lots of api changes

use jsonapi to format responses
add somewhat working websockets

api/websockets/client.go

@@ -0,0 +1,76 @@
+package websockets
+
+import "github.com/gorilla/websocket"
+import (
+	"time"
+
+	log "github.com/sirupsen/logrus"
+)
+
+type Client struct {
+	hub *Hub
+
+	socket *websocket.Conn
+
+	send chan []byte
+}
+
+func (c *Client) readPump() {
+	defer func() {
+		c.hub.unregister <- c
+		c.socket.Close()
+	}()
+	c.socket.SetReadLimit(maxMessageSize)
+	c.socket.SetReadDeadline(time.Now().Add(pongWait))
+	c.socket.SetPongHandler(func(string) error {
+		c.socket.SetReadDeadline(time.Now().Add(pongWait))
+		return nil
+	})
+	for {
+		_, _, err := c.socket.ReadMessage()
+		if err != nil {
+			if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway) {
+				log.WithError(err).Debug("Websocket closed unexpectedly.")
+			}
+			return
+		}
+	}
+}
+
+func (c *Client) writePump() {
+	ticker := time.NewTicker(pingPeriod)
+	defer func() {
+		ticker.Stop()
+		c.socket.Close()
+	}()
+	for {
+		select {
+		case m, ok := <-c.send:
+			c.socket.SetWriteDeadline(time.Now().Add(writeWait))
+			if !ok {
+				// The hub closed the channel
+				c.socket.WriteMessage(websocket.CloseMessage, []byte{})
+				return
+			}
+			w, err := c.socket.NextWriter(websocket.TextMessage)
+			if err != nil {
+				return
+			}
+			w.Write([]byte{'['})
+			w.Write(m)
+			for i := 0; i < len(c.send)+1; i++ {
+				w.Write([]byte{','})
+				w.Write(<-c.send)
+			}
+			w.Write([]byte{']'})
+			if err := w.Close(); err != nil {
+				return
+			}
+		case <-ticker.C:
+			c.socket.SetWriteDeadline(time.Now().Add(writeWait))
+			if err := c.socket.WriteMessage(websocket.PingMessage, []byte{}); err != nil {
+				return
+			}
+		}
+	}
+}

api/websockets/consolewriter.go

@@ -0,0 +1,28 @@
+package websockets
+
+import "io"
+
+type ConsoleWriter struct {
+	Hub         *Hub
+	HandlerFunc *func(string)
+}
+
+var _ io.Writer = ConsoleWriter{}
+
+func (c ConsoleWriter) Write(b []byte) (n int, e error) {
+	line := make([]byte, len(b))
+	copy(line, b)
+	m := Message{
+		Type: MessageTypeConsole,
+		Payload: ConsolePayload{
+			Line:   string(line),
+			Level:  ConsoleLevelPlain,
+			Source: ConsoleSourceServer,
+		},
+	}
+	c.Hub.Broadcast <- m
+	if c.HandlerFunc != nil {
+		(*c.HandlerFunc)(string(line))
+	}
+	return len(b), nil
+}

