100 lines
1.8 KiB
Go
100 lines
1.8 KiB
Go
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package websockets
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import (
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"encoding/json"
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"sync"
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"sync/atomic"
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"time"
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"github.com/leavengood/websocket"
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)
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var stepNumber uint64
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func handler(rawConn *websocket.Conn) {
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defer rawConn.Close()
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step := atomic.AddUint64(&stepNumber, 1)
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// 5 is a security margin in case
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if step == (1<<10 - 5) {
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atomic.StoreUint64(&stepNumber, 0)
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}
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c := &conn{
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rawConn,
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sync.Mutex{},
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step | uint64(time.Now().UnixNano()<<10),
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}
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c.WriteJSON(TypeConnected, nil)
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defer cleanup(c.ID)
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for {
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var i incomingMessage
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err := c.Conn.ReadJSON(&i)
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if _, ok := err.(*websocket.CloseError); ok {
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return
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}
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if err != nil {
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c.WriteJSON(TypeInvalidMessage, err.Error())
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continue
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}
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f, ok := messageHandler[i.Type]
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if !ok {
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c.WriteJSON(TypeInvalidMessage, "invalid message type")
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continue
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}
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f(c, i)
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}
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}
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type conn struct {
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Conn *websocket.Conn
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Mtx sync.Mutex
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ID uint64
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}
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func (c *conn) WriteJSON(t string, data interface{}) error {
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c.Mtx.Lock()
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err := c.Conn.WriteJSON(newMessage(t, data))
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c.Mtx.Unlock()
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return err
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}
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var messageHandler = map[string]func(c *conn, message incomingMessage){
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TypeSubscribeScores: SubscribeScores,
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}
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// Server Message Types
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const (
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TypeConnected = "connected"
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TypeInvalidMessage = "invalid_message_type"
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TypeSubscribed = "subscribed"
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TypeNewScore = "new_score"
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)
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// Client Message Types
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const (
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TypeSubscribeScores = "subscribe_scores"
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)
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// Message is the wrapped information for a message sent to the client.
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type Message struct {
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Type string `json:"type"`
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Data interface{} `json:"data,omitempty"`
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}
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func newMessage(t string, data interface{}) Message {
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return Message{
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Type: t,
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Data: data,
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}
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}
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type incomingMessage struct {
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Type string `json:"type"`
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Data json.RawMessage `json:"data"`
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}
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