Feature: set browser path (#1448)

* Added option to specify webview2 path

* Added `manual` webview strategy

* Update documentation

* Fixed build with manual tag

* Check for browser directory existence

* Added version check for manually specified webview, removed fallback for installed webview in manual strategy

* Update WebviewBrowserPath documentation

* Replaced deprecated StringToUTF16Ptr

* Return on error

* Removed manual strategy, return error in wv2installer for fixed runtime

* Removed manual strategy from CLI

v2/internal/frontend/desktop/windows/frontend.go

@@ -352,8 +352,9 @@ func (f *Frontend) Quit() {
 func (f *Frontend) setupChromium() {
 	chromium := edge.NewChromium()
 	f.chromium = chromium
-	if opts := f.frontendOptions.Windows; opts != nil && opts.WebviewUserDataPath != "" {
+	if opts := f.frontendOptions.Windows; opts != nil {
 		chromium.DataPath = opts.WebviewUserDataPath
+		chromium.BrowserPath = opts.WebviewBrowserPath
 	}
 	chromium.MessageCallback = f.processMessage
 	chromium.WebResourceRequestedCallback = f.processRequest

v2/internal/frontend/desktop/windows/go-webview2/pkg/edge/chromium.go

@@ -4,6 +4,7 @@
 package edge
 
 import (
+	"errors"
 	"log"
 	"os"
 	"path/filepath"
@@ -30,8 +31,9 @@ type Chromium struct {
 	environment *ICoreWebView2Environment
 
 	// Settings
-	Debug    bool
-	DataPath string
+	Debug       bool
+	DataPath    string
+	BrowserPath string
 
 	// permissions
 	permissions      map[CoreWebView2PermissionKind]CoreWebView2PermissionState
@@ -84,7 +86,27 @@ func (e *Chromium) Embed(hwnd uintptr) bool {
 		dataPath = filepath.Join(os.Getenv("AppData"), currentExeName)
 	}
 
-	res, err := createCoreWebView2EnvironmentWithOptions(nil, windows.StringToUTF16Ptr(dataPath), 0, e.envCompleted)
+	var browserPathPtr *uint16 = nil
+	if e.BrowserPath != "" {
+		if _, err := os.Stat(e.BrowserPath); !errors.Is(err, os.ErrNotExist) {
+			browserPathPtr, err = windows.UTF16PtrFromString(e.BrowserPath)
+			if err != nil {
+				log.Printf("Error calling UTF16PtrFromString for %s: %v", e.BrowserPath, err)
+				return false
+			}
+		} else {
+			log.Printf("Browser path %s does not exist", e.BrowserPath)
+			return false
+		}
+	}
+
+	dataPathPtr, err := windows.UTF16PtrFromString(dataPath)
+	if err != nil {
+		log.Printf("Error calling UTF16PtrFromString for %s: %v", dataPath, err)
+		return false
+	}
+
+	res, err := createCoreWebView2EnvironmentWithOptions(browserPathPtr, dataPathPtr, 0, e.envCompleted)
 	if err != nil {
 		log.Printf("Error calling Webview2Loader: %v", err)
 		return false

v2/internal/frontend/desktop/windows/go-webview2/webviewloader/module.go

@@ -54,17 +54,26 @@ func CompareBrowserVersions(v1 string, v2 string) (int, error) {
 	return int(result), nil
 }
 
-// GetInstalledVersion returns the installed version of the webview2 runtime.
+// GetWebviewVersion returns version of the webview2 runtime.
+// If path is empty, it will try to find installed webview2 is the system.
 // If there is no version installed, a blank string is returned.
-func GetInstalledVersion() (string, error) {
+func GetWebviewVersion(path string) (string, error) {
 	err := loadFromMemory()
 	if err != nil {
 		return "", err
 	}
 
+	var browserPath *uint16 = nil
+	if path != "" {
+		browserPath, err = windows.UTF16PtrFromString(path)
+		if err != nil {
+			return "", fmt.Errorf("error calling UTF16PtrFromString for %s: %v", path, err)
+		}
+	}
+
 	var result *uint16
 	res, _, err := memGetAvailableCoreWebView2BrowserVersionString.Call(
-		uint64(uintptr(unsafe.Pointer(nil))),
+		uint64(uintptr(unsafe.Pointer(browserPath))),
 		uint64(uintptr(unsafe.Pointer(&result))))
 
 	if res != 0 {

v2/internal/system/system_windows.go

@@ -28,8 +28,7 @@ func (i *Info) discover() error {
 }
 
 func checkWebView2() *packagemanager.Dependancy {
-
-	version, _ := webviewloader.GetInstalledVersion()
+	version, _ := webviewloader.GetWebviewVersion("")
 	installed := version != ""
 
 	return &packagemanager.Dependancy{

v2/internal/wv2installer/wv2installer.go

@@ -3,6 +3,7 @@
 package wv2installer
 
 import (
+	"fmt"
 	"github.com/wailsapp/wails/v2/internal/frontend/desktop/windows/go-webview2/webviewloader"
 	"github.com/wailsapp/wails/v2/pkg/options"
 	"github.com/wailsapp/wails/v2/pkg/options/windows"
@@ -24,7 +25,14 @@ func Process(appoptions *options.App) (string, error) {
 	}
 
 	installStatus := needsInstalling
-	installedVersion, err := webviewloader.GetInstalledVersion()
+
+	// Override version check for manually specified webview path if present
+	var webviewPath = ""
+	if opts := appoptions.Windows; opts != nil && opts.WebviewBrowserPath != "" {
+		webviewPath = opts.WebviewBrowserPath
+	}
+
+	installedVersion, err := webviewloader.GetWebviewVersion(webviewPath)
 	if err != nil {
 		return "", err
 	}
@@ -42,5 +50,10 @@ func Process(appoptions *options.App) (string, error) {
 		}
 	}
 
+	// Force error strategy if webview is manually specified
+	if webviewPath != "" {
+		return installedVersion, fmt.Errorf(messages.InvalidFixedWebview2)
+	}
+
 	return installedVersion, doInstallationStrategy(installStatus, messages)
 }

v2/pkg/options/windows/windows.go

@@ -12,6 +12,7 @@ type Messages struct {
 	DownloadPage         string
 	PressOKToInstall     string
 	ContactAdmin         string
+	InvalidFixedWebview2 string
 }
 
 const (
@@ -71,6 +72,9 @@ type Options struct {
 	// If the path is not valid, a messagebox will be displayed with the error and the app will exit with error code.
 	WebviewUserDataPath string
 
+	// Path to the directory with WebView2 executables. If empty WebView2 installed in the system will be used.
+	WebviewBrowserPath string
+
 	// Dark/Light or System Default Theme
 	Theme Theme
 
@@ -104,5 +108,6 @@ func DefaultMessages() *Messages {
 		DownloadPage:         "This application requires the WebView2 runtime. Press OK to open the download page. Minimum version required: ",
 		PressOKToInstall:     "Press Ok to install.",
 		ContactAdmin:         "The WebView2 runtime is required to run this application. Please contact your system administrator.",
+		InvalidFixedWebview2: "The WebView2 runtime is manually specified, but It is not valid. Check minimum required version and webview2 path.",
 	}
 }

website/docs/guides/windows.mdx

@@ -35,3 +35,20 @@ up to the user.
 ### Error
 
 If no suitable runtime is found, an error is given to the user and no further action taken.
+
+## Fixed version runtime
+
+Another way of dealing with webview2 dependency is shipping it yourself.
+You can download [fixed version runtime](https://developer.microsoft.com/ru-ru/microsoft-edge/webview2/#download-section) and bundle or download it with your application.
+
+Also, you should specify path to fixed version of webview2 runtime in the `windows.Options` structure when launching wails.
+
+```go
+	wails.Run(&options.App{
+		Windows: &windows.Options{
+			WebviewBrowserPath:  "",
+		},
+	})
+```
+
+Note: When `WebviewBrowserPath` is specified, `error` strategy will be forced in case of minimal required version mismatch or invalid path to a runtime.

website/docs/reference/options.mdx

@@ -48,6 +48,7 @@ func main() {
             DisableWindowIcon:                 false,
             DisableFramelessWindowDecorations: false,
             WebviewUserDataPath:               "",
+            WebviewBrowserPath:                "",
             Theme:                             windows.SystemDefault,
             CustomTheme: &windows.ThemeSettings{
                 DarkModeTitleBar:   windows.RGB(20, 20, 20),
@@ -430,6 +431,19 @@ Type: string
 
 This defines the path where the WebView2 stores the user data. If empty `%APPDATA%\[BinaryName.exe]` will be used.
 
+### WebviewBrowserPath
+
+Name: WebviewBrowserPath
+
+Type: string
+
+This defines the path to a directory with WebView2 executable files and libraries. If empty, webview2 installed in the system will be used.
+
+Important information about distribution of fixed version runtime:
+- [How to get and extract runtime](https://docs.microsoft.com/en-us/microsoft-edge/webview2/concepts/distribution#details-about-the-fixed-version-runtime-distribution-mode)
+- [Known issues for fixed version](https://docs.microsoft.com/en-us/microsoft-edge/webview2/concepts/distribution#known-issues-for-fixed-version)
+- [The path of fixed version of the WebView2 Runtime should not contain \Edge\Application\.](https://docs.microsoft.com/en-us/microsoft-edge/webview2/reference/win32/webview2-idl?view=webview2-1.0.1245.22#createcorewebview2environmentwithoptions)
+
 ### Theme
 
 Name: Theme