v2.0.0-alpha.19

v2/cmd/wails/internal/commands/update/update.go

@@ -0,0 +1,164 @@
+package update
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"os"
+
+	"github.com/wailsapp/wails/v2/internal/shell"
+
+	"github.com/wailsapp/wails/v2/internal/github"
+
+	"github.com/leaanthony/clir"
+	"github.com/wailsapp/wails/v2/pkg/clilogger"
+)
+
+// AddSubcommand adds the `init` command for the Wails application
+func AddSubcommand(app *clir.Cli, w io.Writer, currentVersion string) error {
+
+	command := app.NewSubCommand("update", "Update the Wails CLI")
+	command.LongDescription(`This command allows you to update your version of Wails.`)
+
+	// Setup flags
+	var prereleaseRequired bool
+	command.BoolFlag("pre", "Update to latest Prerelease", &prereleaseRequired)
+
+	var specificVersion string
+	command.StringFlag("version", "Install a specific version (Overrides other flags)", &specificVersion)
+
+	command.Action(func() error {
+
+		// Create logger
+		logger := clilogger.New(w)
+
+		// Print banner
+		app.PrintBanner()
+		logger.Println("Checking for updates...")
+
+		var desiredVersion *github.SemanticVersion
+		var err error
+		var valid bool
+
+		if len(specificVersion) > 0 {
+			// Check if this is a valid version
+			valid, err = github.IsValidTag(specificVersion)
+			if err == nil {
+				if !valid {
+					err = fmt.Errorf("version '%s' is invalid", specificVersion)
+				} else {
+					desiredVersion, err = github.NewSemanticVersion(specificVersion)
+				}
+			}
+		} else {
+			if prereleaseRequired {
+				desiredVersion, err = github.GetLatestPreRelease()
+			} else {
+				desiredVersion, err = github.GetLatestStableRelease()
+			}
+		}
+		if err != nil {
+			return err
+		}
+		fmt.Println()
+
+		fmt.Println("    Current Version : " + currentVersion)
+
+		if len(specificVersion) > 0 {
+			fmt.Printf("    Desired Version : v%s\n", desiredVersion)
+		} else {
+			if prereleaseRequired {
+				fmt.Printf("  Latest Prerelease : v%s\n", desiredVersion)
+			} else {
+				fmt.Printf("     Latest Release : v%s\n", desiredVersion)
+			}
+		}
+
+		return updateToVersion(logger, desiredVersion, len(specificVersion) > 0, currentVersion)
+	})
+
+	return nil
+}
+
+func updateToVersion(logger *clilogger.CLILogger, targetVersion *github.SemanticVersion, force bool, currentVersion string) error {
+
+	var targetVersionString = "v" + targetVersion.String()
+
+	// Early exit
+	if targetVersionString == currentVersion {
+		logger.Println("Looks like you're up to date!")
+		return nil
+	}
+
+	var desiredVersion string
+
+	if !force {
+
+		compareVersion := currentVersion
+
+		currentVersion, err := github.NewSemanticVersion(compareVersion)
+		if err != nil {
+			return err
+		}
+
+		var success bool
+
+		// Release -> Pre-Release = Massage current version to prerelease format
+		if targetVersion.IsPreRelease() && currentVersion.IsRelease() {
+			testVersion, err := github.NewSemanticVersion(compareVersion + "-0")
+			if err != nil {
+				return err
+			}
+			success, _ = targetVersion.IsGreaterThan(testVersion)
+		}
+		// Pre-Release -> Release = Massage target version to prerelease format
+		if targetVersion.IsRelease() && currentVersion.IsPreRelease() {
+			// We are ok with greater than or equal
+			mainversion := currentVersion.MainVersion()
+			targetVersion, err = github.NewSemanticVersion(targetVersion.String())
+			if err != nil {
+				return err
+			}
+			success, _ = targetVersion.IsGreaterThanOrEqual(mainversion)
+		}
+
+		// Release -> Release = Standard check
+		if (targetVersion.IsRelease() && currentVersion.IsRelease()) ||
+			(targetVersion.IsPreRelease() && currentVersion.IsPreRelease()) {
+
+			success, _ = targetVersion.IsGreaterThan(currentVersion)
+		}
+
+		// Compare
+		if !success {
+			logger.Println("Error: The requested version is lower than the current version.")
+			logger.Println("If this is what you really want to do, use `wails update -version %s`", targetVersionString)
+			return nil
+		}
+
+		desiredVersion = "v" + targetVersion.String()
+
+	} else {
+		desiredVersion = "v" + targetVersion.String()
+	}
+
+	fmt.Println()
+	logger.Print("Installing Wails " + desiredVersion + "...")
+
+	// Run command in non module directory
+	homeDir, err := os.UserHomeDir()
+	if err != nil {
+		log.Fatal("Cannot find home directory! Please file a bug report!")
+	}
+
+	sout, serr, err := shell.RunCommand(homeDir, "go", "get", "github.com/wailsapp/wails/v2/cmd/wails@"+desiredVersion)
+	if err != nil {
+		logger.Println("Failed.")
+		logger.Println(sout + `\n` + serr)
+		return err
+	}
+	fmt.Println()
+	logger.Println("Wails updated to " + desiredVersion)
+
+	return nil
+}

v2/cmd/wails/main.go

@@ -3,6 +3,8 @@ package main
 import (
 	"os"
 
