Release v1.0.2-pre8

* [316-multi-bridge-conn] feat: use callback func for bridge response

* [316-multi-bridge-conn] feat: implement multiple session support

* split client handling portion into 'session'
* keep track of sessions by remote address (ip & port)
* notify each of the sessions anytime an event comes across the bus

* [316-multi-bridge-conn] chore: move bridge files to package

* [316-multi-bridge-conn] chore: remove deprecated Callback function

The Callback function is no longer needed for the operation of
the frontend callback since the ipc.Dispatch function now requires
a callback function to be provided as an argument.
This function can be a private function since it is passed by reference.

* [316-multi-bridge-conn] chore: make webview.Callback private

* [316-multi-bridge-conn] chore: remove unused injectCSS function

I believe a slightly better method of doing this might need to be devised
if it is needed in the future. I presume it should collect the values
into a cache and then inject it into each sesssion as it appears.

* [316-multi-bridge-conn] ensure wails:ready event is emitted

Event is only emitted for the first session created from the Bridge.

* [316-multi-bridge-conn] emit events for session lifecycle

Emit an event for each session started and ended.

* [316-multi-bridge-conn] fix: session handling fixes

Co-authored-by: Lea Anthony <lea.anthony@gmail.com>

app.go

@@ -97,7 +97,7 @@ func (a *App) start() error {
 
 	// Check if we are to run in bridge mode
 	if BuildMode == cmd.BuildModeBridge {
-		a.renderer = &renderer.Bridge{}
+		a.renderer = renderer.NewBridge()
 	}
 
 	// Initialise the renderer

cmd/version.go

@@ -1,4 +1,4 @@
 package cmd
 
 // Version - Wails version
-const Version = "v1.0.2-pre6"
+const Version = "v1.0.2-pre8"

lib/binding/manager.go

@@ -114,6 +114,7 @@ func (b *Manager) generateTypescriptDefinitions() error {
 	var output strings.Builder
 
 	for structname, methodList := range b.structList {
+		structname = strings.SplitN(structname, ".", 2)[1]
 		output.WriteString(fmt.Sprintf("Interface %s {\n", structname))
 		for _, method := range methodList {
 			output.WriteString(fmt.Sprintf("\t%s: (...args : any[]) => Promise\n", method))
@@ -125,6 +126,7 @@ func (b *Manager) generateTypescriptDefinitions() error {
 	output.WriteString("Interface Backend {\n")
 
 	for structname := range b.structList {
+		structname = strings.SplitN(structname, ".", 2)[1]
 		output.WriteString(fmt.Sprintf("\t%[1]s: %[1]s\n", structname))
 	}
 	output.WriteString("}\n")

lib/interfaces/ipcmanager.go

@@ -1,9 +1,13 @@
 package interfaces
 
+// CallbackFunc defines the signature of a function required to be provided to the
+// Dispatch function so that the response may be returned
+type CallbackFunc func(string) error
+
 // IPCManager is the event manager interface
 type IPCManager interface {
 	BindRenderer(Renderer)
-	Dispatch(message string)
+	Dispatch(message string, f CallbackFunc)
 	Start(eventManager EventManager, bindingManager BindingManager)
 	Shutdown()
 }

lib/interfaces/renderer.go

@@ -12,7 +12,6 @@ type Renderer interface {
 
 	// Binding
 	NewBinding(bindingName string) error
-	Callback(data string) error
 
 	// Events
 	NotifyEvent(eventData *messages.EventData) error

lib/ipc/manager.go

@@ -135,10 +135,10 @@ func (i *Manager) Start(eventManager interfaces.EventManager, bindingManager int
 // Dispatch receives JSON encoded messages from the renderer.
 // It processes the message to ensure that it is valid and places
 // the processed message on the message queue
-func (i *Manager) Dispatch(message string) {
+func (i *Manager) Dispatch(message string, cb interfaces.CallbackFunc) {
 
