JSON-RPC 2.0

❗️ Main repo: https://gitrepo.ru/neonxp/jsonrpc2. Github is only mirror.

Golang implementation of JSON-RPC 2.0 server with generics.

Go 1.18+ required

Features:

• HTTP/HTTPS transport
• TCP transport
• WebSocket transport

Usage (http transport)

1. Create JSON-RPC server with options:

    import "go.neonxp.ru/jsonrpc2/rpc"
    ...
    s := rpc.New(
        rpc.WithTransport(&transport.HTTP{
            Bind: ":8000",      // Port to bind
            CORSOrigin: "*",    // CORS origin
            TLS: &tls.Config{}, // Optional TLS config (default nil)
            Parallel: true,     // Allow parallel run batch methods (default false)
        }),
        //Other options like transports/middlewares...
    )

2. Add required transport(s):

    import "go.neonxp.ru/jsonrpc2/transport"
    ...
    s.Use(
        rpc.WithTransport(&transport.TCP{Bind: ":3000"}),
        //...
    )

3. Write handlers:

    // This handler supports request parameters
    func Multiply(ctx context.Context, args *Args) (int, error) {
        return args.A * args.B, nil
    }

    // This handler has no request parameters
    func Hello(ctx context.Context) (string, error) {
        return "World", nil
    }

A handler must have a context as first parameter and may have a second parameter, representing request paramters (input of any json serializable type). A handler always returns exactly two values (output of any json serializable type and error).

4. Wrap the handler using one of the two functions rpc.H (supporting req params) or rpc.HS (no params) and register it with the server:

    // handler has params
    s.Register("multiply", rpc.H(Multiply))

    // handler has no params
    s.Register("hello", rpc.HS(Hello))

5. Run RPC server:

    s.Run(ctx)

Custom transport

Any transport must implement simple interface transport.Transport:

type Transport interface {
	Run(ctx context.Context, resolver Resolver) error
}

Complete example

Full code

package main

import (
   "context"

   "go.neonxp.ru/jsonrpc2/rpc"
   "go.neonxp.ru/jsonrpc2/rpc/middleware"
   "go.neonxp.ru/jsonrpc2/transport"
)

func main() {
    s := rpc.New(
        rpc.WithLogger(rpc.StdLogger), // Optional logger
        rpc.WithTransport(&transport.HTTP{Bind: ":8000"}), // HTTP transport
    )

    // Set options after constructor
    s.Use(
        rpc.WithTransport(&transport.TCP{Bind: ":3000"}), // TCP transport
        rpc.WithMiddleware(middleware.Logger(rpc.StdLogger)), // Logger middleware
    )

   s.Register("multiply", rpc.H(Multiply))
   s.Register("divide", rpc.H(Divide))
   s.Register("hello", rpc.HS(Hello))

   s.Run(context.Background())
}

func Multiply(ctx context.Context, args *Args) (int, error) {
    //...
}

func Divide(ctx context.Context, args *Args) (*Quotient, error) {
    //...
}

func Hello(ctx context.Context) (string, error) {
	// ...
}

type Args struct {
	A int `json:"a"`
	B int `json:"b"`
}

type Quotient struct {
	Quo int `json:"quo"`
	Rem int `json:"rem"`
}

Author

Alexander Kiryukhin i@neonxp.dev

License