From 2042fddb66c73691074540fab9375320f83d88c0 Mon Sep 17 00:00:00 2001
From: "Gerasimos (Makis) Maropoulos" <kataras2006@hotmail.com>
Date: Wed, 20 Dec 2017 17:56:28 +0200
Subject: [PATCH] Another new feature: websocket controller, for real

Former-commit-id: c1a59b86733e890709b52446e22427a17d87f5fc
---
 _examples/README.md                      |  6 +-
 _examples/mvc/singleton/main.go          | 33 ++++++++
 _examples/mvc/websocket/main.go          | 82 ++++++++++++++++++++
 _examples/mvc/websocket/views/index.html | 63 +++++++++++++++
 _examples/websocket/chat/main.go         |  3 +-
 websocket/client.go                      |  5 +-
 websocket/client.ts                      |  5 +-
 websocket/connection.go                  | 40 +++++++++-
 websocket/emitter.go                     |  6 +-
 websocket/server.go                      | 99 +++++++++++++-----------
 10 files changed, 281 insertions(+), 61 deletions(-)
 create mode 100644 _examples/mvc/singleton/main.go
 create mode 100644 _examples/mvc/websocket/main.go
 create mode 100644 _examples/mvc/websocket/views/index.html

diff --git a/_examples/README.md b/_examples/README.md
index 44bb0f2c..14f01666 100644
--- a/_examples/README.md
+++ b/_examples/README.md
@@ -212,8 +212,10 @@ Follow the examples below,
 
 - [Hello world](mvc/hello-world/main.go) **UPDATED**
 - [Session Controller](mvc/session-controller/main.go) **UPDATED**
-- [Overview - Plus Repository and Service layers](mvc/overview) **NEW**
-- [Login showcase - Plus Repository and Service layers](mvc/login) **NEW**
+- [Overview - Plus Repository and Service layers](mvc/overview) **UPDATED**
+- [Login showcase - Plus Repository and Service layers](mvc/login) **UPDATED**
+- [Singleton](mvc/singleton) **NEW**
+- [Websocket Controller](mvc/websocket) **NEW**
 