 	// Create a new IPC Message
-	incomingMessage, err := newIPCMessage(message, i.SendResponse)
+	incomingMessage, err := newIPCMessage(message, i.SendResponse(cb))
 	if err != nil {
 		i.log.ErrorFields("Could not understand incoming message! ", map[string]interface{}{
 			"message": message,
@@ -158,17 +158,19 @@ func (i *Manager) Dispatch(message string) {
 }
 
 // SendResponse sends the given response back to the frontend
-func (i *Manager) SendResponse(response *ipcResponse) error {
+// It sends the data back to the correct renderer by way of the provided callback function
+func (i *Manager) SendResponse(cb interfaces.CallbackFunc) func(i *ipcResponse) error {
 
-	// Serialise the Message
+	return func(response *ipcResponse) error {
-	data, err := response.Serialise()
+		// Serialise the Message
-	if err != nil {
+		data, err := response.Serialise()
-		fmt.Printf(err.Error())
+		if err != nil {
-		return err
+			fmt.Printf(err.Error())
+			return err
+		}
+		return cb(data)
 	}
 
-	// Call back to the front end
-	return i.renderer.Callback(data)
 }
 
 // Shutdown is called when exiting the Application

lib/renderer/bridge.go

@@ -1,262 +1,10 @@
 package renderer
 
 import (
-	"encoding/json"
+	bridge "github.com/wailsapp/wails/lib/renderer/bridge"
-	"fmt"
-	"net/http"
-	"strings"
-	"sync"
-
-	"github.com/dchest/htmlmin"
-	"github.com/gorilla/websocket"
-	"github.com/leaanthony/mewn"
-	"github.com/wailsapp/wails/lib/interfaces"
-	"github.com/wailsapp/wails/lib/logger"
-	"github.com/wailsapp/wails/lib/messages"
 )
 