+	"github.com/wailsapp/wails/v2/cmd/wails/internal/commands/update"
+
 	"github.com/leaanthony/clir"
 	"github.com/wailsapp/wails/v2/cmd/wails/internal/commands/build"
 	"github.com/wailsapp/wails/v2/cmd/wails/internal/commands/debug"
@@ -48,6 +50,11 @@ func main() {
 		fatal(err.Error())
 	}
 
+	err = update.AddSubcommand(app, os.Stdout, version)
+	if err != nil {
+		fatal(err.Error())
+	}
+
 	err = app.Run()
 	if err != nil {
 		println("\n\nERROR: " + err.Error())

v2/cmd/wails/version.go

@@ -1,3 +1,3 @@
 package main
 
-var version = "v2.0.0-alpha.16"
+var version = "v2.0.0-alpha.19"

v2/go.mod

@@ -3,6 +3,7 @@ module github.com/wailsapp/wails/v2
 go 1.15
 
 require (
+	github.com/Masterminds/semver v1.5.0
 	github.com/davecgh/go-spew v1.1.1
 	github.com/fatih/structtag v1.2.0
 	github.com/fsnotify/fsnotify v1.4.9

v2/go.sum

@@ -1,3 +1,5 @@
+github.com/Masterminds/semver v1.5.0 h1:H65muMkzWKEuNDnfl9d70GUjFniHKHRbFPGBuZ3QEww=
+github.com/Masterminds/semver v1.5.0/go.mod h1:MB6lktGJrhw8PrUyiEoblNEGEQ+RzHPF078ddwwvV3Y=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

v2/internal/app/desktop.go

@@ -81,12 +81,15 @@ func CreateApp(appoptions *options.App) (*App, error) {
 
 	window := ffenestri.NewApplicationWithConfig(appoptions, myLogger, menuManager)
 
+	// Create binding exemptions - Ugly hack. There must be a better way
+	bindingExemptions := []interface{}{appoptions.Startup, appoptions.Shutdown}
+
 	result := &App{
 		appType:          "desktop",
 		window:           window,
 		servicebus:       servicebus.New(myLogger),
 		logger:           myLogger,
-		bindings:         binding.NewBindings(myLogger, appoptions.Bind),
+		bindings:         binding.NewBindings(myLogger, appoptions.Bind, bindingExemptions),
 		menuManager:      menuManager,
 		startupCallback:  appoptions.Startup,
 		shutdownCallback: appoptions.Shutdown,

v2/internal/binding/binding.go

@@ -2,23 +2,38 @@ package binding
 
 import (
 	"fmt"
+	"reflect"
+	"runtime"
 	"strings"
 
+	"github.com/leaanthony/slicer"
+
 	"github.com/wailsapp/wails/v2/internal/logger"
 )
 
 type Bindings struct {
-	db     *DB
+	db         *DB
-	logger logger.CustomLogger
+	logger     logger.CustomLogger
+	exemptions slicer.StringSlicer
 }
 
 // NewBindings returns a new Bindings object
-func NewBindings(logger *logger.Logger, structPointersToBind []interface{}) *Bindings {
+func NewBindings(logger *logger.Logger, structPointersToBind []interface{}, exemptions []interface{}) *Bindings {
 	result := &Bindings{
 		db:     newDB(),
 		logger: logger.CustomLogger("Bindings"),
 	}
 
+	for _, exemption := range exemptions {
+		if exemptions == nil {
+			continue
+		}
+		name := runtime.FuncForPC(reflect.ValueOf(exemption).Pointer()).Name()
+		// Yuk yuk yuk! Is there a better way?
+		name = strings.TrimSuffix(name, "-fm")
+		result.exemptions.Add(name)
+	}
+
 	// Add the structs to bind
 	for _, ptr := range structPointersToBind {
 		err := result.Add(ptr)
@@ -33,7 +48,7 @@ func NewBindings(logger *logger.Logger, structPointersToBind []interface{}) *Bin
 // Add the given struct methods to the Bindings
 func (b *Bindings) Add(structPtr interface{}) error {
 
-	methods, err := getMethods(structPtr)
+	methods, err := b.getMethods(structPtr)
 	if err != nil {
 		return fmt.Errorf("cannot bind value to app: %s", err.Error())
 	}
@@ -46,7 +61,6 @@ func (b *Bindings) Add(structPtr interface{}) error {
 
 		// Add it as a regular method
 		b.db.AddMethod(packageName, structName, methodName, method)
-
 	}
 	return nil
 }

v2/internal/binding/boundMethod.go

@@ -30,6 +30,9 @@ func (b *BoundMethod) OutputCount() int {
 func (b *BoundMethod) ParseArgs(args []json.RawMessage) ([]interface{}, error) {
 
 	result := make([]interface{}, b.InputCount())
+	if len(args) != b.InputCount() {
+		return nil, fmt.Errorf("received %d arguments to method '%s', expected %d", len(args), b.Name, b.InputCount())
+	}
 	for index, arg := range args {
 		typ := b.Inputs[index].reflectType
 		inputValue := reflect.New(typ).Interface()

v2/internal/binding/reflect.go

@@ -23,7 +23,7 @@ func isStruct(value interface{}) bool {
 	return reflect.ValueOf(value).Kind() == reflect.Struct
 }
 
-func getMethods(value interface{}) ([]*BoundMethod, error) {
+func (b *Bindings) getMethods(value interface{}) ([]*BoundMethod, error) {
 
