Add Exported() []string to plugin API

v3/examples/plugins/plugins/hashes/plugin.go

@@ -26,6 +26,12 @@ func (r *Plugin) Init(_ *application.App) error {
 	return nil
 }
 
+func (r *Plugin) Exported() []string {
+	return []string{
+		"Generate",
+	}
+}
+
 // ---------------- Plugin Methods ----------------
 
 type Hashes struct {

v3/examples/plugins/store.json

@@ -1 +1 @@
-{"url":null,"url2":"https://reddit.com"}
+{"url2":"https://reddit.com"}

v3/pkg/application/bindings.go

@@ -24,6 +24,7 @@ var reservedPluginMethods = []string{
 	"Name",
 	"Init",
 	"Shutdown",
+	"Exported",
 }
 
 // Parameter defines a Go method parameter
@@ -113,10 +114,17 @@ func (b *Bindings) AddPlugins(plugins map[string]Plugin) error {
 			return fmt.Errorf("cannot add plugin '%s' to app: %s", pluginID, err.Error())
 		}
 
+		exportedMethods := plugin.Exported()
+
 		for _, method := range methods {
+			// Do not expose reserved methods
 			if lo.Contains(reservedPluginMethods, method.Name) {
 				continue
 			}
+			// Do not expose methods that are not in the exported list
+			if !lo.Contains(exportedMethods, method.Name) {
+				continue
+			}
 			packageName := "wails-plugins"
 			structName := pluginID
 			methodName := method.Name

v3/pkg/application/plugins.go

@@ -4,6 +4,8 @@ type Plugin interface {
 	Name() string
 	Init(app *App) error
 	Shutdown()
+	// Exported is a list of method names that should be exposed to the frontend
+	Exported() []string
 }
 
 type PluginManager struct {

v3/plugins/README.md

@@ -0,0 +1,29 @@
+# Plugins
+
+Plugins are a way to extend the functionality of your Wails application.
+
+## Creating a plugin
+
+Plugins are standard Go structure that adhere to the following interface:
+
+```go
+type Plugin interface {
+    Name() string
+    Init(*application.App) error
+    Shutdown() 
+    Exported() []string
+}
+```
+
+The `Name()` method returns the name of the plugin. This is used for logging purposes.
+
+The `Init(*application.App) error` method is called when the plugin is loaded. The `*application.App` 
+parameter is the application that the plugin is being loaded into. Any errors will prevent
+the application from starting.
+
+The `Shutdown()` method is called when the application is shutting down. 
+
+The `Exported()` method returns a list of exported functions that can be called from 
+the frontend. These method names must exactly match the names of the methods exported 
+by the plugin.
+

v3/plugins/browser/plugin.go

@@ -26,6 +26,13 @@ func (p *Plugin) Init(_ *application.App) error {
 	return nil
 }
 
+func (p *Plugin) Exported() []string {
+	return []string{
+		"OpenURL",
+		"OpenFile",
+	}
+}
+
 // ---------------- Plugin Methods ----------------
 
 func (p *Plugin) OpenURL(url string) error {

v3/plugins/kvstore/kvstore.go

@@ -3,6 +3,7 @@ package kvstore
 import (
 	"encoding/json"
 	"github.com/wailsapp/wails/v3/pkg/application"
+	"github.com/wailsapp/wails/v3/pkg/logger"
 	"io"
 	"os"
 	"sync"
@@ -14,6 +15,7 @@ type KeyValueStore struct {
 	data     map[string]any
 	unsaved  bool
 	lock     sync.RWMutex
+	app      *application.App
 }
 
 type Config struct {
@@ -47,7 +49,8 @@ func (kvs *KeyValueStore) Name() string {
 
 // Init is called when the plugin is loaded. It is passed the application.App
 // instance. This is where you should do any setup.
-func (kvs *KeyValueStore) Init(_ *application.App) error {
+func (kvs *KeyValueStore) Init(app *application.App) error {
+	kvs.app = app
 	err := kvs.open(kvs.config.Filename)
 	if err != nil {
 		return err
@@ -56,9 +59,17 @@ func (kvs *KeyValueStore) Init(_ *application.App) error {
 	return nil
 }
 
+func (kvs *KeyValueStore) Exported() []string {
+	return []string{
+		"Set",
+		"Get",
+		"Save",
+	}
+}
+
 // ---------------- Plugin Methods ----------------
 
-func (kvs *KeyValueStore) open(filename string) error {
+func (kvs *KeyValueStore) open(filename string) (err error) {
 	kvs.filename = filename
 	kvs.data = make(map[string]any)
 
@@ -69,7 +80,19 @@ func (kvs *KeyValueStore) open(filename string) error {
 		}
 		return err
 	}
-	defer file.Close()
+	defer func() {
+		err2 := file.Close()
+		if err2 != nil {
+			if err == nil {
+				err = err2
+			} else {
+				kvs.app.Log(&logger.Message{
+					Level:   "error",
+					Message: err.Error(),
+				})
+			}
+		}
+	}()
 
 	bytes, err := io.ReadAll(file)
 	if err != nil {
@@ -120,7 +143,11 @@ func (kvs *KeyValueStore) Get(key string) any {
 // Set sets the value for the given key. If AutoSave is true, the store is saved to disk.
 func (kvs *KeyValueStore) Set(key string, value any) error {
 	kvs.lock.Lock()
-	kvs.data[key] = value
+	if value == nil {
+		delete(kvs.data, key)
+	} else {
+		kvs.data[key] = value
+	}
 	kvs.lock.Unlock()
 	if kvs.config.AutoSave {
 		err := kvs.Save()