gev

README

gev

中文 | English

gev is a lightweight, fast non-blocking TCP network library / websocket server based on Reactor mode.

Support custom protocols to quickly and easily build high-performance servers.

Features

• High-performance event loop based on epoll and kqueue
• Support multi-core and multi-threading
• Dynamic expansion of read and write buffers implemented by Ring Buffer
• Asynchronous read and write
• SO_REUSEPORT port reuse support
• Automatically clean up idle connections
• Support WebSocket/Protobuf, custom protocols
• Support for scheduled tasks, delayed tasks
• High performance websocket server

Network model

gev uses only a few goroutines, one of them listens for connections and the others (work coroutines) handle read and write events of connected clients. The count of work coroutines is configurable, which is the core number of host CPUs by default.

Performance Test

📈 Test chart

Test environment: Ubuntu18.04 | 4 Virtual CPUs | 4.0 GiB

Throughput Test

limit GOMAXPROCS=1（Single thread），1 work goroutine

limit GOMAXPROCS=4，4 work goroutine

Other Test

Speed ​​Test

Compared with the simple performance of similar libraries, the pressure measurement method is the same as the evio project.

• gnet
• eviop
• evio
• net (StdLib)

limit GOMAXPROCS=1，1 work goroutine

limit GOMAXPROCS=1，4 work goroutine

limit GOMAXPROCS=4，4 work goroutine

Install

go get -u github.com/Allenxuxu/gev

Getting start

echo demo

package main

import (
	"flag"
	"strconv"

	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
)

type example struct{}

func (s *example) OnConnect(c *connection.Connection) {
	//log.Println(" OnConnect ： ", c.PeerAddr())
}
func (s *example) OnMessage(c *connection.Connection, ctx interface{}, data []byte) (out []byte) {
	//log.Println("OnMessage")
	out = data
	return
}

func (s *example) OnClose(c *connection.Connection) {
	//log.Println("OnClose")
}

func main() {
	handler := new(example)
	var port int
	var loops int

	flag.IntVar(&port, "port", 1833, "server port")
	flag.IntVar(&loops, "loops", -1, "num loops")
	flag.Parse()

	s, err := gev.NewServer(handler,
		gev.Address(":"+strconv.Itoa(port)),
		gev.NumLoops(loops))
	if err != nil {
		panic(err)
	}

	s.Start()
}

Handler is an interface that programs must implement.

type Handler interface {
	OnConnect(c *connection.Connection)
	OnMessage(c *connection.Connection, ctx interface{}, data []byte) []byte
	OnClose(c *connection.Connection)
}

func NewServer(handler Handler, opts ...Option) (server *Server, err error)

OnMessage will be called back when a complete data frame arrives.Users can get the data, process the business logic, and return the data that needs to be sent.

When there is data coming, gev does not call back OnMessage immediately, but instead calls back an UnPacket function.Probably the execution logic is as follows:

ctx, receivedData := c.protocol.UnPacket(c, buffer)
	if ctx != nil || len(receivedData) != 0 {
		sendData := c.OnMessage(c, ctx, receivedData)
		if len(sendData) > 0 {
			return c.protocol.Packet(c, sendData)
		}
	}

The UnPacket function will check whether the data in the ringbuffer is a complete data frame. If it is, the data will be unpacked and return the payload data. If it is not a complete data frame, it will return directly.

The return value of UnPacket (interface{}, []byte) will be passed in as a call to OnMessage ctx interface{}, data []byte and callback.Ctx is designed to pass special information generated when parsing data frames in the UnPacket function (which is required for complex data frame protocols), and data is used to pass payload data.

type Protocol interface {
	UnPacket(c *Connection, buffer *ringbuffer.RingBuffer) (interface{}, []byte)
	Packet(c *Connection, data []byte) []byte
}

type DefaultProtocol struct{}

func (d *DefaultProtocol) UnPacket(c *Connection, buffer *ringbuffer.RingBuffer) (interface{}, []byte) {
	ret := buffer.Bytes()
	buffer.RetrieveAll()
	return nil, ret
}

func (d *DefaultProtocol) Packet(c *Connection, data []byte) []byte {
	return data
}

As above, gev provides a default Protocol implementation that will fetch all data in the receive buffer ( ringbuffer ).In actual use, there is usually a data frame protocol of its own, and gev can be set in the form of a plug-in: it is set by variable parameters when creating Server.

s, err := gev.NewServer(handler,gev.Protocol(&ExampleProtocol{}))

Check out the example Protocol for a detailed.