api/websockets/hub.go

@@ -0,0 +1,120 @@
+package websockets
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"github.com/gorilla/websocket"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	writeWait = 10 * time.Second
+	pongWait  = 60 * time.Second
+
+	pingPeriod = pongWait * 9 / 10
+
+	maxMessageSize = 512
+)
+
+var wsupgrader = websocket.Upgrader{
+	ReadBufferSize:  1024,
+	WriteBufferSize: 1024,
+	CheckOrigin: func(r *http.Request) bool {
+		return true
+	},
+}
+
+type websocketMap map[*Client]bool
+
+type Hub struct {
+	clients websocketMap
+
+	Broadcast chan Message
+
+	register   chan *Client
+	unregister chan *Client
+	close      chan bool
+}
+
+//var _ io.Writer = &Hub{}
+
+func NewHub() *Hub {
+	return &Hub{
+		Broadcast:  make(chan Message),
+		register:   make(chan *Client),
+		unregister: make(chan *Client),
+		close:      make(chan bool),
+		clients:    make(websocketMap),
+	}
+}
+
+func (h *Hub) Upgrade(w http.ResponseWriter, r *http.Request) {
+	socket, err := wsupgrader.Upgrade(w, r, nil)
+	if err != nil {
+		log.WithError(err).Error("Failed to upgrade to websocket")
+		return
+	}
+	c := &Client{
+		hub:    h,
+		socket: socket,
+		send:   make(chan []byte, 256),
+	}
+	h.register <- c
+
+	go c.readPump()
+	go c.writePump()
+}
+
+func (h *Hub) Subscribe(c *Client) {
+	h.register <- c
+}
+
+func (h *Hub) Unsubscribe(c *Client) {
+	h.unregister <- c
+}
+
+func (h *Hub) Run() {
+	defer func() {
+		for s := range h.clients {
+			close(s.send)
+			delete(h.clients, s)
+		}
+		close(h.register)
+		close(h.unregister)
+		close(h.Broadcast)
+		close(h.close)
+	}()
+	for {
+		select {
+		case s := <-h.register:
+			h.clients[s] = true
+		case s := <-h.unregister:
+			if _, ok := h.clients[s]; ok {
+				delete(h.clients, s)
+				close(s.send)
+			}
+		case m := <-h.Broadcast:
+			b, err := json.Marshal(m)
+			if err != nil {
+				log.WithError(err).Error("Failed to encode websocket message.")
+				continue
+			}
+			for s := range h.clients {
+				select {
+				case s.send <- b:
+				default:
+					close(s.send)
+					delete(h.clients, s)
+				}
+			}
+		case <-h.close:
+			return
+		}
+	}
+}
+
+func (h *Hub) Close() {
+	h.close <- true
+}

api/websockets/message.go

@@ -0,0 +1,59 @@
+package websockets
+
+type MessageType string
+
+const (
+	MessageTypeProc    MessageType = "proc"
+	MessageTypeConsole MessageType = "console"
+	MessageTypeStatus  MessageType = "status"
+)
+
+// Message is a message that can be sent using a websocket in JSON format
+type Message struct {
+	// Type is the type of a websocket message
+	Type MessageType `json:"type"`
+	// Payload is the payload of the message
+	// The payload needs to support encoding in JSON
+	Payload interface{} `json:"payload"`
+}
+
+type ProcPayload struct {
+	Memory   int   `json:"memory"`
+	CPUCores []int `json:"cpu_cores"`
+	CPUTotal int   `json:"cpu_total"`
+	Disk     int   `json:"disk"`
+}
+
+type ConsoleSource string
+type ConsoleLevel string
+
+const (
+	ConsoleSourceWings  ConsoleSource = "wings"
+	ConsoleSourceServer ConsoleSource = "server"
+
+	ConsoleLevelPlain ConsoleLevel = "plain"
+	ConsoleLevelInfo  ConsoleLevel = "info"
+	ConsoleLevelWarn  ConsoleLevel = "warn"
+	ConsoleLevelError ConsoleLevel = "error"
+)
+
+type ConsolePayload struct {
+	// Source is the source of the console line, either ConsoleSourceWings or ConsoleSourceServer
+	Source ConsoleSource `json:"source"`
+	// Level is the level of the message.
+	// Use one of plain, info, warn or error. If omitted the default is plain.
+	Level ConsoleLevel `json:"level,omitempty"`
+	// Line is the actual line to print to the console.
+	Line string `json:"line"`
+}
+
+func (h *Hub) Log(l ConsoleLevel, m string) {
+	h.Broadcast <- Message{
+		Type: MessageTypeConsole,
+		Payload: ConsolePayload{
+			Source: ConsoleSourceWings,
+			Level:  l,
+			Line:   m,
+		},
+	}
+}