 	// Create result placeholder
 	var result []*BoundMethod
@@ -56,6 +56,11 @@ func getMethods(value interface{}) ([]*BoundMethod, error) {
 		fullMethodName := baseName + "." + methodName
 		method := structValue.MethodByName(methodName)
 
+		methodReflectName := runtime.FuncForPC(methodDef.Func.Pointer()).Name()
+		if b.exemptions.Contains(methodReflectName) {
+			continue
+		}
+
 		// Create new method
 		boundMethod := &BoundMethod{
 			Name:     fullMethodName,

v2/internal/deepcopy/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Joel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

v2/internal/deepcopy/deepcopy.go

@@ -0,0 +1,125 @@
+// deepcopy makes deep copies of things. A standard copy will copy the
+// pointers: deep copy copies the values pointed to.  Unexported field
+// values are not copied.
+//
+// Copyright (c)2014-2016, Joel Scoble (github.com/mohae), all rights reserved.
+// License: MIT, for more details check the included LICENSE file.
+package deepcopy
+
+import (
+	"reflect"
+	"time"
+)
+
+// Interface for delegating copy process to type
+type Interface interface {
+	DeepCopy() interface{}
+}
+
+// Iface is an alias to Copy; this exists for backwards compatibility reasons.
+func Iface(iface interface{}) interface{} {
+	return Copy(iface)
+}
+
+// Copy creates a deep copy of whatever is passed to it and returns the copy
+// in an interface{}.  The returned value will need to be asserted to the
+// correct type.
+func Copy(src interface{}) interface{} {
+	if src == nil {
+		return nil
+	}
+
+	// Make the interface a reflect.Value
+	original := reflect.ValueOf(src)
+
+	// Make a copy of the same type as the original.
+	cpy := reflect.New(original.Type()).Elem()
+
+	// Recursively copy the original.
+	copyRecursive(original, cpy)
+
+	// Return the copy as an interface.
+	return cpy.Interface()
+}
+
+// copyRecursive does the actual copying of the interface. It currently has
+// limited support for what it can handle. Add as needed.
+func copyRecursive(original, cpy reflect.Value) {
+	// check for implement deepcopy.Interface
+	if original.CanInterface() {
+		if copier, ok := original.Interface().(Interface); ok {
+			cpy.Set(reflect.ValueOf(copier.DeepCopy()))
+			return
+		}
+	}
+
+	// handle according to original's Kind
+	switch original.Kind() {
+	case reflect.Ptr:
+		// Get the actual value being pointed to.
+		originalValue := original.Elem()
+
+		// if  it isn't valid, return.
+		if !originalValue.IsValid() {
+			return
+		}
+		cpy.Set(reflect.New(originalValue.Type()))
+		copyRecursive(originalValue, cpy.Elem())
+
+	case reflect.Interface:
+		// If this is a nil, don't do anything
+		if original.IsNil() {
+			return
+		}
+		// Get the value for the interface, not the pointer.
+		originalValue := original.Elem()
+
+		// Get the value by calling Elem().
+		copyValue := reflect.New(originalValue.Type()).Elem()
+		copyRecursive(originalValue, copyValue)
+		cpy.Set(copyValue)
+
+	case reflect.Struct:
+		t, ok := original.Interface().(time.Time)
+		if ok {
+			cpy.Set(reflect.ValueOf(t))
+			return
+		}
+		// Go through each field of the struct and copy it.
+		for i := 0; i < original.NumField(); i++ {
+			// The Type's StructField for a given field is checked to see if StructField.PkgPath
+			// is set to determine if the field is exported or not because CanSet() returns false
+			// for settable fields.  I'm not sure why.  -mohae
+			if original.Type().Field(i).PkgPath != "" {
+				continue
+			}
+			copyRecursive(original.Field(i), cpy.Field(i))
+		}
+
+	case reflect.Slice:
+		if original.IsNil() {
+			return
+		}
+		// Make a new slice and copy each element.
+		cpy.Set(reflect.MakeSlice(original.Type(), original.Len(), original.Cap()))
+		for i := 0; i < original.Len(); i++ {
+			copyRecursive(original.Index(i), cpy.Index(i))
+		}
+
+	case reflect.Map:
+		if original.IsNil() {
+			return
+		}
+		cpy.Set(reflect.MakeMap(original.Type()))
+		for _, key := range original.MapKeys() {
+			originalValue := original.MapIndex(key)
+			copyValue := reflect.New(originalValue.Type()).Elem()
+			copyRecursive(originalValue, copyValue)
+			copyKey := Copy(key.Interface())
+			cpy.SetMapIndex(reflect.ValueOf(copyKey), copyValue)
+		}
+
+	default:
+		cpy.Set(original)
+	}
+}

v2/internal/ffenestri/ffenestri_client.go

@@ -12,9 +12,10 @@ package ffenestri
 import "C"
 
 import (
-	"github.com/wailsapp/wails/v2/pkg/options/dialog"
 	"strconv"
 
+	"github.com/wailsapp/wails/v2/pkg/options/dialog"
+
 	"github.com/wailsapp/wails/v2/internal/logger"
 )
 
@@ -113,6 +114,14 @@ func (c *Client) WindowSize(width int, height int) {
 	C.SetSize(c.app.app, C.int(width), C.int(height))
 }
 
