feat(extension): expose host version and WebView page events

pkg/download/engine/engine.go

@@ -276,3 +276,8 @@ func callExportedFunction(fn func(goja.FunctionCall) goja.Value, args ...goja.Va
 		Arguments: args,
 	}), nil
 }
+
+// Post queues a notification without waiting for its callback or returned promise.
+func (e *Engine) Post(fn func(*goja.Runtime)) bool {
+	return e.loop.RunOnLoop(fn)
+}

pkg/download/engine/webview/events.go

@@ -0,0 +1,93 @@
+package webview
+
+import (
+	"fmt"
+	"sync"
+)
+
+// Event is a main-page notification. Data follows WebviewEventMap.
+type Event struct {
+	Name string         `json:"event"`
+	Data map[string]any `json:"data"`
+}
+
+type EventSource interface {
+	On(event string, handler func(Event)) (unsubscribe func(), err error)
+}
+
+func ValidEvent(event string) bool {
+	switch event {
+	case "url-changed", "load", "load-error", "closed":
+		return true
+	}
+	return false
+}
+
+// EventHub delivers notifications in registration order. Handlers must only
+// enqueue work, never block or enter the browser. Closed is terminal.
+type EventHub struct {
+	mu        sync.Mutex
+	seq       uint64
+	listeners []eventListener
+	closed    bool
+}
+type eventListener struct {
+	id      uint64
+	name    string
+	handler func(Event)
+}
+
+func (h *EventHub) On(name string, handler func(Event)) (func(), error) {
+	if !ValidEvent(name) || handler == nil {
+		return nil, fmt.Errorf("invalid webview event or handler: %s", name)
+	}
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	if h.closed {
+		return nil, fmt.Errorf("webview page is closed")
+	}
+	h.seq++
+	id := h.seq
+	h.listeners = append(h.listeners, eventListener{id, name, handler})
+	return func() {
+		h.mu.Lock()
+		defer h.mu.Unlock()
+		for i, listener := range h.listeners {
+			if listener.id == id {
+				h.listeners = append(h.listeners[:i], h.listeners[i+1:]...)
+				break
+			}
+		}
+	}, nil
+}
+
+func (h *EventHub) Emit(event Event) {
+	h.mu.Lock()
+	if h.closed {
+		h.mu.Unlock()
+		return
+	}
+	listeners := append([]eventListener(nil), h.listeners...)
+	if event.Name == "closed" {
+		h.closed = true
+		h.listeners = nil
+	}
+	h.mu.Unlock()
+	for _, listener := range listeners {
+		if listener.name == event.Name {
+			listener.handler(event)
+		}
+	}
+}
+
+func (p *PageHandle) On(name string, handler func(Event)) (func(), error) {
+	page, err := p.page()
+	if err != nil {
+		return nil, err
+	}
+	source, ok := page.(EventSource)
+	if !ok {
+		return nil, fmt.Errorf("WebView provider does not support events")
+	}
+	return source.On(name, handler)
+}

pkg/download/engine/webview/events_test.go

@@ -0,0 +1,52 @@
+package webview
+
+import (
+	"reflect"
+	"sync"
+	"testing"
+)
+
+func TestEventHubLifecycle(t *testing.T) {
+	var hub EventHub
+	var got []string
+	hub.Emit(Event{Name: "load"}) // Never replay pre-registration events.
+	off, err := hub.On("load", func(Event) { got = append(got, "first") })
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, _ = hub.On("load", func(Event) { got = append(got, "second") })
+	_, _ = hub.On("closed", func(e Event) {
+		got = append(got, e.Data["reason"].(string))
+		off() // Unsubscription from a callback must not deadlock.
+	})
+	hub.Emit(Event{Name: "load"})
+	off()
+	off()
+	hub.Emit(Event{Name: "load"})
+	hub.Emit(Event{Name: "closed", Data: map[string]any{"reason": "api"}})
+	hub.Emit(Event{Name: "load"})
+	hub.Emit(Event{Name: "closed"})
+	if !reflect.DeepEqual(got, []string{"first", "second", "second", "api"}) {
+		t.Fatal(got)
+	}
+	if len(hub.listeners) != 0 {
+		t.Fatal("closed page retained listeners")
+	}
+	if _, err := hub.On("load", func(Event) {}); err == nil {
+		t.Fatal("registration on closed page succeeded")
+	}
+}
+
+func TestEventHubConcurrentUnsubscribe(t *testing.T) {
+	var hub EventHub
+	off, _ := hub.On("load", func(Event) {})
+	var wg sync.WaitGroup
+	for i := 0; i < 20; i++ {
+		wg.Add(1)
+		go func() { defer wg.Done(); off(); hub.Emit(Event{Name: "load"}) }()
+	}
+	wg.Wait()
+	if _, err := hub.On("invalid", func(Event) {}); err == nil {
+		t.Fatal("accepted invalid event")
+	}
+}

