JSON-RPC 2.0 server implementation in Rust
```rust
fn greet(name: String) -> Result
struct System;
impl System {
fn time() -> Result
async fn issue() -> Result<String, json_rpc_v2::Error> {
read_to_string("/etc/issue").await.map_err(|_| json_rpc_v2::Error::server_error())
}
}
async fn main() -> Result<(), Box
let _ = registry.call(br#"{"jsonrpc":"2.0","method":"greet","params":["foo"],"id":1}"#).await;
let _ = registry.call(br#"{"jsonrpc":"2.0","method":"system.time","params":[],"id":1}"#).await;
let _ = registry.call(br#"{"jsonrpc":"2.0","method":"system.issue","params":[],"id":1}"#).await;
Ok(())
} ```