# jsonrpc-v2
[](https://docs.rs/jsonrpc-v2/)
[](https://crates.io/crates/jsonrpc-v2)
A very small and very fast JSON-RPC 2.0 server-focused framework.
Provides integrations for both `hyper` and `actix-web` (1.x, 2.x, 3.x, 4.x).
Enable features `actix-web-v3-integration`, `hyper-integration`, etc. as needed.
`actix-web-v4-integration` is enabled by default. Make sure to add `default-features = false` if using `hyper` or other `actix-web` versions.
Also see the `easy-errors` feature flag (not enabled by default). Enabling this flag will implement [`ErrorLike`](https://docs.rs/jsonrpc-v2/*/jsonrpc_v2/trait.ErrorLike.html)
for anything that implements `Display`, and the display value will be provided in the `message` field of the JSON-RPC 2.0 `Error` response.
Otherwise, custom errors should implement [`ErrorLike`](https://docs.rs/jsonrpc-v2/*/jsonrpc_v2/trait.ErrorLike.html) to map errors to the JSON-RPC 2.0 `Error` response.
Individual method handlers are `async` functions that can take various kinds of args (things that can be extracted from the request, like
the `Params` or `Data`), and should return a `Result<Item, Error>` where the `Item` is serializable. See examples below.
## Usage
```rust
use jsonrpc_v2::{Data, Error, Params, Server};
#[derive(serde::Deserialize)]
struct TwoNums {
a: usize,
b: usize,
}
async fn add(Params(params): Params<TwoNums>) -> Result<usize, Error> {
Ok(params.a + params.b)
}
async fn sub(Params(params): Params<(usize, usize)>) -> Result<usize, Error> {
Ok(params.0 - params.1)
}
async fn message(data: Data<String>) -> Result<String, Error> {
Ok(String::from(&*data))
}
#[actix_rt::main]
async fn main() -> std::io::Result<()> {
let rpc = Server::new()
.with_data(Data::new(String::from("Hello!")))
.with_method("sub", sub)
.with_method("message", message)
.finish();
actix_web::HttpServer::new(move || {
let rpc = rpc.clone();
actix_web::App::new().service(
actix_web::web::service("/api")
.guard(actix_web::guard::Post())
.finish(rpc.into_web_service()),
)
})
.bind("0.0.0.0:3000")?
.run()
.await
}
```
Current version: 0.11.0
License: MIT