-type messageType int
+// NewBridge returns a new Bridge struct
-
+func NewBridge() *bridge.Bridge {
-const (
+	return &bridge.Bridge{}
-	jsMessage messageType = iota
-	cssMessage
-	htmlMessage
-	notifyMessage
-	bindingMessage
-	callbackMessage
-	wailsRuntimeMessage
-)
-
-func (m messageType) toString() string {
-	return [...]string{"j", "s", "h", "n", "b", "c", "w"}[m]
-}
-
-// Bridge is a backend that opens a local web server
-// and renders the files over a websocket
-type Bridge struct {
-	// Common
-	log          *logger.CustomLogger
-	ipcManager   interfaces.IPCManager
-	appConfig    interfaces.AppConfig
-	eventManager interfaces.EventManager
-	bindingCache []string
-
-	// Bridge specific
-	initialisationJS []string
-	server           *http.Server
-	theConnection    *websocket.Conn
-
-	// Mutex for writing to the socket
-	lock sync.Mutex
-}
-
-// Initialise the Bridge Renderer
-func (h *Bridge) Initialise(appConfig interfaces.AppConfig, ipcManager interfaces.IPCManager, eventManager interfaces.EventManager) error {
-	h.ipcManager = ipcManager
-	h.appConfig = appConfig
-	h.eventManager = eventManager
-	ipcManager.BindRenderer(h)
-	h.log = logger.NewCustomLogger("Bridge")
-	return nil
-}
-
-func (h *Bridge) evalJS(js string, mtype messageType) error {
-
-	message := mtype.toString() + js
-
-	if h.theConnection == nil {
-		h.initialisationJS = append(h.initialisationJS, message)
-	} else {
-		// Prepend message type to message
-		h.sendMessage(h.theConnection, message)
-	}
-
-	return nil
-}
-
-// EnableConsole not needed for bridge!
-func (h *Bridge) EnableConsole() {
-}
-
-func (h *Bridge) injectCSS(css string) {
-	// Minify css to overcome issues in the browser with carriage returns
-	minified, err := htmlmin.Minify([]byte(css), &htmlmin.Options{
-		MinifyStyles: true,
-	})
-	if err != nil {
-		h.log.Fatal("Unable to minify CSS: " + css)
-	}
-	minifiedCSS := string(minified)
-	minifiedCSS = strings.Replace(minifiedCSS, "\\", "\\\\", -1)
-	minifiedCSS = strings.Replace(minifiedCSS, "'", "\\'", -1)
-	minifiedCSS = strings.Replace(minifiedCSS, "\n", " ", -1)
-	inject := fmt.Sprintf("wails._.InjectCSS('%s')", minifiedCSS)
-	h.evalJS(inject, cssMessage)
-}
-
-func (h *Bridge) wsBridgeHandler(w http.ResponseWriter, r *http.Request) {
-	conn, err := websocket.Upgrade(w, r, w.Header(), 1024, 1024)
-	if err != nil {
-		http.Error(w, "Could not open websocket connection", http.StatusBadRequest)
-	}
-	h.theConnection = conn
-	h.log.Infof("Connection from frontend accepted [%p].", h.theConnection)
-	conn.SetCloseHandler(func(int, string) error {
-		h.log.Infof("Connection dropped [%p].", h.theConnection)
-		h.theConnection = nil
-		return nil
-	})
-	go h.start(conn)
-}
-
-func (h *Bridge) sendMessage(conn *websocket.Conn, msg string) {
-
-	h.lock.Lock()
-	defer h.lock.Unlock()
-
-	if err := conn.WriteMessage(websocket.TextMessage, []byte(msg)); err != nil {
-		h.log.Error(err.Error())
-	}
-}
-
-func (h *Bridge) start(conn *websocket.Conn) {
-
-	// set external.invoke
-	h.log.Infof("Connected to frontend.")
-
-	wailsRuntime := mewn.String("../../runtime/assets/wails.js")
-	h.evalJS(wailsRuntime, wailsRuntimeMessage)
-
-	// Inject bindings
-	for _, binding := range h.bindingCache {
-		h.evalJS(binding, bindingMessage)