+func (c *Client) WindowSetMinSize(width int, height int) {
+	C.SetMinWindowSize(c.app.app, C.int(width), C.int(height))
+}
+
+func (c *Client) WindowSetMaxSize(width int, height int) {
+	C.SetMaxWindowSize(c.app.app, C.int(width), C.int(height))
+}
+
 // WindowSetColour sets the window colour
 func (c *Client) WindowSetColour(colour int) {
 	r, g, b, a := intToColour(colour)

v2/internal/ffenestri/ffenestri_darwin.c

@@ -140,6 +140,16 @@ void Debug(struct Application *app, const char *message, ... ) {
 	}
 }
 
+void Error(struct Application *app, const char *message, ... ) {
+    const char *temp = concat("LEFfenestri (C) | ", message);
+    va_list args;
+    va_start(args, message);
+    vsnprintf(logbuffer, MAXMESSAGE, temp, args);
+    app->sendMessageToBackend(&logbuffer[0]);
+    MEMFREE(temp);
+    va_end(args);
+}
+
 void Fatal(struct Application *app, const char *message, ... ) {
   const char *temp = concat("LFFfenestri (C) | ", message);
   va_list args;
@@ -246,7 +256,10 @@ void messageHandler(id self, SEL cmd, id contentController, id message) {
 	struct Application *app = (struct Application *)objc_getAssociatedObject(
 							  self, "application");
 	const char *name = (const char *)msg(msg(message, s("name")), s("UTF8String"));
-	if( strcmp(name, "completed") == 0) {
+	if( strcmp(name, "error") == 0 ) {
+	    printf("There was a Javascript error. Please open the devtools for more information.\n");
+	    Show(app);
+	} else if( strcmp(name, "completed") == 0) {
 		// Delete handler
 		msg(app->manager, s("removeScriptMessageHandlerForName:"), str("completed"));
 
@@ -450,6 +463,7 @@ void DestroyApplication(struct Application *app) {
 	msg(app->manager, s("removeScriptMessageHandlerForName:"), str("contextMenu"));
 	msg(app->manager, s("removeScriptMessageHandlerForName:"), str("windowDrag"));
 	msg(app->manager, s("removeScriptMessageHandlerForName:"), str("external"));
+	msg(app->manager, s("removeScriptMessageHandlerForName:"), str("error"));
 
 	// Close main window
 	msg(app->mainWindow, s("close"));
@@ -885,6 +899,20 @@ void setMinMaxSize(struct Application *app)
 	{
 		msg(app->mainWindow, s("setMinSize:"), CGSizeMake(app->minWidth, app->minHeight));
 	}
+
+	// Calculate if window needs resizing
+	int newWidth = app->width;
+	int newHeight = app->height;
+
+	if (app->maxWidth > 0 && app->width > app->maxWidth) newWidth = app->maxWidth;
+	if (app->minWidth > 0 && app->width < app->minWidth) newWidth = app->minWidth;
+	if (app->maxHeight > 0 && app->height > app->maxHeight ) newHeight = app->maxHeight;
+	if (app->minHeight > 0 && app->height < app->minHeight ) newHeight = app->minHeight;
+
+    // If we have any change, resize window
+	if ( newWidth != app->width || newHeight != app->height ) {
+	    SetSize(app, newWidth, newHeight);
+	}
 }
 
 void SetMinWindowSize(struct Application *app, int minWidth, int minHeight)
@@ -1534,6 +1562,7 @@ void Run(struct Application *app, int argc, char **argv) {
 	id manager = msg(config, s("userContentController"));
 	msg(manager, s("addScriptMessageHandler:name:"), app->delegate, str("external"));
 	msg(manager, s("addScriptMessageHandler:name:"), app->delegate, str("completed"));
+	msg(manager, s("addScriptMessageHandler:name:"), app->delegate, str("error"));
 	app->manager = manager;
 
 	id wkwebview = msg(c("WKWebView"), s("alloc"));

v2/internal/ffenestri/menu_darwin.c

@@ -740,7 +740,7 @@ void processMenuItem(Menu *menu, id parentMenu, JsonNode *item) {
     const char *image = getJSONString(item, "Image");
     const char *fontName = getJSONString(item, "FontName");
     const char *RGBA = getJSONString(item, "RGBA");
-    int fontSize = 0;
+    int fontSize = 12;
     getJSONInt(item, "FontSize", &fontSize);
 
