Use of the Go language net package RPC Remote Call

One, HTTP-based RPC

Service side:

Package Main;import ("Net/rpc" "Net/http" "Log")//go support for RPC, supports three levels: TCP, HTTP, jsonrpc//go RPC only supports the interaction between the server and client of Go development, Because the GOB encoding//Note field must be exported type Params struct {Width, Height int;} The type Rect struct{}//function must be exported//must have two export type parameters//The first parameter is the receive parameter//the second parameter is returned to the client parameter, must be a pointer type//function and have a return value Errorfunc (r *rect) area (p Params, ret *int) error {*ret = P.width * P.height;return nil;} Func (R *rect) Perimeter (P Params, ret *int) error {*ret = (p.width + p.height) * 2;return Nil;} Func Main () {rect: = new (rect);//registers a RECT service RPC. Register (rect);//BIND service processing to RPC on HTTP protocol. Handlehttp (); Err: = http. Listenandserve (": 8080", nil); if err! = Nil {log. Fatal (err);}}

Client:

Package Main;import ("Net/rpc" "Log" "FMT") type Params struct {Width, Height int;} Func Main () {///Connect the remote RPC service RPC, err: = RPC. Dialhttp ("TCP", "127.0.0.1:8080"); if err! = Nil {log. Fatal (err);} RET: = 0;//Call remote method//Note The third parameter is pointer type err2: = RPC. Call ("Rect.area", params{50, +, &ret); if err2! = Nil {log. Fatal (ERR2);} Fmt. PRINTLN (ret); ERR3: = RPC. Call ("Rect.perimeter", params{50, +, &ret); if err3! = Nil {log. Fatal (ERR3);} Fmt. PRINTLN (ret);}

Second, TCP-based RPC

Service side:

Package Main;import ("NET" "Log" "NET/RPC")//note field must be exported type Params struct {Width, Height int;} Type Rect Struct{}func (r *rect) area (P Params, ret *int) error {*ret = P.width * P.height;return nil;} Func (R *rect) Perimeter (P Params, ret *int) error {*ret = (p.width + p.height) * 2;return Nil;} Func chkerror (err error) {if err! = Nil {log. Fatal (err);}} Func Main () {rect: = new (rect);//register RPC service RPC. Register (rect);//Get tcpaddrtcpaddr, err: = Net. RESOLVETCPADDR ("TCP4", "127.0.0.1:8080"); Chkerror (err);//Listener Port Tcplisten, ERR2: = Net. LISTENTCP ("TCP", tcpaddr); Chkerror (ERR2);//Dead Loop processing connection request for {conn, err3: = Tcplisten. Accept (); if err3! = nil {continue;} Use Goroutine to handle RPC connection requests alone to go RPC. SERVECONN (conn);}}

Client:

Package Main;import ("Net/rpc" "FMT" "Log") type Params struct {Width, Height int;} Func Main () {///connect to the remote RPC Service///use dialhttp here, the other code is the same as RPC, err: = RPC. Dial,http. Dial ("TCP", "127.0.0.1:8080"); if err! = Nil {log. Fatal (err);} RET: = 0;//Call remote method//Note The third parameter is pointer type err2: = RPC. Call ("Rect.area", params{50, +, &ret); if err2! = Nil {log. Fatal (ERR2);} Fmt. PRINTLN (ret); ERR3: = RPC. Call ("Rect.perimeter", params{50, +, &ret); if err3! = Nil {log. Fatal (ERR3);} Fmt. PRINTLN (ret);}

Third, the JSON RPC way

The Jsonrpc method is that the data is encoded using JSON rather than GOB encoding.

Service side:

Package Main;import ("NET" "Log" "Net/rpc" "NET/RPC/JSONRPC")//note field must be exported type Params struct {Width, Height int;} Type Rect Struct{}func (r *rect) area (P Params, ret *int) error {*ret = P.width * P.height;return nil;} Func (R *rect) Perimeter (P Params, ret *int) error {*ret = (p.width + p.height) * 2;return Nil;} Func chkerror (err error) {if err! = Nil {log. Fatal (err);}} Func Main () {rect: = new (rect);//register RPC service RPC. Register (rect);//Get tcpaddrtcpaddr, err: = Net. RESOLVETCPADDR ("TCP4", "127.0.0.1:8080"); Chkerror (err);//Listener Port Tcplisten, ERR2: = Net. LISTENTCP ("TCP", tcpaddr); Chkerror (ERR2); for {conn, err3: = Tcplisten. Accept (); if err3! = nil {continue;} Use Goroutine to process RPC connection requests separately//use JSONRPC to process go jsonrpc here. SERVECONN (conn);}}

Client:

Package Main;import ("FMT" "Log" "Net/rpc/jsonrpc") type Params struct {Width, Height int;} Func Main () {///connect to the remote RPC service//use JSONRPC here. DIALRPC, err: = Jsonrpc. Dial ("TCP", "127.0.0.1:8080"); if err! = Nil {log. Fatal (err);} RET: = 0;//Call remote method//Note The third parameter is pointer type err2: = RPC. Call ("Rect.area", params{50, +, &ret); if err2! = Nil {log. Fatal (ERR2);} Fmt. PRINTLN (ret); ERR3: = RPC. Call ("Rect.perimeter", params{50, +, &ret); if err3! = Nil {log. Fatal (ERR3);} Fmt. PRINTLN (ret);}

Use of the Go language net package RPC Remote Call