Feature: AssetServer Runtime (#2335)

* Tidy up runtime JS

* Initial implementation of runtime over http

* Update runtime deps. Fix test task.

* Support Clipboard.
Message Processor refactor.

* Add `Window.Screen()`
Clipboard `GetText` -> `Text`

* Support most dialogs
Better JS->Go object mapping
Implement Go->JS callback mechanism
Rename `window.runtime` -> `window.wails` to better reflect the Go API

* Support SaveFile dialog

* Remove go.work

* Tidy up

* Event->CustomEvent to prevent potential clash with native JS Event object
Support Eventing

* Support application calls

* Support logging

* Support named windows
Remove debug info

* Update v3 changes

v2/pkg/assetserver/assetserver.go

@@ -14,6 +14,7 @@ import (
 const (
 	runtimeJSPath = "/wails/runtime.js"
 	ipcJSPath     = "/wails/ipc.js"
+	runtimePath   = "/wails/runtime"
 )
 
 type RuntimeAssets interface {
@@ -22,6 +23,10 @@ type RuntimeAssets interface {
 	RuntimeDesktopJS() []byte
 }
 
+type RuntimeHandler interface {
+	HandleRuntimeCall(w http.ResponseWriter, r *http.Request)
+}
+
 type AssetServer struct {
 	handler   http.Handler
 	wsHandler http.Handler
@@ -34,6 +39,9 @@ type AssetServer struct {
 	servingFromDisk     bool
 	appendSpinnerToBody bool
 
+	// Use http based runtime
+	runtimeHandler RuntimeHandler
+
 	assetServerWebView
 }
 
@@ -77,6 +85,10 @@ func NewAssetServerWithHandler(handler http.Handler, bindingsJSON string, servin
 	return result, nil
 }
 
+func (d *AssetServer) UseRuntimeHandler(handler RuntimeHandler) {
+	d.runtimeHandler = handler
+}
+
 func (d *AssetServer) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 	if isWebSocket(req) {
 		// Forward WebSockets to the distinct websocket handler if it exists
@@ -122,6 +134,13 @@ func (d *AssetServer) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 	case runtimeJSPath:
 		d.writeBlob(rw, path, d.runtimeJS)
 
+	case runtimePath:
+		if d.runtimeHandler != nil {
+			d.runtimeHandler.HandleRuntimeCall(rw, req)
+		} else {
+			d.handler.ServeHTTP(rw, req)
+		}
+
 	case ipcJSPath:
 		content := d.runtime.DesktopIPC()
 		if d.ipcJS != nil {