-	}
-
-	// Emit that everything is loaded and ready
-	h.eventManager.Emit("wails:ready")
-
-	for {
-		messageType, buffer, err := conn.ReadMessage()
-		if messageType == -1 {
-			return
-		}
-		if err != nil {
-			h.log.Errorf("Error reading message: ", err)
-			continue
-		}
-
-		h.log.Debugf("Got message: %#v\n", string(buffer))
-
-		h.ipcManager.Dispatch(string(buffer))
-	}
-}
-
-// Run the app in Bridge mode!
-func (h *Bridge) Run() error {
-	h.server = &http.Server{Addr: ":34115"}
-	http.HandleFunc("/bridge", h.wsBridgeHandler)
-
-	h.log.Info("Bridge mode started.")
-	h.log.Info("The frontend will connect automatically.")
-
-	err := h.server.ListenAndServe()
-	if err != nil && err != http.ErrServerClosed {
-		h.log.Fatal(err.Error())
-	}
-	return err
-}
-
-// NewBinding creates a new binding with the frontend
-func (h *Bridge) NewBinding(methodName string) error {
-	h.bindingCache = append(h.bindingCache, methodName)
-	return nil
-}
-
-// SelectFile is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) SelectFile() string {
-	h.log.Warn("SelectFile() unsupported in bridge mode")
-	return ""
-}
-
-// SelectDirectory is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) SelectDirectory() string {
-	h.log.Warn("SelectDirectory() unsupported in bridge mode")
-	return ""
-}
-
-// SelectSaveFile is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) SelectSaveFile() string {
-	h.log.Warn("SelectSaveFile() unsupported in bridge mode")
-	return ""
-}
-
-// Callback sends a callback to the frontend
-func (h *Bridge) Callback(data string) error {
-	return h.evalJS(data, callbackMessage)
-}
-
-// NotifyEvent notifies the frontend of an event
-func (h *Bridge) NotifyEvent(event *messages.EventData) error {
-
-	// Look out! Nils about!
-	var err error
-	if event == nil {
-		err = fmt.Errorf("Sent nil event to renderer.webViewRenderer")
-		h.log.Error(err.Error())
-		return err
-	}
-
-	// Default data is a blank array
-	data := []byte("[]")
-
-	// Process event data
-	if event.Data != nil {
-		// Marshall the data
-		data, err = json.Marshal(event.Data)
-		if err != nil {
-			h.log.Errorf("Cannot unmarshall JSON data in event: %s ", err.Error())
-			return err
-		}
-	}
-
-	message := fmt.Sprintf("window.wails._.Notify('%s','%s')", event.Name, data)
-	return h.evalJS(message, notifyMessage)
-}
-
-// SetColour is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) SetColour(colour string) error {
-	h.log.WarnFields("SetColour ignored for Bridge more", logger.Fields{"col": colour})
-	return nil
-}
-
-// Fullscreen is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) Fullscreen() {
-	h.log.Warn("Fullscreen() unsupported in bridge mode")
-}
-
-// UnFullscreen is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) UnFullscreen() {
-	h.log.Warn("UnFullscreen() unsupported in bridge mode")
-}
-
-// SetTitle is currently unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) SetTitle(title string) {
-	h.log.WarnFields("SetTitle() unsupported in bridge mode", logger.Fields{"title": title})
-}
-
-// Close is unsupported for Bridge but required
-// for the Renderer interface
-func (h *Bridge) Close() {
-	h.log.Debug("Shutting down")
-	err := h.server.Close()
-	if err != nil {
-		h.log.Errorf(err.Error())
-	}
 }

