jsonrpc2

Package jsonrpc2 is an implementation of the JSON-RPC 2 specification for Go.

Features Comparison

This library is a fork of go.lsp.dev/jsonrpc2, which itself is a cleaned-up fork of x/tools/internal/jsonrpc2. The goal is to provide an importable, stdlib-only JSON-RPC 2 library that cherry-picks the best ideas from the Go team's v2 rewrite without the complexity.

Feature	kwo/jsonrpc2	go.lsp.dev/jsonrpc2	x/tools jsonrpc2 (v1)	x/tools jsonrpc2_v2
Importable	✅	✅	❌ internal	❌ internal
Stdlib only (no external deps)	✅	❌ segmentio/encoding	❌ internal/event	✅
LOC (Go, non-test)	1,460	1,533	1,833	1,859
LSP header framing	✅	✅	✅	✅
Raw JSON framing	✅	✅	✅	✅
Bidirectional Conn	✅	✅	✅	✅
Call / Notify / Response messages	✅	✅	✅	✅
Structured JSON-RPC error codes	✅	✅	✅	✅
Context cancellation	✅	✅	✅	✅
Server idle timeout	✅	✅	✅	✅
Split Reader/Writer interfaces	✅	—	—	✅
AsyncCall (non-blocking Call)	✅	—	—	✅
Write error propagation	✅	—	—	✅
Handler returns (result, error)	✅	—	—	✅
Graceful close (drain in-flight)	—	—	—	✅
Server.Shutdown (graceful stop)	—	—	—	✅
CancelHandler	✅	✅	✅	—
AsyncHandler	✅	✅	✅	—
StreamServer / Serve / ListenAndServe	✅	✅	✅	—
Test helpers (TCP + pipe servers)	✅	✅	✅	—
ReplyHandler (must-reply enforcement)	—	✅	✅	—
Binder (per-connection config)	—	—	—	✅
Preempter (pre-queue handling)	—	—	—	✅
ErrAsyncResponse (deferred replies)	—	—	—	✅
IdleListener with finalizers	—	—	—	✅
Built-in event tracing/metrics	—	—	✅	—
Listener/Dialer interfaces	—	—	—	✅

LOC note: counts are approximate Go source lines for each implementation, excluding *_test.go. For x/tools, counts are for the internal/jsonrpc2 and internal/jsonrpc2_v2 directories only.

References

• JSON-RPC 2.0 Specification
• golang.org/x/tools/internal/jsonrpc2
• github.com/sourcegraph/jsonrpc2

OpenRPC

The OpenRPC Specification defines a standard, programming language-agnostic interface description for JSON-RPC 2.0 APIs.

• open-rpc.org
• OpenRPC Specification
• OpenRPC GitHub organization