pkg/download/engine/webview/rpc.go

@@ -8,6 +8,7 @@ const (
 	MethodProfileRemove     = "profile.remove"
 	MethodIsAvailable       = "webview.isAvailable"
 	MethodPageOpen          = "page.open"
+	MethodPageEvents        = "page.events"
 	MethodPageAddInitScript = "page.addInitScript"
 	MethodPageGoto          = "page.goto"
 	MethodPageExecute       = "page.execute"

pkg/download/extension.go

@@ -376,7 +376,7 @@ func doTrigger[T any](d *Downloader, event ActivationEvent, req *base.Request, c
 					gopeed.Runtime = &InstanceRuntime{
 						WebView: d.newExtensionWebViewRuntime(session, ext.buildIdentity()),
 					}
-					err = injectGopeed(engine.Runtime, gopeed)
+					err = injectGopeed(engine.Runtime, gopeed, engine.Post)
 					if err != nil {
 						gopeed.Logger.logger.Error().Err(err).Msgf("[%s] engine inject failed", ext.buildIdentity())
 						return
@@ -651,20 +651,22 @@ func (h InstanceEvents) OnDone(fn engine.JSFunction) {
 }
 
 type ExtensionInfo struct {
-	Identity string `json:"identity"`
-	Name     string `json:"name"`
-	Author   string `json:"author"`
-	Title    string `json:"title"`
-	Version  string `json:"version"`
+	HostVersion string `json:"hostVersion"`
+	Identity    string `json:"identity"`
+	Name        string `json:"name"`
+	Author      string `json:"author"`
+	Title       string `json:"title"`
+	Version     string `json:"version"`
 }
 
 func NewExtensionInfo(ext *Extension) *ExtensionInfo {
 	return &ExtensionInfo{
-		Identity: ext.buildIdentity(),
-		Name:     ext.Name,
-		Author:   ext.Author,
-		Title:    ext.Title,
-		Version:  ext.Version,
+		HostVersion: base.Version,
+		Identity:    ext.buildIdentity(),
+		Name:        ext.Name,
+		Author:      ext.Author,
+		Title:       ext.Title,
+		Version:     ext.Version,
 	}
 }
 

pkg/download/extension_engine.go

@@ -33,7 +33,7 @@ func (d *Downloader) NewExtensionEngine(ext *Extension, settings map[string]any)
 			WebView: d.newExtensionWebViewRuntime(session, ext.buildIdentity()),
 		},
 	}
-	if err := injectGopeed(engine.Runtime, gopeed); err != nil {
+	if err := injectGopeed(engine.Runtime, gopeed, engine.Post); err != nil {
 		session.CloseIfIdle()
 		return nil, err
 	}