 <!-- 
 Why updated?
diff --git a/_examples/mvc/singleton/main.go b/_examples/mvc/singleton/main.go
new file mode 100644
index 00000000..6c31cb49
--- /dev/null
+++ b/_examples/mvc/singleton/main.go
@@ -0,0 +1,33 @@
+package main
+
+import (
+	"fmt"
+	"sync/atomic"
+
+	"github.com/kataras/iris"
+	"github.com/kataras/iris/mvc"
+)
+
+func main() {
+	app := iris.New()
+	mvc.New(app.Party("/")).Register(new(globalVisitorsController))
+
+	// http://localhost:8080
+	app.Run(iris.Addr(":8080"))
+}
+
+type globalVisitorsController struct {
+	// When a singleton controller is used then concurent safe access is up to the developers, because
+	// all clients share the same controller instance instead. Note that any controller's methods
+	// are per-client, but the struct's field can be shared accross multiple clients if the structure
+	// does not have any dynamic struct field depenendies that depend on the iris.Context,
+	// this declares a Singleton, note that you don't have to write a single line of code to do this, Iris is smart enough.
+	//
+	// see `Get`.
+	visits uint64
+}
+
+func (c *globalVisitorsController) Get() string {
+	count := atomic.AddUint64(&c.visits, 1)
+	return fmt.Sprintf("Total visitors: %d", count)
+}
diff --git a/_examples/mvc/websocket/main.go b/_examples/mvc/websocket/main.go
new file mode 100644
index 00000000..3f6483c8
--- /dev/null
+++ b/_examples/mvc/websocket/main.go
@@ -0,0 +1,82 @@
+package main
+
+import (
+	"sync/atomic"
+
+	"github.com/kataras/iris"
+	"github.com/kataras/iris/mvc"
+	"github.com/kataras/iris/websocket"
+)
+
+func main() {
+	app := iris.New()
+	// load templaes.
+	app.RegisterView(iris.HTML("./views", ".html"))
+
+	// render the ./views/index.html.
+	app.Get("/", func(ctx iris.Context) {
+		ctx.View("index.html")
+	})
+
+	mvc.Configure(app.Party("/websocket"), configureMVC)
+	// Or mvc.New(app.Party(...)).Configure(configureMVC)
+
+	// http://localhost:8080
+	app.Run(iris.Addr(":8080"))
+}
+
+func configureMVC(m *mvc.Application) {
+	ws := websocket.New(websocket.Config{})
+	// http://localhost:8080/websocket/iris-ws.js
+	m.Router.Any("/iris-ws.js", websocket.ClientHandler())
+
+	// This will bind the result of ws.Upgrade which is a websocket.Connection
+	// to the controller(s) registered via `m.Register`.
+	m.AddDependencies(ws.Upgrade)
+	m.Register(new(websocketController))
+}
+
+var visits uint64
+
+func increment() uint64 {
+	return atomic.AddUint64(&visits, 1)
+}
+
+func decrement() uint64 {
+	return atomic.AddUint64(&visits, ^uint64(0))
+}
+
+type websocketController struct {
+	// Note that you could use an anonymous field as well, it doesn't matter, binder will find it.
+	//
+	// This is the current websocket connection, each client has its own instance of the *websocketController.
+	Conn websocket.Connection
+}
+
+func (c *websocketController) onLeave(roomName string) {
+	// visits--
+	newCount := decrement()
+	// This will call the "visit" event on all clients, except the current one,
+	// (it can't because it's left but for any case use this type of design)
+	c.Conn.To(websocket.Broadcast).Emit("visit", newCount)
+}
+
+func (c *websocketController) update() {
+	// visits++
+	newCount := increment()
+
+	// This will call the "visit" event on all clients, incuding the current
+	// with the 'newCount' variable.
+	//
+	// There are many ways that u can do it and faster, for example u can just send a new visitor
+	// and client can increment itself, but here we are just "showcasing" the websocket controller.
+	c.Conn.To(websocket.All).Emit("visit", newCount)
+}
+
+func (c *websocketController) Get( /* websocket.Connection could be lived here as well, it doesn't matter */ ) {
+	c.Conn.OnLeave(c.onLeave)
+	c.Conn.On("visit", c.update)
+
+	// call it after all event callbacks registration.
+	c.Conn.Wait()
+}
diff --git a/_examples/mvc/websocket/views/index.html b/_examples/mvc/websocket/views/index.html
new file mode 100644
index 00000000..ecedcff2
--- /dev/null
+++ b/_examples/mvc/websocket/views/index.html
@@ -0,0 +1,63 @@
+<html>
+
+<head>
+    <title>Online visitors MVC example</title>
+    <style>
+        body {
+            margin: 0;
+            font-family: -apple-system, "San Francisco", "Helvetica Neue", "Noto", "Roboto", "Calibri Light", sans-serif;
+            color: #212121;
+            font-size: 1.0em;
+            line-height: 1.6;
+        }
+
+        .container {
+            max-width: 750px;
+            margin: auto;
+            padding: 15px;
+        }
+
+        #online_visitors {
+            font-weight: bold;
+            font-size: 18px;
+        }
+    </style>
+</head>
+
+<body>
+    <div class="container">
+        <span id="online_visitors">1 online visitor</span>
+    </div>
+
+    <script src="/websocket/iris-ws.js"></script>
+
+    <script type="text/javascript">
+        (function () {
+            var socket = new Ws("ws://localhost:8080/websocket");
+
+            socket.OnConnect(function(){
+                // update the rest of connected clients, including "myself" when "my" connection is 100% ready.
+                socket.Emit("visit");
+            });
+        
+
+            socket.On("visit", function (newCount) {
+                console.log("visit websocket event with newCount of: ", newCount);
+
+                var text = "1 online visitor";
+                if (newCount > 1) {
+                    text = newCount + " online visitors";
+                }
+                document.getElementById("online_visitors").innerHTML = text;
+            });
+
+            socket.OnDisconnect(function () {
+                document.getElementById("online_visitors").innerHTML = "you've been disconnected";
+            });
+
+        })();
+    </script>
+
+</body>
+
+</html>
\ No newline at end of file
diff --git a/_examples/websocket/chat/main.go b/_examples/websocket/chat/main.go
index d3b33a0d..d1adeacb 100644
--- a/_examples/websocket/chat/main.go
+++ b/_examples/websocket/chat/main.go
@@ -47,8 +47,9 @@ func handleConnection(c websocket.Connection) {
 	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:
+		// Write message back to the client message owner with:
 		// c.Emit("chat", msg)
+		// Write message to all except this client with:
 		c.To(websocket.Broadcast).Emit("chat", msg)
 	})
 }
diff --git a/websocket/client.go b/websocket/client.go
index 77d06962..771e5eb8 100644
--- a/websocket/client.go
+++ b/websocket/client.go
@@ -105,8 +105,9 @@ var Ws = (function () {
             t = websocketJSONMessageType;
             m = JSON.stringify(data);
         }
-        else {
-            console.log("Invalid, javascript-side should contains an empty second parameter.");
+        else if (data !== null && typeof(data) !== "undefined" ) {
+            // if it has a second parameter but it's not a type we know, then fire this:
+            console.log("unsupported type of input argument passed, try to not include this argument to the 'Emit'");
         }
         return this._msg(event, t, m);
     };
diff --git a/websocket/client.ts b/websocket/client.ts
index b4b38413..98392492 100644
--- a/websocket/client.ts
+++ b/websocket/client.ts
@@ -106,8 +106,9 @@ class Ws {
             //propably json-object
             t = websocketJSONMessageType;
             m = JSON.stringify(data);
-        } else {
-            console.log("Invalid, javascript-side should contains an empty second parameter.");
+        } else if (data !== null && typeof (data) !== "undefined") {
+            // if it has a second parameter but it's not a type we know, then fire this:
+            console.log("unsupported type of input argument passed, try to not include this argument to the 'Emit'");
         }
 
