Calling the JSON-RPC service

This recipe will illustrate how procedures via the JSON-RPC protocol can be called with use of the standard library.

How to do it...

1. Open the console and create the folder chapter07/recipe11.
2. Navigate to the directory.
3. Create the jsonrpc.go file with the following content:

        package main

        import (
          "log"
          "net"
          "net/rpc"
          "net/rpc/jsonrpc"
        )

        type Args struct {
          A, B int
        }

        type Result int

        type RpcServer struct{}

        func (t RpcServer) Add(args *Args, result *Result) error {
          log.Printf("Adding %d to %d\n", args.A, args.B)
          *result = Result(args.A + args.B)
          return nil
        } 

        const addr = ":7070"

        func main() {
          go createServer(addr)
          client, err := jsonrpc.Dial("tcp", addr)
          if err != nil {
            panic(err)
          }
          defer client.Close()
          args := &Args{
...