     // If we have an accelerator

v2/internal/github/github.go

@@ -0,0 +1,103 @@
+package github
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"sort"
+	"strings"
+)
+
+// GetVersionTags gets the list of tags on the Wails repo
+// It returns a list of sorted tags in descending order
+func GetVersionTags() ([]*SemanticVersion, error) {
+
+	result := []*SemanticVersion{}
+	var err error
+
+	resp, err := http.Get("https://api.github.com/repos/wailsapp/wails/tags")
+	if err != nil {
+		return result, err
+	}
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return result, err
+	}
+
+	data := []map[string]interface{}{}
+	err = json.Unmarshal(body, &data)
+	if err != nil {
+		return result, err
+	}
+
+	// Convert tag data to Version structs
+	for _, tag := range data {
+		version := tag["name"].(string)
+		if !strings.HasPrefix(version, "v2") {
+			continue
+		}
+		semver, err := NewSemanticVersion(version)
+		if err != nil {
+			return result, err
+		}
+		result = append(result, semver)
+	}
+
+	// Reverse Sort
+	sort.Sort(sort.Reverse(SemverCollection(result)))
+
+	return result, err
+}
+
+// GetLatestStableRelease gets the latest stable release on GitHub
+func GetLatestStableRelease() (result *SemanticVersion, err error) {
+
+	tags, err := GetVersionTags()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, tag := range tags {
+		if tag.IsRelease() {
+			return tag, nil
+		}
+	}
+
+	return nil, fmt.Errorf("no release tag found")
+}
+
+// GetLatestPreRelease gets the latest prerelease on GitHub
+func GetLatestPreRelease() (result *SemanticVersion, err error) {
+
+	tags, err := GetVersionTags()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, tag := range tags {
+		if tag.IsPreRelease() {
+			return tag, nil
+		}
+	}
+
+	return nil, fmt.Errorf("no prerelease tag found")
+}
+
+// IsValidTag returns true if the given string is a valid tag
+func IsValidTag(tagVersion string) (bool, error) {
+	if tagVersion[0] == 'v' {
+		tagVersion = tagVersion[1:]
+	}
+	tags, err := GetVersionTags()
+	if err != nil {
+		return false, err
+	}
+
+	for _, tag := range tags {
+		if tag.String() == tagVersion {
+			return true, nil
+		}
+	}
+	return false, nil
+}

v2/internal/github/semver.go

@@ -0,0 +1,106 @@
+package github
+
+import (
+	"fmt"
+
+	"github.com/Masterminds/semver"
+)
+
+// SemanticVersion is a struct containing a semantic version
+type SemanticVersion struct {
+	Version *semver.Version
+}
+
+// NewSemanticVersion creates a new SemanticVersion object with the given version string
+func NewSemanticVersion(version string) (*SemanticVersion, error) {
+	semverVersion, err := semver.NewVersion(version)
+	if err != nil {
+		return nil, err
+	}
+	return &SemanticVersion{
+		Version: semverVersion,
+	}, nil
+}
+
+// IsRelease returns true if it's a release version
+func (s *SemanticVersion) IsRelease() bool {
+	// Limit to v2
+	if s.Version.Major() != 2 {
+		return false
+	}
+	return len(s.Version.Prerelease()) == 0 && len(s.Version.Metadata()) == 0
+}
+
+// IsPreRelease returns true if it's a prerelease version
+func (s *SemanticVersion) IsPreRelease() bool {
+	// Limit to v1
+	if s.Version.Major() != 2 {
+		return false
+	}
+	return len(s.Version.Prerelease()) > 0
+}
+
+func (s *SemanticVersion) String() string {
+	return s.Version.String()
+}
+
+// IsGreaterThan returns true if this version is greater than the given version
+func (s *SemanticVersion) IsGreaterThan(version *SemanticVersion) (bool, error) {
+	// Set up new constraint
+	constraint, err := semver.NewConstraint("> " + version.Version.String())
+	if err != nil {
+		return false, err
+	}
+
+	// Check if the desired one is greater than the requested on
+	success, msgs := constraint.Validate(s.Version)
+	if !success {
+		return false, msgs[0]
+	}
+	return true, nil
+}
+
+// IsGreaterThanOrEqual returns true if this version is greater than or equal the given version
+func (s *SemanticVersion) IsGreaterThanOrEqual(version *SemanticVersion) (bool, error) {
+	// Set up new constraint
+	constraint, err := semver.NewConstraint(">= " + version.Version.String())
+	if err != nil {
+		return false, err
+	}
+
+	// Check if the desired one is greater than the requested on
+	success, msgs := constraint.Validate(s.Version)
+	if !success {
+		return false, msgs[0]
+	}
+	return true, nil
+}
+
+// MainVersion returns the main version of any version+prerelease+metadata
+// EG: MainVersion("1.2.3-pre") => "1.2.3"
+func (s *SemanticVersion) MainVersion() *SemanticVersion {
+	mainVersion := fmt.Sprintf("%d.%d.%d", s.Version.Major(), s.Version.Minor(), s.Version.Patch())
+	result, _ := NewSemanticVersion(mainVersion)
+	return result
+}
+
+// SemverCollection is a collection of SemanticVersion objects
+type SemverCollection []*SemanticVersion
+
+// Len returns the length of a collection. The number of Version instances
+// on the slice.
+func (c SemverCollection) Len() int {
+	return len(c)
+}
+
+// Less is needed for the sort interface to compare two Version objects on the
+// slice. If checks if one is less than the other.
+func (c SemverCollection) Less(i, j int) bool {
+	return c[i].Version.LessThan(c[j].Version)
+}
+
+// Swap is needed for the sort interface to replace the Version objects
+// at two different positions in the slice.
+func (c SemverCollection) Swap(i, j int) {
+	c[i], c[j] = c[j], c[i]
+}

v2/internal/messagedispatcher/dispatchclient.go

@@ -2,6 +2,7 @@ package messagedispatcher
 
 import (
 	"fmt"
+
 	"github.com/wailsapp/wails/v2/internal/logger"
 	"github.com/wailsapp/wails/v2/internal/messagedispatcher/message"
 	"github.com/wailsapp/wails/v2/internal/servicebus"
@@ -26,6 +27,8 @@ type Client interface {
 	WindowUnminimise()
 	WindowPosition(x int, y int)
 	WindowSize(width int, height int)
+	WindowSetMinSize(width int, height int)
+	WindowSetMaxSize(width int, height int)
 	WindowFullscreen()
 	WindowUnFullscreen()
 	WindowSetColour(colour int)

v2/internal/messagedispatcher/messagedispatcher.go

@@ -2,11 +2,12 @@ package messagedispatcher
 
 import (
 	"encoding/json"
-	"github.com/wailsapp/wails/v2/pkg/options/dialog"
 	"strconv"
 	"strings"
 	"sync"
 