pkg/download/extension_runtime_events_test.go

@@ -0,0 +1,117 @@
+package download
+
+import (
+	"fmt"
+	"github.com/GopeedLab/gopeed/pkg/base"
+	"github.com/GopeedLab/gopeed/pkg/download/engine"
+	wv "github.com/GopeedLab/gopeed/pkg/download/engine/webview"
+	"testing"
+	"time"
+)
+
+type eventTestPage struct {
+	fakeRuntimeWebViewPage
+	wv.EventHub
+}
+
+func (p *eventTestPage) Close() error {
+	p.Emit(wv.Event{Name: "closed", Data: map[string]any{"reason": "api"}})
+	return nil
+}
+
+type eventTestOpener struct{ page wv.Page }
+
+func (o eventTestOpener) Open(wv.OpenOptions) (wv.Page, error) { return o.page, nil }
+
+func TestExtensionInfoHostVersion(t *testing.T) {
+	e := engine.NewEngine(nil)
+	defer e.Close()
+	info := NewExtensionInfo(&Extension{Name: "sample", Author: "test", Version: "1.2.3"})
+	if err := injectGopeed(e.Runtime, &Instance{Info: info}, e.Post); err != nil {
+		t.Fatal(err)
+	}
+	result, err := e.RunString(`gopeed.info.hostVersion + "/" + gopeed.info.version`)
+	if err != nil || result != base.Version+"/1.2.3" {
+		t.Fatalf("%v %v", result, err)
+	}
+}
+
+func TestExtensionWebViewEvents(t *testing.T) {
+	e := engine.NewEngine(nil)
+	defer e.Close()
+	page := &eventTestPage{}
+	runtime := wv.NewRuntime(eventTestOpener{page}, true)
+	defer runtime.Close()
+	if err := injectGopeed(e.Runtime, &Instance{Runtime: &InstanceRuntime{WebView: runtime}}, e.Post); err != nil {
+		t.Fatal(err)
+	}
+	_, err := e.RunString(`var page = gopeed.runtime.webview.open(); var seen = []; var off;
+ (async () => {
+  const registered = page.on("load", () => { seen.push("load"); return new Promise(() => {}); });
+  if (!(registered instanceof Promise)) throw new Error("on must return a Promise");
+  off = await registered;
+  await page.on("closed", data => seen.push(data.reason));
+  for (const args of [["invalid", () => {}], ["load", 1]]) {
+   let rejected = false;
+   try { await page.on(...args); } catch (_) { rejected = true; }
+   if (!rejected) throw new Error("invalid listener accepted");
+  }
+ })()`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	page.Emit(wv.Event{Name: "load", Data: map[string]any{"url": "https://example.test"}})
+	result, err := e.RunString(`off(); off(); seen.join(",")`)
+	if err != nil || result != "load" {
+		t.Fatalf("%v %v", result, err)
+	}
+	page.Emit(wv.Event{Name: "load"})
+	if _, err = e.RunString(`page.close()`); err != nil {
+		t.Fatal(err)
+	}
+	result, err = e.RunString(`seen.join(",")`)
+	if err != nil || result != "load,api" {
+		t.Fatalf("%v %v", result, err)
+	}
+}
+
+// Navigation must not occupy the Goja loop: a notification can execute page
+// operations even while the original goto promise is still pending.
+type navigationEventTestPage struct {
+	eventTestPage
+	release chan struct{}
+}
+
+func (p *navigationEventTestPage) Goto(url string, _ wv.GotoOptions) error {
+	p.Emit(wv.Event{Name: "load", Data: map[string]any{"url": url}})
+	select {
+	case <-p.release:
+		return nil
+	case <-time.After(2 * time.Second):
+		return fmt.Errorf("event callback blocked by navigation")
+	}
+}
+func (p *navigationEventTestPage) Execute(string, ...any) (any, error) {
+	close(p.release)
+	return nil, nil
+}
+func TestExtensionWebViewEventsDuringNavigation(t *testing.T) {
+	e := engine.NewEngine(nil)
+	defer e.Close()
+	page := &navigationEventTestPage{release: make(chan struct{})}
+	runtime := wv.NewRuntime(eventTestOpener{page}, true)
+	defer runtime.Close()
+	if err := injectGopeed(e.Runtime, &Instance{Runtime: &InstanceRuntime{WebView: runtime}}, e.Post); err != nil {
+		t.Fatal(err)
+	}
+	result, err := e.RunString(`(async () => {
+  const page = await gopeed.runtime.webview.open();
+  await page.on("load", () => page.execute("release"));
+  if (await page.addInitScript("globalThis.ready = true") !== undefined) throw new Error("init result must be void");
+  if (await page.goto("https://example.test") !== undefined) throw new Error("goto result must be void");
+  return true;
+ })()`)
+	if err != nil || result != true {
+		t.Fatalf("%v %v", result, err)
+	}
+}

pkg/download/extension_runtime_webview.go

@@ -8,7 +8,7 @@ import (
 	"github.com/dop251/goja"
 )
 
-func injectGopeed(vm *goja.Runtime, gopeed *Instance) error {
+func injectGopeed(vm *goja.Runtime, gopeed *Instance, post func(func(*goja.Runtime)) bool) error {
 	gopeedObject := vm.NewObject()
 	if gopeed == nil {
 		return vm.Set("gopeed", gopeedObject)
@@ -37,7 +37,7 @@ func injectGopeed(vm *goja.Runtime, gopeed *Instance) error {
 			return err
 		}
 		if gopeed.Runtime.WebView != nil {
-			if err := runtimeObject.Set("webview", newJSWebViewRuntime(vm, gopeed.Runtime.WebView)); err != nil {
+			if err := runtimeObject.Set("webview", newJSWebViewRuntime(vm, gopeed.Runtime.WebView, post)); err != nil {
 				return err
 			}
 		}
@@ -103,7 +103,7 @@ func newJSEventsRuntime(vm *goja.Runtime, events InstanceEvents) *goja.Object {
 	return obj
 }
 
-func newJSWebViewRuntime(vm *goja.Runtime, runtime *enginewebview.Runtime) *goja.Object {
+func newJSWebViewRuntime(vm *goja.Runtime, runtime *enginewebview.Runtime, post func(func(*goja.Runtime)) bool) *goja.Object {
 	obj := vm.NewObject()
 	_ = obj.Set("isAvailable", func(goja.FunctionCall) goja.Value {
 		return vm.ToValue(runtime.IsAvailable())
@@ -113,35 +113,48 @@ func newJSWebViewRuntime(vm *goja.Runtime, runtime *enginewebview.Runtime) *goja
 		if err != nil {
 			panic(vm.ToValue(err))
 		}
-		return newJSWebViewPage(vm, page)
+		return newJSWebViewPage(vm, page, post)
 	})
 	return obj
 }
 