There is also a Send method that can be used for sending data. But Send puts the data to Event-Loop and invokes it to send the data rather than sending data by itself immediately.

Check out the example Server timing push for a detailed.

func (c *Connection) Send(buffer []byte) error

ShutdownWrite works for reverting connected status to false and closing connection.

Check out the example Maximum connections for a detailed.

func (c *Connection) ShutdownWrite() error

RingBuffer is a dynamical expansion implementation of circular buffer.

WebSocket

The WebSocket protocol is built on top of the TCP protocol, so gev doesn't need to be built in, but instead provides support in the form of plugins, in the plugins/websocket directory.

code

type Protocol struct {
	upgrade *ws.Upgrader
}

func New(u *ws.Upgrader) *Protocol {
	return &Protocol{upgrade: u}
}

func (p *Protocol) UnPacket(c *connection.Connection, buffer *ringbuffer.RingBuffer) (ctx interface{}, out []byte) {
	upgraded := c.Context()
	if upgraded == nil {
		var err error
		out, _, err = p.upgrade.Upgrade(buffer)
		if err != nil {
			log.Println("Websocket Upgrade :", err)
			return
		}
		c.SetContext(true)
	} else {
		header, err := ws.VirtualReadHeader(buffer)
		if err != nil {
			log.Println(err)
			return
		}
		if buffer.VirtualLength() >= int(header.Length) {
			buffer.VirtualFlush()

			payload := make([]byte, int(header.Length))
			_, _ = buffer.Read(payload)

			if header.Masked {
				ws.Cipher(payload, header.Mask, 0)
			}

			ctx = &header
			out = payload
		} else {
			buffer.VirtualRevert()
		}
	}
	return
}

func (p *Protocol) Packet(c *connection.Connection, data []byte) []byte {
	return data
}

The detailed implementation can be viewed by the plugin. The source code can be viewed using the websocket example.

Example

echo server

package main

import (
	"flag"
	"strconv"

	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
)

type example struct{}

func (s *example) OnConnect(c *connection.Connection) {
	//log.Println(" OnConnect ： ", c.PeerAddr())
}
func (s *example) OnMessage(c *connection.Connection, ctx interface{}, data []byte) (out []byte) {
	//log.Println("OnMessage")
	out = data
	return
}

func (s *example) OnClose(c *connection.Connection) {
	//log.Println("OnClose")
}

func main() {
	handler := new(example)
	var port int
	var loops int

	flag.IntVar(&port, "port", 1833, "server port")
	flag.IntVar(&loops, "loops", -1, "num loops")
	flag.Parse()

	s, err := gev.NewServer(handler,
		gev.Network("tcp"),
		gev.Address(":"+strconv.Itoa(port)),
		gev.NumLoops(loops))
	if err != nil {
		panic(err)
	}

	s.Start()
}

Automatically clean up idle connections

package main

import (
	"flag"
	"strconv"
	"time"

	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
	"github.com/Allenxuxu/gev/log"
)

type example struct {
}

func (s *example) OnConnect(c *connection.Connection) {
	log.Info(" OnConnect ： ", c.PeerAddr())
}
func (s *example) OnMessage(c *connection.Connection, ctx interface{}, data []byte) (out []byte) {
	log.Infof("OnMessage from : %s", c.PeerAddr())
	out = data
	return
}

func (s *example) OnClose(c *connection.Connection) {
	log.Info("OnClose: ", c.PeerAddr())
}

func main() {
	handler := new(example)
	var port int
	var loops int

	flag.IntVar(&port, "port", 1833, "server port")
	flag.IntVar(&loops, "loops", -1, "num loops")
	flag.Parse()

	s, err := gev.NewServer(handler,
		gev.Network("tcp"),
		gev.Address(":"+strconv.Itoa(port)),
		gev.NumLoops(loops),
		gev.IdleTime(5*time.Second))
	if err != nil {
		panic(err)
	}

	s.Start()
}

Maximum connections

package main

import (
	"log"

	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
	"github.com/Allenxuxu/toolkit/sync/atomic"
)

