v0.3.0

[0.3.0] - 2026-02-19

Breaking Changes

Major Architecture Change: Bring Your Own Transport

The library has been refactored from a full server implementation with built-in
transports to a "Bring Your Own Transport" handler pattern. This simplifies the
library and makes it more flexible and framework-agnostic.

API Changes:

• Methods renamed to JsonRpc and moved to src/jsonrpc.rs
• serve() function removed - users now call JsonRpc::call() directly
• All built-in transports removed from the library:
  • Stdio transport removed
  • Http transport removed
  • InMemory transport removed
  • Transport trait removed
• Error::TransportError variant removed - transport I/O errors should be
  handled by user's transport code
• Error::Cancelled variant removed - cancellation handled by transport layer
• Error::transport() constructor method removed
• Default impl for JsonRpc removed - use JsonRpc::new() instead
• axum integration is now optional (enable with features = ["axum"])

Migration Guide:

Old server-based API:

use json_rpc::{Methods, Stdio};

let methods = Methods::new().add("echo", echo);
let transport = Stdio::new();
json_rpc::serve(transport, methods).await?;

New handler-based API:

use json_rpc::JsonRpc;

let json_rpc = JsonRpc::new().add("echo", echo);
let stdin = tokio::io::stdin();
let mut reader = tokio::io::BufReader::new(stdin);
let mut line = String::new();

while reader.read_line(&mut line).await? > 0 {
    let trimmed = line.trim();
    if !trimmed.is_empty() {
        if let Some(response) = json_rpc.call(trimmed).await {
            println!("{}", response);
        }
    }
    line.clear();
}

For HTTP integration with axum:

use axum::{Router, routing::post};
use json_rpc::{JsonRpc, axum::handler};
use std::sync::Arc;

let json_rpc = JsonRpc::new().add("echo", echo);
let app = Router::new()
    .route("/jsonrpc", post(handler))
    .with_state(Arc::new(json_rpc));
let listener = tokio::net::TcpListener::bind(addr).await?;
axum::serve(listener, app).await?;

Changed

• Simplify from_json parsing logic with modular helper functions
• Add axum handler in src/axum.rs for HTTP integration
• Make axum and http dependencies optional with new feature flags
• Update Cargo.toml metadata and description
• Update documentation throughout codebase to reflect handler pattern

Fixed

• Fix version number in README.md