-func newJSWebViewPage(vm *goja.Runtime, page *enginewebview.PageHandle) *goja.Object {
+func newJSWebViewPage(vm *goja.Runtime, page *enginewebview.PageHandle, post func(func(*goja.Runtime)) bool) *goja.Object {
 	obj := vm.NewObject()
+	_ = obj.Set("on", func(call goja.FunctionCall) goja.Value {
+		promise, resolve, reject := vm.NewPromise()
+		handler, ok := goja.AssertFunction(call.Argument(1))
+		if !ok {
+			_ = reject(vm.NewTypeError("handler must be a function"))
+			return vm.ToValue(promise)
+		}
+		unsubscribe, err := page.On(call.Argument(0).String(), func(event enginewebview.Event) {
+			post(func(vm *goja.Runtime) {
+				// A callback is a notification: never await its returned promise.
+				_, _ = handler(goja.Undefined(), vm.ToValue(event.Data))
+			})
+		})
+		if err != nil {
+			_ = reject(vm.NewGoError(err))
+		} else {
+			_ = resolve(func(goja.FunctionCall) goja.Value { unsubscribe(); return goja.Undefined() })
+		}
+		return vm.ToValue(promise)
+	})
+
 	_ = obj.Set("addInitScript", func(call goja.FunctionCall) goja.Value {
 		script, err := requireStringArg(call, 0, "script")
 		if err != nil {
 			panic(vm.ToValue(err))
 		}
-		if err := page.AddInitScript(script); err != nil {
-			panic(vm.ToValue(err))
-		}
-		return goja.Undefined()
+		return webviewPromise(vm, post, func() (any, error) { return nil, page.AddInitScript(script) })
 	})
 	_ = obj.Set("goto", func(call goja.FunctionCall) goja.Value {
 		url, err := requireStringArg(call, 0, "url")
 		if err != nil {
 			panic(vm.ToValue(err))
 		}
-		if err := page.Goto(
-			url,
-			optionalMap(call.Argument(1)),
-		); err != nil {
-			panic(vm.ToValue(err))
-		}
-		return goja.Undefined()
+		opts := optionalMap(call.Argument(1))
+		return webviewPromise(vm, post, func() (any, error) { return nil, page.Goto(url, opts) })
 	})
 	_ = obj.Set("execute", func(call goja.FunctionCall) goja.Value {
 		expression, err := enginewebview.NormalizeExecutableValue(call.Argument(0))
@@ -254,10 +267,7 @@ func newJSWebViewPage(vm *goja.Runtime, page *enginewebview.PageHandle) *goja.Ob
 		return vm.ToValue(result)
 	})
 	_ = obj.Set("close", func(goja.FunctionCall) goja.Value {
-		if err := page.Close(); err != nil {
-			panic(vm.ToValue(err))
-		}
-		return goja.Undefined()
+		return webviewPromise(vm, post, func() (any, error) { return nil, page.Close() })
 	})
 	return obj
 }
@@ -290,3 +300,22 @@ func requireStringArg(call goja.FunctionCall, index int, name string) (string, e
 	}
 	return value.String(), nil
 }
+
+// Browser operations run outside Goja, allowing notifications to be delivered
+// while navigation is pending. Only the event loop touches JavaScript values.
+func webviewPromise(vm *goja.Runtime, post func(func(*goja.Runtime)) bool, work func() (any, error)) goja.Value {
+	promise, resolve, reject := vm.NewPromise()
+	go func() {
+		value, err := work()
+		post(func(vm *goja.Runtime) {
+			if err != nil {
+				_ = reject(vm.NewGoError(err))
+			} else if value == nil {
+				_ = resolve(goja.Undefined())
+			} else {
+				_ = resolve(value)
+			}
+		})
+	}()
+	return vm.ToValue(promise)
+}

pkg/download/extension_webview_config.go

@@ -181,3 +181,11 @@ func (d *Downloader) removeExtensionWebViewProfile(identity string) error {
 	}
 	return os.RemoveAll(path)
 }
+
+func (p *extensionWebViewPage) On(event string, handler func(enginewebview.Event)) (func(), error) {
+	source, ok := p.Page.(enginewebview.EventSource)
+	if !ok {
+		return nil, fmt.Errorf("WebView provider does not support events")
+	}
+	return source.On(event, handler)
+}