// Server example
type Server struct {
	clientNum     atomic.Int64
	maxConnection int64
	server        *gev.Server
}

// New server
func New(ip, port string, maxConnection int64) (*Server, error) {
	var err error
	s := new(Server)
	s.maxConnection = maxConnection
	s.server, err = gev.NewServer(s,
		gev.Address(ip+":"+port))
	if err != nil {
		return nil, err
	}

	return s, nil
}

// Start server
func (s *Server) Start() {
	s.server.Start()
}

// Stop server
func (s *Server) Stop() {
	s.server.Stop()
}

// OnConnect callback
func (s *Server) OnConnect(c *connection.Connection) {
	s.clientNum.Add(1)
	log.Println(" OnConnect ： ", c.PeerAddr())

	if s.clientNum.Get() > s.maxConnection {
		_ = c.ShutdownWrite()
		log.Println("Refused connection")
		return
	}
}

// OnMessage callback
func (s *Server) OnMessage(c *connection.Connection, ctx interface{}, data []byte) (out []byte) {
	log.Println("OnMessage")
	out = data
	return
}

// OnClose callback
func (s *Server) OnClose(c *connection.Connection) {
	s.clientNum.Add(-1)
	log.Println("OnClose")
}

func main() {
	s, err := New("", "1833", 1)
	if err != nil {
		panic(err)
	}
	defer s.Stop()

	s.Start()
}

Server timing push

package main

import (
	"container/list"
	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
	"log"
	"sync"
	"time"
)

// Server example
type Server struct {
	conn   *list.List
	mu     sync.RWMutex
	server *gev.Server
}

// New server
func New(ip, port string) (*Server, error) {
	var err error
	s := new(Server)
	s.conn = list.New()
	s.server, err = gev.NewServer(s,
		gev.Address(ip+":"+port))
	if err != nil {
		return nil, err
	}

	return s, nil
}

// Start server
func (s *Server) Start() {
	s.server.RunEvery(1*time.Second, s.RunPush)
	s.server.Start()
}

// Stop server
func (s *Server) Stop() {
	s.server.Stop()
}

// RunPush push message
func (s *Server) RunPush() {
	var next *list.Element

	s.mu.RLock()
	defer s.mu.RUnlock()

	for e := s.conn.Front(); e != nil; e = next {
		next = e.Next()

		c := e.Value.(*connection.Connection)
		_ = c.Send([]byte("hello\n"))
	}
}

// OnConnect callback
func (s *Server) OnConnect(c *connection.Connection) {
	log.Println(" OnConnect ： ", c.PeerAddr())

	s.mu.Lock()
	e := s.conn.PushBack(c)
	s.mu.Unlock()
	c.SetContext(e)
}

// OnMessage callback
func (s *Server) OnMessage(c *connection.Connection, ctx interface{}, data []byte) (out []byte) {
	log.Println("OnMessage")
	out = data
	return
}

// OnClose callback
func (s *Server) OnClose(c *connection.Connection) {
	log.Println("OnClose")
	e := c.Context().(*list.Element)

	s.mu.Lock()
	s.conn.Remove(e)
	s.mu.Unlock()
}

func main() {
	s, err := New("", "1833")
	if err != nil {
		panic(err)
	}
	defer s.Stop()

	s.Start()
}

WebSocket

package main

import (
	"flag"
	"log"
	"math/rand"
	"strconv"

	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
	"github.com/Allenxuxu/gev/plugins/websocket/ws"
	"github.com/Allenxuxu/gev/plugins/websocket/ws/util"
)

type example struct{}

func (s *example) OnConnect(c *connection.Connection) {
	log.Println(" OnConnect ： ", c.PeerAddr())
}
func (s *example) OnMessage(c *connection.Connection, data []byte) (messageType ws.MessageType, out []byte) {
	log.Println("OnMessage:", string(data))
	messageType = ws.MessageBinary
	switch rand.Int() % 3 {
	case 0:
		out = data
	case 1:
		msg, err := util.PackData(ws.MessageText, data)
		if err != nil {
			panic(err)
		}
		if err := c.Send(msg); err != nil {
			msg, err := util.PackCloseData(err.Error())
			if err != nil {
				panic(err)
			}
			if e := c.Send(msg); e != nil {
				panic(e)
			}
		}
	case 2:
		msg, err := util.PackCloseData("close")
		if err != nil {
			panic(err)
		}
		if e := c.Send(msg); e != nil {
			panic(e)
		}
	}
	return
}