lib/renderer/bridge/bridge.go

@@ -0,0 +1,214 @@
+package renderer
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"sync"
+
+	"github.com/gorilla/websocket"
+	"github.com/wailsapp/wails/lib/interfaces"
+	"github.com/wailsapp/wails/lib/logger"
+	"github.com/wailsapp/wails/lib/messages"
+)
+
+type messageType int
+
+const (
+	jsMessage messageType = iota
+	cssMessage
+	htmlMessage
+	notifyMessage
+	bindingMessage
+	callbackMessage
+	wailsRuntimeMessage
+)
+
+func (m messageType) toString() string {
+	return [...]string{"j", "s", "h", "n", "b", "c", "w"}[m]
+}
+
+// Bridge is a backend that opens a local web server
+// and renders the files over a websocket
+type Bridge struct {
+	// Common
+	log          *logger.CustomLogger
+	ipcManager   interfaces.IPCManager
+	appConfig    interfaces.AppConfig
+	eventManager interfaces.EventManager
+	bindingCache []string
+
+	// Bridge specific
+	server *http.Server
+
+	lock     sync.Mutex
+	sessions map[string]session
+}
+
+// Initialise the Bridge Renderer
+func (h *Bridge) Initialise(appConfig interfaces.AppConfig, ipcManager interfaces.IPCManager, eventManager interfaces.EventManager) error {
+	h.sessions = map[string]session{}
+	h.ipcManager = ipcManager
+	h.appConfig = appConfig
+	h.eventManager = eventManager
+	ipcManager.BindRenderer(h)
+	h.log = logger.NewCustomLogger("Bridge")
+	return nil
+}
+
+// EnableConsole not needed for bridge!
+func (h *Bridge) EnableConsole() {
+}
+
+func (h *Bridge) wsBridgeHandler(w http.ResponseWriter, r *http.Request) {
+	conn, err := websocket.Upgrade(w, r, w.Header(), 1024, 1024)
+	if err != nil {
+		http.Error(w, "Could not open websocket connection", http.StatusBadRequest)
+	}
+	h.log.Infof("Connection from frontend accepted [%s].", conn.RemoteAddr().String())
+	h.startSession(conn)
+}
+
+func (h *Bridge) startSession(conn *websocket.Conn) {
+	s := session{
+		conn:         conn,
+		bindingCache: h.bindingCache,
+		ipc:          h.ipcManager,
+		log:          h.log,
+		eventManager: h.eventManager,
+	}
+
+	conn.SetCloseHandler(func(int, string) error {
+		h.log.Infof("Connection dropped [%s].", s.Identifier())
+		h.eventManager.Emit("wails:bridge:session:closed", s.Identifier())
+		h.lock.Lock()
+		defer h.lock.Unlock()
+		delete(h.sessions, s.Identifier())
+		return nil
+	})
+
+	h.lock.Lock()
+	defer h.lock.Unlock()
+	go s.start(len(h.sessions) == 0)
+	h.sessions[s.Identifier()] = s
+}
+
+// Run the app in Bridge mode!
+func (h *Bridge) Run() error {
+	h.server = &http.Server{Addr: ":34115"}
+	http.HandleFunc("/bridge", h.wsBridgeHandler)
+
+	h.log.Info("Bridge mode started.")
+	h.log.Info("The frontend will connect automatically.")
+
+	err := h.server.ListenAndServe()
+	if err != nil && err != http.ErrServerClosed {
+		h.log.Fatal(err.Error())
+	}
+	return err
+}
+
+// NewBinding creates a new binding with the frontend
+func (h *Bridge) NewBinding(methodName string) error {
+	h.bindingCache = append(h.bindingCache, methodName)
+	return nil
+}
+
+// SelectFile is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) SelectFile() string {
+	h.log.Warn("SelectFile() unsupported in bridge mode")
+	return ""
+}
+
+// SelectDirectory is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) SelectDirectory() string {
+	h.log.Warn("SelectDirectory() unsupported in bridge mode")
+	return ""
+}
+
+// SelectSaveFile is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) SelectSaveFile() string {
+	h.log.Warn("SelectSaveFile() unsupported in bridge mode")
+	return ""
+}
+
+// NotifyEvent notifies the frontend of an event
+func (h *Bridge) NotifyEvent(event *messages.EventData) error {
+
+	// Look out! Nils about!
+	var err error
+	if event == nil {
+		err = fmt.Errorf("Sent nil event to renderer.webViewRenderer")
+		h.log.Error(err.Error())
+		return err
+	}
+
+	// Default data is a blank array
+	data := []byte("[]")
+
+	// Process event data
+	if event.Data != nil {
+		// Marshall the data
+		data, err = json.Marshal(event.Data)
+		if err != nil {
+			h.log.Errorf("Cannot unmarshall JSON data in event: %s ", err.Error())
+			return err
+		}
+	}
+
+	message := fmt.Sprintf("window.wails._.Notify('%s','%s')", event.Name, data)
+	dead := []session{}
+	for _, session := range h.sessions {
+		err := session.evalJS(message, notifyMessage)
+		if err != nil {
+			h.log.Debugf("Failed to send message to %s - Removing listener : %v", session.Identifier(), err)
+			h.log.Infof("Connection from [%v] unresponsive - dropping", session.Identifier())
+			dead = append(dead, session)
+		}
+	}
+	h.lock.Lock()
+	defer h.lock.Unlock()
+	for _, session := range dead {
+		delete(h.sessions, session.Identifier())
+	}
+
+	return nil
+}
+
+// SetColour is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) SetColour(colour string) error {
+	h.log.WarnFields("SetColour ignored for Bridge more", logger.Fields{"col": colour})
+	return nil
+}
+
+// Fullscreen is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) Fullscreen() {
+	h.log.Warn("Fullscreen() unsupported in bridge mode")
+}
+
+// UnFullscreen is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) UnFullscreen() {
+	h.log.Warn("UnFullscreen() unsupported in bridge mode")
+}
+
+// SetTitle is currently unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) SetTitle(title string) {
+	h.log.WarnFields("SetTitle() unsupported in bridge mode", logger.Fields{"title": title})
+}
+
+// Close is unsupported for Bridge but required
+// for the Renderer interface
+func (h *Bridge) Close() {
+	h.log.Debug("Shutting down")
+	err := h.server.Close()
+	if err != nil {
+		h.log.Errorf(err.Error())
+	}
+}