         return this._msg(event, t, m);
diff --git a/websocket/connection.go b/websocket/connection.go
index 9f18dcbd..2d6a93da 100644
--- a/websocket/connection.go
+++ b/websocket/connection.go
@@ -137,6 +137,9 @@ type (
 	Connection interface {
 		// Emitter implements EmitMessage & Emit
 		Emitter
+		// Err is not nil if the upgrader failed to upgrade http to websocket connection.
+		Err() error
+
 		// ID returns the connection's identifier
 		ID() string
 
@@ -181,6 +184,11 @@ type (
 		// Note: the callback(s) called right before the server deletes the connection from the room
 		// so the connection theoretical can still send messages to its room right before it is being disconnected.
 		OnLeave(roomLeaveCb LeaveRoomFunc)
+		// Wait starts the pinger and the messages reader,
+		// it's named as "Wait" because it should be called LAST,
+		// after the "On" events IF server's `Upgrade` is used,
+		// otherise you don't have to call it because the `Handler()` does it automatically.
+		Wait()
 		// Disconnect disconnects the client, close the underline websocket conn and removes it from the conn list
 		// returns the error, if any, from the underline connection
 		Disconnect() error
@@ -197,6 +205,7 @@ type (
 	}
 
 	connection struct {
+		err                      error
 		underline                UnderlineConnection
 		id                       string
 		messageType              int
@@ -207,6 +216,7 @@ type (
 		onPingListeners          []PingFunc
 		onNativeMessageListeners []NativeMessageFunc
 		onEventListeners         map[string][]MessageFunc
+		started                  bool
 		// these were  maden for performance only
 		self      Emitter // pre-defined emitter than sends message to its self client
 		broadcast Emitter // pre-defined emitter that sends message to all except this
@@ -237,6 +247,7 @@ func newConnection(ctx context.Context, s *Server, underlineConn UnderlineConnec
 		onErrorListeners:         make([]ErrorFunc, 0),
 		onNativeMessageListeners: make([]NativeMessageFunc, 0),
 		onEventListeners:         make(map[string][]MessageFunc, 0),
+		started:                  false,
 		ctx:                      ctx,
 		server:                   s,
 	}
@@ -252,6 +263,11 @@ func newConnection(ctx context.Context, s *Server, underlineConn UnderlineConnec
 	return c
 }
 
