Implement the websocket adaptor, a version of kataras/go-websocket, and refactor all of the previous websocket examples.

https://github.com/kataras/go-websocket/issues/27

Former-commit-id: 0b7e52e0a61150a8bba973ef653986d8b3ddd26b

adaptors/websocket/config.go

@@ -0,0 +1,136 @@
+package websocket
+
+import (
+	"net/http"
+	"time"
+
+	"gopkg.in/kataras/iris.v6"
+)
+
+const (
+	// DefaultWebsocketWriteTimeout 0, no timeout
+	DefaultWebsocketWriteTimeout = 0
+	// DefaultWebsocketReadTimeout 0, no timeout
+	DefaultWebsocketReadTimeout = 0
+	// DefaultWebsocketPongTimeout 60 * time.Second
+	DefaultWebsocketPongTimeout = 60 * time.Second
+	// DefaultWebsocketPingPeriod (DefaultPongTimeout * 9) / 10
+	DefaultWebsocketPingPeriod = (DefaultWebsocketPongTimeout * 9) / 10
+	// DefaultWebsocketMaxMessageSize 1024
+	DefaultWebsocketMaxMessageSize = 1024
+	// DefaultWebsocketReadBufferSize 4096
+	DefaultWebsocketReadBufferSize = 4096
+	// DefaultWebsocketWriterBufferSize 4096
+	DefaultWebsocketWriterBufferSize = 4096
+	// DefaultClientSourcePath "/iris-ws.js"
+	DefaultClientSourcePath = "/iris-ws.js"
+)
+
+var (
+	// DefaultIDGenerator returns the result of 64
+	// random combined characters as the id of a new connection.
+	// Used when config.IDGenerator is nil
+	DefaultIDGenerator = func(*iris.Context) string { return randomString(64) }
+)
+
+// Config the websocket server configuration
+// all of these are optional.
+type Config struct {
+	// Endpoint is the path which the websocket server will listen for clients/connections
+	// Default value is empty string, if you don't set it the Websocket server is disabled.
+	Endpoint string
+	// ClientSourcePath is is the path which the client-side
+	// will be auto-served when the server adapted to an Iris station.
+	// Default value is "/iris-ws.js"
+	ClientSourcePath string
+	Error            func(w http.ResponseWriter, r *http.Request, status int, reason error)
+	CheckOrigin      func(r *http.Request) bool
+	// 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
+	// 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 *iris.Context) string
+}
+
+// Validate validates the configuration
+func (c Config) Validate() Config {
+
+	if c.ClientSourcePath == "" {
+		c.ClientSourcePath = DefaultClientSourcePath
+	}
+
+	// 0 means no timeout.
+	if c.WriteTimeout < 0 {
+		c.WriteTimeout = DefaultWebsocketWriteTimeout
+	}
+
+	if c.ReadTimeout < 0 {
+		c.ReadTimeout = DefaultWebsocketReadTimeout
+	}
+
+	if c.PongTimeout < 0 {
+		c.PongTimeout = DefaultWebsocketPongTimeout
+	}
+
+	if c.PingPeriod <= 0 {
+		c.PingPeriod = DefaultWebsocketPingPeriod
+	}
+
+	if c.MaxMessageSize <= 0 {
+		c.MaxMessageSize = DefaultWebsocketMaxMessageSize
+	}
+
+	if c.ReadBufferSize <= 0 {
+		c.ReadBufferSize = DefaultWebsocketReadBufferSize
+	}
+
+	if c.WriteBufferSize <= 0 {
+		c.WriteBufferSize = DefaultWebsocketWriterBufferSize
+	}
+
+	if c.Error == nil {
+		c.Error = func(w http.ResponseWriter, r *http.Request, status int, reason error) {
+			//empty
+		}
+	}
+
+	if c.CheckOrigin == nil {
+		c.CheckOrigin = func(r *http.Request) bool {
+			// allow all connections by default
+			return true
+		}
+	}
+
+	if c.IDGenerator == nil {
+		c.IDGenerator = DefaultIDGenerator
+	}
+
+	return c
+}