golang rpc的两种调用方法
golang的rpc有两种方法进行调用,一种是rpc例子中给的:
package main import ( "net/rpc" "net/http" "log" "net" "time" ) type Args struct { A, B int } type Arith int func (t *Arith) Multiply(args *Args, reply *([]string)) error { *reply = append(*reply, "test") return nil } func main() { arith := new(Arith) rpc.Register(arith) rpc.HandleHTTP() l, e := net.Listen("tcp", ":1234") if e != nil { log.Fatal("listen error:", e) } go http.Serve(l, nil) time.Sleep(5 * time.Second) client, err := rpc.DialHTTP("tcp", "127.0.0.1" + ":1234") if err != nil { log.Fatal("dialing:", err) } args := &Args{7,8} reply := make([]string, 10) err = client.Call("Arith.Multiply", args, &reply) if err != nil { log.Fatal("arith error:", err) } log.Println(reply) }
另一种是使用NewServer
这种是当rpc已经注册的时候就要使用了另外一种了。即一个server只能在DefaultRPC中注册一种类型。
当Server使用rpc.NewServer的时候,client也需要进行下改动了
package main import ( "net/rpc" //"net/http" "log" "net" "time" ) type Args struct { A, B int } type Arith int func (t *Arith) Multiply(args *Args, reply *([]string)) error { *reply = append(*reply, "test") return nil } func main() { newServer := rpc.NewServer() newServer.Register(new(Arith)) l, e := net.Listen("tcp", "127.0.0.1:1234") // any available address if e != nil { log.Fatalf("net.Listen tcp :0: %v", e) } go newServer.Accept(l) newServer.HandleHTTP("/foo", "/bar") time.Sleep(2 * time.Second) address, err := net.ResolveTCPAddr("tcp", "127.0.0.1:1234") if err != nil { panic(err) } conn, _ := net.DialTCP("tcp", nil, address) defer conn.Close() client := rpc.NewClient(conn) defer client.Close() args := &Args{7,8} reply := make([]string, 10) err = client.Call("Arith.Multiply", args, &reply) if err != nil { log.Fatal("arith error:", err) } log.Println(reply) }
第二个例子中的
newServer.HandleHTTP("/foo", "/bar")
可以任意设置,第一个例子其实是设置了默认的两个
1
1
这里也顺便将reply作为[]slice的例子给演示了下