+// Err is not nil if the upgrader failed to upgrade http to websocket connection.
+func (c *connection) Err() error {
+	return c.err
+}
+
 // write writes a raw websocket message with a specific type to the client
 // used by ping messages and any CloseMessage types.
 func (c *connection) write(websocketMessageType int, data []byte) error {
@@ -322,6 +338,13 @@ func (c *connection) startPinger() {
 	}()
 }
 
+func (c *connection) fireOnPing() {
+	// fire the onPingListeners
+	for i := range c.onPingListeners {
+		c.onPingListeners[i]()
+	}
+}
+
 func (c *connection) startReader() {
 	conn := c.underline
 	hasReadTimeout := c.server.config.ReadTimeout > 0
@@ -503,11 +526,20 @@ func (c *connection) fireOnLeave(roomName string) {
 	}
 }
 
-func (c *connection) fireOnPing() {
-	// fire the onPingListeners
-	for i := range c.onPingListeners {
-		c.onPingListeners[i]()
+// Wait starts the pinger and the messages reader,
+// it's named as "Wait" because it should be called LAST,
+// after the "On" events IF server's `Upgrade` is used,
+// otherise you don't have to call it because the `Handler()` does it automatically.
+func (c *connection) Wait() {
+	if c.started {
+		return
 	}
+	c.started = true
+	// start the ping
+	c.startPinger()
+
+	// start the messages reader
+	c.startReader()
 }
 
 func (c *connection) Disconnect() error {
diff --git a/websocket/emitter.go b/websocket/emitter.go
index 5827b24d..859bf0ee 100644
--- a/websocket/emitter.go
+++ b/websocket/emitter.go
@@ -1,10 +1,10 @@
 package websocket
 
 const (
-	// All is the string which the Emitter use to send a message to all
+	// All is the string which the Emitter use to send a message to all.
 	All = ""
-	// Broadcast is the string which the Emitter use to send a message to all except this connection
-	Broadcast = ";ionwebsocket;to;all;except;me;"
+	// Broadcast is the string which the Emitter use to send a message to all except this connection.
+	Broadcast = ";to;all;except;me;"
 )
 
 type (
diff --git a/websocket/server.go b/websocket/server.go
index 3ef38450..cd17c3ce 100644
--- a/websocket/server.go
+++ b/websocket/server.go
@@ -109,7 +109,7 @@ type (
 		mu                    sync.RWMutex        // for rooms
 		onConnectionListeners []ConnectionFunc
 		//connectionPool        sync.Pool // sadly we can't make this because the websocket connection is live until is closed.
-		handler context.Handler
+		upgrader websocket.Upgrader
 	}
 )
 
@@ -119,10 +119,20 @@ type (
 //
 // To serve the built'n javascript client-side library look the `websocket.ClientHandler`.
 func New(cfg Config) *Server {
+	cfg = cfg.Validate()
 	return &Server{
-		config: cfg.Validate(),
+		config: cfg,
 		rooms:  make(map[string][]string, 0),
 		onConnectionListeners: make([]ConnectionFunc, 0),
+		upgrader: websocket.Upgrader{
+			HandshakeTimeout:  cfg.HandshakeTimeout,
+			ReadBufferSize:    cfg.ReadBufferSize,
+			WriteBufferSize:   cfg.WriteBufferSize,
+			Error:             cfg.Error,
+			CheckOrigin:       cfg.CheckOrigin,
+			Subprotocols:      cfg.Subprotocols,
+			EnableCompression: cfg.EnableCompression,
+		},
 	}
 }
 
