µs │ 1.027 ms │ 832 µs │ 835.4 µs │ 100 │ 100
Running benches/jsonic.rs (target/release/deps/jsonic-0031ab613974bf81)
Timer precision: 41 ns
jsonic fastest │ slowest │ median │ mean │ samples │ iters
╰─ parse │ │ │ │ │
├─ ./benches/data/canada.json 2.519 ms │ 3.089 ms │ 2.549 ms │ 2.565 ms │ 100 │ 100
├─ ./benches/data/citm_catalog.json 1.453 ms │ 1.633 ms │ 1.477 ms │ 1.479 ms │ 100 │ 100
╰─ ./benches/data/twitter.json 555.3 µs │ 658.9 µs │ 560.5 µs │ 563.2 µs │ 100 │ 100
Running benches/serde_json.rs (target/release/deps/serde_json-b37e83074b30325e)
Timer precision: 41 ns
serde_json fastest │ slowest │ median │ mean │ samples │ iters
╰─ parse │ │ │ │ │
├─ ./benches/data/canada.json 4.489 ms │ 4.977 ms │ 4.561 ms │ 4.58 ms │ 100 │ 100
├─ ./benches/data/citm_catalog.json 2.177 ms │ 2.961 ms │ 2.223 ms │ 2.231 ms │ 100 │ 100
╰─ ./benches/data/twitter.json 1.031 ms │ 1.203 ms │ 1.041 ms │ 1.046 ms │ 100 │ 100
Running benches/simd-json.rs (target/release/deps/simd_json-274159a472ebf0bc)
Timer precision: 41 ns
simd_json fastest │ slowest │ median │ mean │ samples │ iters
╰─ parse │ │ │ │ │
├─ ./benches/data/canada.json 5.494 ms │ 6.828 ms │ 5.709 ms │ 5.716 ms │ 100 │ 100
├─ ./benches/data/citm_catalog.json 2.695 ms │ 3.883 ms │ 2.766 ms │ 2.78 ms │ 100 │ 100
╰─ ./benches/data/twitter.json 1.114 ms │ 1.726 ms │ 1.127 ms │ 1.162 ms │ 100 │ 100
Running benches/sonic-rs.rs (target/release/deps/sonic_rs-0ab724f2d9eb477b)
Timer precision: 41 ns
sonic_rs fastest │ slowest │ median │ mean │ samples │ iters
╰─ parse │ │ │ │ │
├─ ./benches/data/canada.json 4.104 ms │ 4.794 ms │ 4.196 ms │ 4.217 ms │ 100 │ 100
├─ ./benches/data/citm_catalog.json 1.783 ms │ 2.662 ms │ 1.815 ms │ 1.845 ms │ 100 │ 100
╰─ ./benches/data/twitter.json 817.2 µs │ 1.025 ms │ 834 µs │ 834.5 µs │ 100 │ 100
```