+	"github.com/wailsapp/wails/v2/pkg/options/dialog"
+
 	"github.com/wailsapp/wails/v2/internal/crypto"
 	"github.com/wailsapp/wails/v2/internal/logger"
 	"github.com/wailsapp/wails/v2/internal/messagedispatcher/message"
@@ -349,6 +350,38 @@ func (d *Dispatcher) processWindowMessage(result *servicebus.Message) {
 		for _, client := range d.clients {
 			client.frontend.WindowSize(w, h)
 		}
+	case "minsize":
+		// We need 2 arguments
+		if len(splitTopic) != 4 {
+			d.logger.Error("Invalid number of parameters for 'window:minsize' : %#v", result.Data())
+			return
+		}
+		w, err1 := strconv.Atoi(splitTopic[2])
+		h, err2 := strconv.Atoi(splitTopic[3])
+		if err1 != nil || err2 != nil {
+			d.logger.Error("Invalid integer parameters for 'window:minsize' : %#v", result.Data())
+			return
+		}
+		// Notifh clients
+		for _, client := range d.clients {
+			client.frontend.WindowSetMinSize(w, h)
+		}
+	case "maxsize":
+		// We need 2 arguments
+		if len(splitTopic) != 4 {
+			d.logger.Error("Invalid number of parameters for 'window:maxsize' : %#v", result.Data())
+			return
+		}
+		w, err1 := strconv.Atoi(splitTopic[2])
+		h, err2 := strconv.Atoi(splitTopic[3])
+		if err1 != nil || err2 != nil {
+			d.logger.Error("Invalid integer parameters for 'window:maxsize' : %#v", result.Data())
+			return
+		}
+		// Notifh clients
+		for _, client := range d.clients {
+			client.frontend.WindowSetMaxSize(w, h)
+		}
 	default:
 		d.logger.Error("Unknown window command: %s", command)
 	}

v2/internal/runtime/js/core/desktop.js

@@ -10,6 +10,7 @@ The lightweight framework for web-like apps
 /* jshint esversion: 6 */
 import { SetBindings } from './bindings';
 import { Init } from './main';
+import {RaiseError} from '../desktop/darwin';
 
 // Setup global error handler
 window.onerror = function (msg, url, lineNo, columnNo, error) {
@@ -21,7 +22,7 @@ window.onerror = function (msg, url, lineNo, columnNo, error) {
 		error: JSON.stringify(error),
 		stack: function() { return JSON.stringify(new Error().stack); }(),
 	};
-	window.wails.Log.Error(JSON.stringify(errorMessage));
+	RaiseError(errorMessage);
 };
 
 // Initialise the Runtime

v2/internal/runtime/js/desktop/darwin.js

@@ -25,6 +25,10 @@ export function SendMessage(message) {
     window.webkit.messageHandlers.external.postMessage(message);
 }
 
+export function RaiseError(message) {
+    window.webkit.messageHandlers.error.postMessage(message);
+}
+
 export function Init() {
 
     // Setup drag handler

v2/internal/runtime/js/webpack.desktop.js

@@ -13,7 +13,7 @@ module.exports = {
   mode: 'production',
   output: {
     path: path.resolve(__dirname, '..', 'assets'),
-    filename: 'desktop.js',
+    filename: 'desktop_'+platform+'.js',
     library: 'Wails'
   },
   resolve: {

v2/internal/runtime/scripts/rebuild.go

@@ -3,12 +3,13 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"github.com/wailsapp/wails/v2/internal/fs"
-	"github.com/wailsapp/wails/v2/internal/shell"
 	"io/ioutil"
 	"log"
 	"os"
 	"strings"
+
+	"github.com/wailsapp/wails/v2/internal/fs"
+	"github.com/wailsapp/wails/v2/internal/shell"
 )
 
 func main() {
@@ -49,7 +50,7 @@ func main() {
 			log.Fatal(err)
 		}
 
-		wailsJS := fs.RelativePath("../../../internal/runtime/assets/desktop.js")
+		wailsJS := fs.RelativePath("../../../internal/runtime/assets/desktop_" + platform + ".js")
 		runtimeData, err := ioutil.ReadFile(wailsJS)
 		if err != nil {
 			log.Fatal(err)

v2/internal/runtime/store.go

@@ -6,9 +6,12 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	golog "log"
 	"os"
 	"reflect"
 	"sync"
+
+	"github.com/wailsapp/wails/v2/internal/deepcopy"
 )
 
 // Options defines the optional data that may be used
@@ -64,21 +67,31 @@ func fatal(err error) {
 // New creates a new store
 func (p *StoreProvider) New(name string, defaultValue interface{}) *Store {
 
-	dataType := reflect.TypeOf(defaultValue)
+	if defaultValue == nil {
+		golog.Fatal("Cannot initialise a store with nil")
+	}
 
 	result := Store{
-		name:     name,
+		name:    name,
-		runtime:  p.runtime,
+		runtime: p.runtime,
-		data:     reflect.ValueOf(defaultValue),
-		dataType: dataType,
 	}
 
 	// Setup the sync listener
 	result.setupListener()
 