@@ -135,40 +145,50 @@ func New(cfg Config) *Server {
 //
 // To serve the built'n javascript client-side library look the `websocket.ClientHandler`.
 func (s *Server) Handler() context.Handler {
-	// build the upgrader once
-	c := s.config
-
-	upgrader := websocket.Upgrader{
-		HandshakeTimeout:  c.HandshakeTimeout,
-		ReadBufferSize:    c.ReadBufferSize,
-		WriteBufferSize:   c.WriteBufferSize,
-		Error:             c.Error,
-		CheckOrigin:       c.CheckOrigin,
-		Subprotocols:      c.Subprotocols,
-		EnableCompression: c.EnableCompression,
-	}
-
 	return func(ctx context.Context) {
-		// Upgrade upgrades the HTTP Server connection to the WebSocket protocol.
-		//
-		// The responseHeader is included in the response to the client's upgrade
-		// request. Use the responseHeader to specify cookies (Set-Cookie) and the
-		// application negotiated subprotocol (Sec--Protocol).
-		//
-		// If the upgrade fails, then Upgrade replies to the client with an HTTP error
-		// response.
-		conn, err := upgrader.Upgrade(ctx.ResponseWriter(), ctx.Request(), ctx.ResponseWriter().Header())
-		if err != nil {
-			ctx.Application().Logger().Warnf("websocket error: %v\n", err)
-			ctx.StatusCode(503) // Status Service Unavailable
-			return
+		c := s.Upgrade(ctx)
+		// NOTE TO ME: fire these first BEFORE startReader and startPinger
+		// in order to set the events and any messages to send
+		// the startPinger will send the OK to the client and only
+		// then the client is able to send and receive from Server
+		// when all things are ready and only then. DO NOT change this order.
+
+		// fire the on connection event callbacks, if any
+		for i := range s.onConnectionListeners {
+			s.onConnectionListeners[i](c)
 		}
-		s.handleConnection(ctx, conn)
+
+		// start the ping and the messages reader
+		c.Wait()
 	}
 }
 
-// handleConnection creates & starts to listening to a new connection
-func (s *Server) handleConnection(ctx context.Context, websocketConn UnderlineConnection) {
+// Upgrade upgrades the HTTP Server connection to the WebSocket protocol.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// application negotiated subprotocol (Sec--Protocol).
+//
+// If the upgrade fails, then Upgrade replies to the client with an HTTP error
+// response and the return `Connection.Err()` is filled with that error.
+//
+// For a more high-level function use the `Handler()` and `OnConnecton` events.
+// This one does not starts the connection's writer and reader, so after your `On/OnMessage` events registration
+// the caller has to call the `Connection#Wait` function, otherwise the connection will be not handled.
+func (s *Server) Upgrade(ctx context.Context) Connection {
+	conn, err := s.upgrader.Upgrade(ctx.ResponseWriter(), ctx.Request(), ctx.ResponseWriter().Header())
+	if err != nil {
+		ctx.Application().Logger().Warnf("websocket error: %v\n", err)
+		ctx.StatusCode(503) // Status Service Unavailable
+		return &connection{err: err}
+	}
+
+	return s.handleConnection(ctx, conn)
+}
+
+// wrapConnection wraps an underline connection to an iris websocket connection.
+// It does NOT starts its writer, reader and event mux, the caller is responsible for that.
+func (s *Server) handleConnection(ctx context.Context, websocketConn UnderlineConnection) *connection {
 	// use the config's id generator (or the default) to create a websocket client/connection id
 	cid := s.config.IDGenerator(ctx)
 	// create the new connection
@@ -179,22 +199,7 @@ func (s *Server) handleConnection(ctx context.Context, websocketConn UnderlineCo
 	// join to itself
 	s.Join(c.ID(), c.ID())
 
-	// NOTE TO ME: fire these first BEFORE startReader and startPinger
-	// in order to set the events and any messages to send
-	// the startPinger will send the OK to the client and only
-	// then the client is able to send and receive from Server
-	// when all things are ready and only then. DO NOT change this order.
-
-	// fire the on connection event callbacks, if any
-	for i := range s.onConnectionListeners {
-		s.onConnectionListeners[i](c)
-	}
-
-	// start the ping
-	c.startPinger()
-
-	// start the messages reader
-	c.startReader()
+	return c
 }
 
 /* Notes: