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https://github.com/lovasoa/json_in_type
Fast json encoder in rust, that encodes the structure of JSON values in their types
https://github.com/lovasoa/json_in_type
json performance rust
Last synced: 16 days ago
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Fast json encoder in rust, that encodes the structure of JSON values in their types
- Host: GitHub
- URL: https://github.com/lovasoa/json_in_type
- Owner: lovasoa
- License: bsd-2-clause
- Created: 2018-10-07T16:31:40.000Z (about 6 years ago)
- Default Branch: master
- Last Pushed: 2022-08-30T02:11:25.000Z (about 2 years ago)
- Last Synced: 2024-09-17T17:28:33.211Z (about 2 months ago)
- Topics: json, performance, rust
- Language: Rust
- Homepage: https://crates.io/crates/json_in_type
- Size: 14.1 MB
- Stars: 83
- Watchers: 6
- Forks: 4
- Open Issues: 6
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# json_in_type
Fast json encoder in rust, that does more at compile time, and less at run time.
One notable feature is the ability to encode the structure of JSON objects in their type.
This allows for a very compact representation of objects in memory, and up to an order of magnitude better performance
than the traditional approach (used by serde's `json!` marco, for instance) where JSON objects are stored in maps.
The goal of this library is to be as close as possible to the performance
and memory footprint you would get by writing the json by hand in your source code
and using string formatting to insert your dynamic values.
```rust
fn write_obj_bad(value: f32) -> String {
format!("{{\"value\":{}}}", value)
}
// Safer, but equivalent and not less efficient :
fn write_obj_good(value: f32) -> String {
( json_object! { value } ).to_json_string()
}
```
## Example use
```rust
use json_in_type::*;
fn main() {
let void = ();
let list = json_list![42u8, true];
let dynamic_key = "hello";
let json_val = json_object!{
void, list,
[dynamic_key]: "world"
};
/* The type of json_val is:
InlinedJSONObjectEntry<
(),
InlinedJSONObjectEntry<
JSONListElem>>,
JSONObjectEntry<
&str, &str,
JSONObjectEnd>>>
*/
assert_eq!(
r#"{"void":null,"list":[42,true],"hello":"world"}"#,
json_val.to_json_string()
);
}
```
## Memory use
The generated types have a very small memory footprint at runtime.
You don't pay for the json structure, only for what you put in it !
In the next example, we store the following json structure on only two bytes:
```json
{
"result_count" : 1,
"errors" : null,
"results" : [
{"answer":42, "ok":true}
]
}
```
```rust
fn test_memory_size() {
let (result_count, answer) = (1u8, 42u8);
let my_val = json_object! {
result_count,
errors: null,
results: json_list![
json_object!{answer, ok: true}
]
};
// my_val weighs only two bytes, because we stored only 2 u8 in it
assert_eq!(2, ::std::mem::size_of_val(&my_val));
}
```
## Performance
This library is generally faster than SERDE.
Here are detailed comparison results on different json serialization tasks realized on an AMD Ryzen 5 1600X.
[See detailed benchmark results.](https://lovasoa.github.io/json_in_type/docs/criterion/report/)
### Encoding 8 nested json objects using a rust macro
We use serde's
[`json!`](https://docs.serde.rs/serde_json/macro.json.html)
and json_in_type's
[`json_object!`](https://docs.rs/json_in_type/latest/json_in_type/macro.json_object.html)
macro to encode a nested json object.
#### Encoded object
We encode a JSON structure composed of 8 nested objects, each of
which contains a single key, that is known at compile time.
The last nested object contains an integer *n* that is not known at compile time.
```js
{"nested":{"nested":{"nested":{"nested":{"nested":{"nested":{"nested":{"nested":{"value":n}}}}}}}}}
```
#### Benchmark result
### Encoding a very simple json object using a rust macro
#### Encoded object
```json
{
"void": null,
"list": [1, 2, 3, 3],
"hello": "world"
}
```
#### Benchmark result
### Encoding a very simple json object using `#[derive(...)]`
#### Encoded object
```json
{
"void": null,
"list": [1, 2, 3, 3],
"hello": "world"
}
```
created from the following rust struct
```rust
#[derive(Serialize, JSONValue)]
struct MyObject {
void: (),
list: Vec,
hello: String,
}
```
#### Benchmark result
## External links
* docs.rs hosts this crate's [api documentation](https://docs.rs/json_in_type).
* documentation for [the `json_object!` macro](https://docs.rs/json_in_type/latest/json_in_type/macro.json_object.html)
* documentation for [the `JSONValue` trait](https://docs.rs/json_in_type/latest/json_in_type/trait.JSONValue.html)
* You can automatically derive the `JSONValue` trait for your type using the [json_in_type_derive crate](https://docs.rs/json_in_type_derive)
* You can see [json_in_type on crates.io](https://crates.io/crates/json_in_type).