+	result.Set(defaultValue)
+
 	return &result
 }
 
+func (s *Store) lock() {
+	s.mux.Lock()
+}
+
+func (s *Store) unlock() {
+	s.mux.Unlock()
+}
+
 // OnError takes a function that will be called
 // whenever an error occurs
 func (s *Store) OnError(callback func(error)) {
@@ -105,7 +118,7 @@ func (s *Store) processUpdatedData(data string) error {
 	}
 
 	// Lock mutex for writing
-	s.mux.Lock()
+	s.lock()
 
 	// Handle nulls
 	if newData == nil {
@@ -116,7 +129,7 @@ func (s *Store) processUpdatedData(data string) error {
 	}
 
 	// Unlock mutex
-	s.mux.Unlock()
+	s.unlock()
 
 	return nil
 }
@@ -153,17 +166,27 @@ func (s *Store) setupListener() {
 
 func (s *Store) resync() {
 
-	// Stringify data
+	// Lock
-	newdata, err := json.Marshal(s.data.Interface())
+	s.lock()
-	if err != nil {
+	defer s.unlock()
-		if s.errorHandler != nil {
+
-			s.errorHandler(err)
+	var result string
-			return
+
+	if s.data.IsValid() {
+		rawdata, err := json.Marshal(s.data.Interface())
+		if err != nil {
+			if s.errorHandler != nil {
+				s.errorHandler(err)
+				return
+			}
 		}
+		result = string(rawdata)
+	} else {
+		result = "{}"
 	}
 
 	// Emit event to front end
-	s.runtime.Events.Emit("wails:sync:store:updatedbybackend:"+s.name, string(newdata))
+	s.runtime.Events.Emit("wails:sync:store:updatedbybackend:"+s.name, result)
 
 	// Notify subscribers
 	s.notify()
@@ -176,7 +199,9 @@ func (s *Store) notify() {
 	for _, callback := range s.callbacks {
 
 		// Build args
+		s.lock()
 		args := []reflect.Value{s.data}
+		s.unlock()
 
 		if s.notifySynchronously {
 			callback.Call(args)
@@ -191,16 +216,31 @@ func (s *Store) notify() {
 // and notify listeners of the change
 func (s *Store) Set(data interface{}) error {
 
-	inType := reflect.TypeOf(data)
+	if data == nil {
+		return fmt.Errorf("cannot set store to nil")
+	}
 
-	if inType != s.dataType {
+	s.lock()
-		return fmt.Errorf("invalid data given in Store.Set(). Expected %s, got %s", s.dataType.String(), inType.String())
+
+	dataCopy := deepcopy.Copy(data)
+
+	if dataCopy != nil {
+		inType := reflect.TypeOf(dataCopy)
+
+		if inType != s.dataType && s.data.IsValid() {
+			s.unlock()
+			return fmt.Errorf("invalid data given in Store.Set(). Expected %s, got %s", s.dataType.String(), inType.String())
+		}
+	}
+
+	if s.dataType == nil {
+		s.dataType = reflect.TypeOf(dataCopy)
 	}
 
 	// Save data
-	s.mux.Lock()
+	s.data = reflect.ValueOf(dataCopy)
-	s.data = reflect.ValueOf(data)
+
-	s.mux.Unlock()
+	s.unlock()
 
 	// Resync with subscribers
 	s.resync()
@@ -251,7 +291,9 @@ func (s *Store) Subscribe(callback interface{}) {
 
 	callbackFunc := reflect.ValueOf(callback)
 
+	s.lock()
 	s.callbacks = append(s.callbacks, callbackFunc)
+	s.unlock()
 }
 
 // updaterCheck ensures the given function to Update() is
@@ -301,7 +343,9 @@ func (s *Store) Update(updater interface{}) {
 	}
 
 	// Build args
+	s.lock()
 	args := []reflect.Value{s.data}
+	s.unlock()
 
 	// Make call
 	results := reflect.ValueOf(updater).Call(args)
@@ -312,5 +356,12 @@ func (s *Store) Update(updater interface{}) {
 
 // Get returns the value of the data that's kept in the current state / Store
 func (s *Store) Get() interface{} {
+	s.lock()
+	defer s.unlock()
+
+	if !s.data.IsValid() {
+		return nil
+	}
+
 	return s.data.Interface()
 }