func (s *example) OnClose(c *connection.Connection) {
	log.Println("OnClose")
}

func main() {
	handler := new(example)
	var port int
	var loops int

	flag.IntVar(&port, "port", 1833, "server port")
	flag.IntVar(&loops, "loops", -1, "num loops")
	flag.Parse()

	s, err := NewWebSocketServer(handler, &ws.Upgrader{},
		gev.Network("tcp"),
		gev.Address(":"+strconv.Itoa(port)),
		gev.NumLoops(loops))
	if err != nil {
		panic(err)
	}

	s.Start()
}

package main

import (
	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/plugins/websocket"
	"github.com/Allenxuxu/gev/plugins/websocket/ws"
)

// NewWebSocketServer 创建 WebSocket Server
func NewWebSocketServer(handler websocket.WebSocketHandler, u *ws.Upgrader, opts ...gev.Option) (server *gev.Server, err error) {
	opts = append(opts, gev.Protocol(websocket.New(u)))
	return gev.NewServer(websocket.NewHandlerWrap(u, handler), opts...)
}

protobuf

package main

import (
	"flag"
	"log"
	"strconv"

	"github.com/Allenxuxu/gev"
	"github.com/Allenxuxu/gev/connection"
	pb "github.com/Allenxuxu/gev/example/protobuf/proto"
	"github.com/Allenxuxu/gev/plugins/protobuf"
	"google.golang.org/protobuf/proto"
)

type example struct{}

func (s *example) OnConnect(c *connection.Connection) {
	log.Println(" OnConnect ： ", c.PeerAddr())
}
func (s *example) OnMessage(c *connection.Connection, ctx interface{}, data []byte) (out []byte) {
	msgType := ctx.(string)

	switch msgType {
	case "msg1":
		msg := &pb.Msg1{}
		if err := proto.Unmarshal(data, msg); err != nil {
			log.Println(err)
		}
		log.Println(msgType, msg)
	case "msg2":
		msg := &pb.Msg2{}
		if err := proto.Unmarshal(data, msg); err != nil {
			log.Println(err)
		}
		log.Println(msgType, msg)
	default:
		log.Println("unknown msg type")
	}

	return
}

func (s *example) OnClose(c *connection.Connection) {
	log.Println("OnClose")
}

func main() {
	handler := new(example)
	var port int
	var loops int

	flag.IntVar(&port, "port", 1833, "server port")
	flag.IntVar(&loops, "loops", -1, "num loops")
	flag.Parse()

	s, err := gev.NewServer(handler,
		gev.Network("tcp"),
		gev.Address(":"+strconv.Itoa(port)),
		gev.NumLoops(loops),
		gev.Protocol(&protobuf.Protocol{}))
	if err != nil {
		panic(err)
	}

	log.Println("server start")
	s.Start()
}

package main

import (
	"bufio"
	"fmt"
	"log"
	"math/rand"
	"net"
	"os"

	pb "github.com/Allenxuxu/gev/example/protobuf/proto"
	"github.com/Allenxuxu/gev/plugins/protobuf"
	"google.golang.org/protobuf/proto"
)

func main() {
	conn, e := net.Dial("tcp", ":1833")
	if e != nil {
		log.Fatal(e)
	}
	defer conn.Close()

	var buffer []byte
	for {
		reader := bufio.NewReader(os.Stdin)
		fmt.Print("Text to send: ")
		text, _ := reader.ReadString('\n')
		name := text[:len(text)-1]

		switch rand.Int() % 2 {
		case 0:
			msg := &pb.Msg1{
				Name: name,
				Id:   1,
			}

			data, err := proto.Marshal(msg)
			if err != nil {
				panic(err)
			}
			buffer = protobuf.PackMessage("msg1", data)
		case 1:
			msg := &pb.Msg2{
				Name:  name,
				Alias: "big " + name,
				Id:    2,
			}

			data, err := proto.Marshal(msg)
			if err != nil {
				panic(err)
			}
			buffer = protobuf.PackMessage("msg2", data)
		}

		_, err := conn.Write(buffer)
		if err != nil {
			panic(err)
		}
	}
}

Thanks

Thanks JetBrains for the free open source license

References

• evio
• muduo

Documentation

Index

• type Handler
• type LoadBalanceStrategy
  • func LeastConnection() LoadBalanceStrategy
  • func RoundRobin() LoadBalanceStrategy
• type Option
  • func Address(a string) Option
  • func IdleTime(t time.Duration) Option
  • func LoadBalance(strategy LoadBalanceStrategy) Option
  • func MetricsServer(path, address string) Option
  • func Network(n string) Option
  • func NumLoops(n int) Option
  • func Protocol(p connection.Protocol) Option
  • func ReusePort(reusePort bool) Option
• type Options
• type Server
  • func NewServer(handler Handler, opts ...Option) (server *Server, err error)
  • func (s *Server) Options() Options
  • func (s *Server) RunAfter(d time.Duration, f func()) *timingwheel.Timer
  • func (s *Server) RunEvery(d time.Duration, f func()) *timingwheel.Timer
  • func (s *Server) Start()
  • func (s *Server) Stop()

Examples

• Server.RunAfter
• Server.RunEvery

Types

type Handler

type Handler interface {
	connection.CallBack
	OnConnect(c *connection.Connection)
}

Handler Server 注册接口

type LoadBalanceStrategy

type LoadBalanceStrategy func([]*eventloop.EventLoop) *eventloop.EventLoop

func LeastConnection

func LeastConnection() LoadBalanceStrategy

func RoundRobin

func RoundRobin() LoadBalanceStrategy

type Option

type Option func(*Options)

Option ...

func Address

func Address(a string) Option

Address server 监听地址

func IdleTime

func IdleTime(t time.Duration) Option

IdleTime 最大空闲时间（秒）

func LoadBalance

func LoadBalance(strategy LoadBalanceStrategy) Option

func MetricsServer

func MetricsServer(path, address string) Option

func Network

func Network(n string) Option

Network [tcp] 暂时只支持tcp

func NumLoops

func NumLoops(n int) Option

NumLoops work eventloop 的数量

func Protocol

func Protocol(p connection.Protocol) Option

Protocol 数据包处理

func ReusePort

func ReusePort(reusePort bool) Option

ReusePort 设置 SO_REUSEPORT

type Options

type Options struct {
	Network   string
	Address   string
	NumLoops  int
	ReusePort bool
	IdleTime  time.Duration
	Protocol  connection.Protocol
	Strategy  LoadBalanceStrategy
	// contains filtered or unexported fields
}

Options 服务配置

type Server

type Server struct {
	// contains filtered or unexported fields
}

Server gev Server

func NewServer

func NewServer(handler Handler, opts ...Option) (server *Server, err error)

NewServer 创建 Server

func (*Server) Options

func (s *Server) Options() Options

Options 返回 options

func (*Server) RunAfter

func (s *Server) RunAfter(d time.Duration, f func()) *timingwheel.Timer

RunAfter 延时任务

Example

handler := new(example)

s, err := NewServer(handler,
	Network("tcp"),
	Address(":1833"),
	NumLoops(8),
	ReusePort(true))
if err != nil {
	panic(err)
}

go s.Start()
defer s.Stop()

s.RunAfter(time.Second, func() {
	fmt.Println("RunAfter")
})

time.Sleep(2500 * time.Millisecond)

Output:

RunAfter

func (*Server) RunEvery

func (s *Server) RunEvery(d time.Duration, f func()) *timingwheel.Timer

RunEvery 定时任务

Example

handler := new(example)

s, err := NewServer(handler,
	Network("tcp"),
	Address(":1833"),
	NumLoops(8),
	ReusePort(true))
if err != nil {
	panic(err)
}

go s.Start()
defer s.Stop()

t := s.RunEvery(time.Second, func() {
	fmt.Println("EveryFunc")
})

time.Sleep(4500 * time.Millisecond)
t.Stop()
time.Sleep(4500 * time.Millisecond)

Output:

EveryFunc
EveryFunc
EveryFunc
EveryFunc

func (*Server) Start

func (s *Server) Start()

Start 启动 Server

func (*Server) Stop

func (s *Server) Stop()

Stop 关闭 Server