lib/renderer/bridge/session.go

@@ -0,0 +1,90 @@
+package renderer
+
+import (
+	"sync"
+
+	"github.com/gorilla/websocket"
+	"github.com/leaanthony/mewn"
+	"github.com/wailsapp/wails/lib/interfaces"
+	"github.com/wailsapp/wails/lib/logger"
+)
+
+// TODO Move this back into bridge.go
+
+// session represents a single websocket session
+type session struct {
+	bindingCache []string
+	conn         *websocket.Conn
+	eventManager interfaces.EventManager
+	log          *logger.CustomLogger
+	ipc          interfaces.IPCManager
+
+	// Mutex for writing to the socket
+	lock sync.Mutex
+}
+
+// Identifier returns a string identifier for the remote connection.
+// Taking the form of the client's <ip address>:<port>.
+func (s *session) Identifier() string {
+	if s.conn != nil {
+		return s.conn.RemoteAddr().String()
+	}
+	return ""
+}
+
+func (s *session) sendMessage(msg string) error {
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	if err := s.conn.WriteMessage(websocket.TextMessage, []byte(msg)); err != nil {
+		s.log.Debug(err.Error())
+		return err
+	}
+
+	return nil
+}
+
+func (s *session) start(firstSession bool) {
+	s.log.Infof("Connected to frontend.")
+
+	wailsRuntime := mewn.String("../../runtime/assets/wails.js")
+	s.evalJS(wailsRuntime, wailsRuntimeMessage)
+
+	// Inject bindings
+	for _, binding := range s.bindingCache {
+		s.evalJS(binding, bindingMessage)
+	}
+	s.eventManager.Emit("wails:bridge:session:started", s.Identifier())
+
+	// Emit that everything is loaded and ready
+	if firstSession {
+		s.eventManager.Emit("wails:ready")
+	}
+
+	for {
+		messageType, buffer, err := s.conn.ReadMessage()
+		if messageType == -1 {
+			return
+		}
+		if err != nil {
+			s.log.Errorf("Error reading message: %v", err)
+			continue
+		}
+
+		s.log.Debugf("Got message: %#v\n", string(buffer))
+
+		s.ipc.Dispatch(string(buffer), s.Callback)
+	}
+}
+
+// Callback sends a callback to the frontend
+func (s *session) Callback(data string) error {
+	return s.evalJS(data, callbackMessage)
+}
+
+func (s *session) evalJS(js string, mtype messageType) error {
+
+	// Prepend message type to message
+	return s.sendMessage(mtype.toString() + js)
+
+}

lib/renderer/webview.go

@@ -58,7 +58,7 @@ func (w *WebView) Initialise(config interfaces.AppConfig, ipc interfaces.IPCMana
 		URL:       config.GetDefaultHTML(),
 		Debug:     !config.GetDisableInspector(),
 		ExternalInvokeCallback: func(_ wv.WebView, message string) {
-			w.ipc.Dispatch(message)
+			w.ipc.Dispatch(message, w.callback)
 		},
 	})
 
@@ -299,8 +299,8 @@ func (w *WebView) SelectSaveFile() string {
 	return result
 }
 
-// Callback sends a callback to the frontend
+// callback sends a callback to the frontend
-func (w *WebView) Callback(data string) error {
+func (w *WebView) callback(data string) error {
 	callbackCMD := fmt.Sprintf("window.wails._.Callback('%s');", data)
 	return w.evalJS(callbackCMD)
 }