v2/internal/runtime/store_test.go

@@ -0,0 +1,165 @@
+package runtime
+
+import (
+	"context"
+	"math/rand"
+	"sync"
+	"testing"
+	"time"
+
+	internallogger "github.com/wailsapp/wails/v2/internal/logger"
+	"github.com/wailsapp/wails/v2/internal/servicebus"
+	"github.com/wailsapp/wails/v2/pkg/logger"
+
+	is2 "github.com/matryer/is"
+)
+
+func TestStoreProvider_NewWithNilDefault(t *testing.T) {
+	is := is2.New(t)
+
+	defaultLogger := logger.NewDefaultLogger()
+	testLogger := internallogger.New(defaultLogger)
+	//testLogger.SetLogLevel(logger.TRACE)
+	serviceBus := servicebus.New(testLogger)
+	err := serviceBus.Start()
+	is.NoErr(err)
+	defer serviceBus.Stop()
+
+	testRuntime := New(serviceBus)
+	storeProvider := newStore(testRuntime)
+
+	testStore := storeProvider.New("test", 0)
+
+	// You should be able to write a new value into a
+	// store initialised with nil
+	err = testStore.Set(100)
+	is.NoErr(err)
+
+	// You shouldn't be able to write different types to the
+	// store
+	err = testStore.Set(false)
+	is.True(err != nil)
+}
+
+func TestStoreProvider_NewWithScalarDefault(t *testing.T) {
+	is := is2.New(t)
+
+	defaultLogger := logger.NewDefaultLogger()
+	testLogger := internallogger.New(defaultLogger)
+	//testLogger.SetLogLevel(logger.TRACE)
+	serviceBus := servicebus.New(testLogger)
+	err := serviceBus.Start()
+	is.NoErr(err)
+	defer serviceBus.Stop()
+
+	testRuntime := New(serviceBus)
+	storeProvider := newStore(testRuntime)
+	testStore := storeProvider.New("test", 100)
+	value := testStore.Get()
+	is.Equal(value, 100)
+	testStore.resync()
+	value = testStore.Get()
+	is.Equal(value, 100)
+}
+
+func TestStoreProvider_NewWithStructDefault(t *testing.T) {
+	is := is2.New(t)
+
+	defaultLogger := logger.NewDefaultLogger()
+	testLogger := internallogger.New(defaultLogger)
+	//testLogger.SetLogLevel(logger.TRACE)
+	serviceBus := servicebus.New(testLogger)
+	err := serviceBus.Start()
+	is.NoErr(err)
+	defer serviceBus.Stop()
+
+	testRuntime := New(serviceBus)
+	storeProvider := newStore(testRuntime)
+
+	type TestValue struct {
+		Name string
+	}
+	testValue := &TestValue{
+		Name: "hi",
+	}
+
+	testStore := storeProvider.New("test", testValue)
+
+	err = testStore.Set(testValue)
+	is.NoErr(err)
+	testStore.resync()
+	value := testStore.Get()
+	is.Equal(value, testValue)
+	is.Equal(value.(*TestValue).Name, "hi")
+
+	testValue = &TestValue{
+		Name: "there",
+	}
+	err = testStore.Set(testValue)
+	is.NoErr(err)
+	testStore.resync()
+	value = testStore.Get()
+	is.Equal(value, testValue)
+	is.Equal(value.(*TestValue).Name, "there")
+
+}
+
+func TestStoreProvider_RapidReadWrite(t *testing.T) {
+	is := is2.New(t)
+
+	defaultLogger := logger.NewDefaultLogger()
+	testLogger := internallogger.New(defaultLogger)
+	//testLogger.SetLogLevel(logger.TRACE)
+	serviceBus := servicebus.New(testLogger)
+	err := serviceBus.Start()
+	is.NoErr(err)
+	defer serviceBus.Stop()
+
+	testRuntime := New(serviceBus)
+	storeProvider := newStore(testRuntime)
+
+	testStore := storeProvider.New("test", 1)
+
+	ctx, _ := context.WithTimeout(context.Background(), 3*time.Second)
+
+	var wg sync.WaitGroup
+	readers := 100
+	writers := 100
+	wg.Add(readers + writers)
+	// Setup readers
+	go func(testStore *Store, ctx context.Context) {
+		for readerCount := 0; readerCount < readers; readerCount++ {
+			go func(store *Store, ctx context.Context, id int) {
+				for {
+					select {
+					case <-ctx.Done():
+						wg.Done()
+						return
+					default:
+						store.Get()
+					}
+				}
+			}(testStore, ctx, readerCount)
+		}
+	}(testStore, ctx)
+
+	// Setup writers
+	go func(testStore *Store, ctx context.Context) {
+		for writerCount := 0; writerCount < writers; writerCount++ {
+			go func(store *Store, ctx context.Context, id int) {
+				for {
+					select {
+					case <-ctx.Done():
+						wg.Done()
+						return
+					default:
+						err := store.Set(rand.Int())
+						is.NoErr(err)
+					}
+				}
+			}(testStore, ctx, writerCount)
+		}
+	}(testStore, ctx)
+
+	wg.Wait()
+}

v2/internal/runtime/window.go

@@ -18,6 +18,8 @@ type Window interface {
 	Unminimise()
 	SetTitle(title string)
 	SetSize(width int, height int)
+	SetMinSize(width int, height int)
+	SetMaxSize(width int, height int)
 	SetPosition(x int, y int)
 	Fullscreen()
 	UnFullscreen()
@@ -85,6 +87,18 @@ func (w *window) SetSize(width int, height int) {
 	w.bus.Publish(message, "")
 }
 
+// SetSize sets the size of the window
+func (w *window) SetMinSize(width int, height int) {
+	message := fmt.Sprintf("window:minsize:%d:%d", width, height)
+	w.bus.Publish(message, "")
+}
+
+// SetSize sets the size of the window
+func (w *window) SetMaxSize(width int, height int) {
+	message := fmt.Sprintf("window:maxsize:%d:%d", width, height)
+	w.bus.Publish(message, "")
+}
+
 // SetPosition sets the position of the window
 func (w *window) SetPosition(x int, y int) {
 	message := fmt.Sprintf("window:position:%d:%d", x, y)

v2/internal/servicebus/servicebus.go

@@ -71,10 +71,11 @@ func (s *ServiceBus) Start() error {
 	}
 
 	// We run in a different thread
+	s.wg.Add(1)
+
 	go func() {
 
 		quit := false
-		s.wg.Add(1)
 
 		// Loop until we get a quit message
 		for !quit {