Websocket
WebSocket is a protocol that enables two-way persistent communication channels over TCP connections. It is used for applications such as chat, stock tickers, games, anywhere you want real-time functionality in a web application.
View or download sample code.
When to use it
Use WebSockets when you need to work directly with a socket connection. For example, you might need the best possible performance for a real-time game.
How to use it
- import the
"github.com/kataras/iris/websocket"
- Configure the websocket package.
- Accept WebSocket requests.
- Send and receive messages.
Import the websocket package
import "github.com/kataras/iris/websocket"
import "github.com/kataras/iris/websocket"
func main() {
ws := websocket.New(websocket.Config{
ReadBufferSize: 1024,
WriteBufferSize: 1024,
})
}
Complete configuration
// Config the websocket server configuration
// all of these are optional.
type Config struct {
// IDGenerator used to create (and later on, set)
// an ID for each incoming websocket connections (clients).
// The request is an argument which you can use to generate the ID (from headers for example).
// If empty then the ID is generated by DefaultIDGenerator: randomString(64)
IDGenerator func(ctx context.Context) string
Error func(w http.ResponseWriter, r *http.Request, status int, reason error)
CheckOrigin func(r *http.Request) bool
// HandshakeTimeout specifies the duration for the handshake to complete.
HandshakeTimeout time.Duration
// WriteTimeout time allowed to write a message to the connection.
// 0 means no timeout.
// Default value is 0
WriteTimeout time.Duration
// ReadTimeout time allowed to read a message from the connection.
// 0 means no timeout.
// Default value is 0
ReadTimeout time.Duration
// PongTimeout allowed to read the next pong message from the connection.
// Default value is 60 * time.Second
PongTimeout time.Duration
// PingPeriod send ping messages to the connection with this period. Must be less than PongTimeout.
// Default value is 60 *time.Second
PingPeriod time.Duration
// MaxMessageSize max message size allowed from connection.
// Default value is 1024
MaxMessageSize int64
// BinaryMessages set it to true in order to denotes binary data messages instead of utf-8 text
// compatible if you wanna use the Connection's EmitMessage to send a custom binary data to the client, like a native server-client communication.
// defaults to false
BinaryMessages bool
// ReadBufferSize is the buffer size for the underline reader
// Default value is 4096
ReadBufferSize int
// WriteBufferSize is the buffer size for the underline writer
// Default value is 4096
WriteBufferSize int
// EnableCompression specify if the server should attempt to negotiate per
// message compression (RFC 7692). Setting this value to true does not
// guarantee that compression will be supported. Currently only "no context
// takeover" modes are supported.
EnableCompression bool
// Subprotocols specifies the server's supported protocols in order of
// preference. If this field is set, then the Upgrade method negotiates a
// subprotocol by selecting the first match in this list with a protocol
// requested by the client.
Subprotocols []string
}
Accept WebSocket requests & send & receive messages
import (
"github.com/kataras/iris"
"github.com/kataras/iris/websocket"
)
func main() {
ws := websocket.New(websocket.Config{
ReadBufferSize: 1024,
WriteBufferSize: 1024,
})
ws.OnConnection(handleConnection)
app := iris.New()
// register the server on an endpoint.
// see the inline javascript code in the websockets.html, this endpoint is used to connect to the server.
app.Get("/echo", ws.Handler())
// serve the javascript built'n client-side library,
// see weboskcets.html script tags, this path is used.
app.Any("/iris-ws.js", func(ctx iris.Context) {
ctx.Write(websocket.ClientSource)
})
}
func handleConnection(c websocket.Connection) {
// Read events from browser
c.On("chat", func(msg string) {
// Print the message to the console, c.Context() is the iris's http context.
fmt.Printf("%s sent: %s\n", c.Context().RemoteAddr(), msg)
// Write message back to the client message owner:
// c.Emit("chat", msg)
c.To(websocket.Broadcast).Emit("chat", msg)
})
}