tebeka · rmescandon · Jun 14, 2022
diff --git a/internal/seleniumtest/seleniumtest.go b/internal/seleniumtest/seleniumtest.go
@@ -138,6 +138,7 @@ func RunCommonTests(t *testing.T, c Config) {
 	t.Run("PageSource", runTest(testPageSource, c))
 	t.Run("FindElement", runTest(testFindElement, c))
 	t.Run("FindElements", runTest(testFindElements, c))
+	t.Run("TestShadowDOM", runTest(testShadowDOM, c))
 	t.Run("SendKeys", runTest(testSendKeys, c))
 	t.Run("Click", runTest(testClick, c))
 	t.Run("GetCookies", runTest(testGetCookies, c))
@@ -567,6 +568,43 @@ func testFindElements(t *testing.T, c Config) {
 	evaluateElement(t, wd, elems[0])
 }
 
+func testShadowDOM(t *testing.T, c Config) {
+	wd := newRemote(t, newTestCapabilities(t, c), c)
+	defer quitRemote(t, wd)
+
+	if err := wd.Get(c.ServerURL + "/shadow"); err != nil {
+		t.Fatalf("wd.Get(%q) returned error: %v", c.ServerURL, err)
+	}
+
+	we, err := wd.FindElement(selenium.ByID, "host-element")
+	if err != nil {
+		t.Fatalf("wd.FindElement('id', 'host-element') failed to obtain the host element of the shadow DOM: %s", err)
+	}
+
+	sr, err := we.GetElementShadowRoot()
+	if err != nil {
+		t.Fatalf("we.GetElementShadowRoot() failed to obtain the shadow root element: %s", err)
+	}
+
+	swe, err := sr.FindElement(selenium.ByCSSSelector, "button[id='shadow-button']")
+	if err != nil {
+		t.Fatalf("sr.FindElement('css selector', 'button['id=\\'shadow-button\\']) failed to obtain the shadow DOM element: %s", err)
+	}
+
+	if swe == nil {
+		t.Fatalf("obtained element from shadow DOM is null")
+	}
+
+	swes, err := sr.FindElements(selenium.ByCSSSelector, "button")
+	if err != nil {
+		t.Fatalf("sr.FindElements('css selector', 'button) failed to obtain the shadow DOM elements: %s", err)
+	}
+
+	if swes == nil || len(swes) != 2 {
+		t.Fatalf("could not obtained all elements from shadow DOM")
+	}
+}
+
 func testSendKeys(t *testing.T, c Config) {
 	wd := newRemote(t, newTestCapabilities(t, c), c)
 	defer quitRemote(t, wd)
@@ -1604,6 +1642,24 @@ var alertPage = `
 </html>
 `
 
+var shadowDOMPage = `
+<html>
+<head>
+	<title>Go Selenium Test Suite - Shadow DOM Page</title>
+</head>
+<body>
+	This page contains a Shadow DOM.
+
+	<div id="host-element">
+		<template shadowroot="open">
+			<button id="shadow-button"/>
+			<button id="another-shadow-button"/>
+		</template>
+	</div>
+</body>
+</html>
+`
+
 var Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	path := r.URL.Path
 	page, ok := map[string]string{
@@ -1614,6 +1670,7 @@ var Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		"/frame":  framePage,
 		"/title":  titleChangePage,
 		"/alert":  alertPage,
+		"/shadow": shadowDOMPage,
 	}[path]
 	if !ok {
 		http.NotFound(w, r)

diff --git a/remote.go b/remote.go
@@ -314,6 +314,15 @@ func (wd *remoteWD) boolCommand(urlTemplate string) (bool, error) {
 	return reply.Value, nil
 }
 
+func (wd *remoteWD) shadowRootCommand(urlTemplate string) (ShadowRoot, error) {
+	url := wd.requestURL(urlTemplate, wd.id)
+	response, err := wd.execute("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	return wd.DecodeShadowRoot(response)
+}
+
 func (wd *remoteWD) Status() (*Status, error) {
 	url := wd.requestURL("/status")
 	reply, err := wd.execute("GET", url, nil)
@@ -689,6 +698,39 @@ func (wd *remoteWD) find(by, value, suffix, url string) ([]byte, error) {
 	return wd.execute("POST", wd.requestURL(url+suffix, wd.id), data)
 }
 
+func (wd *remoteWD) DecodeShadowRoot(data []byte) (ShadowRoot, error) {
+	reply := new(struct{ Value map[string]string })
+	if err := json.Unmarshal(data, &reply); err != nil {
+		return nil, err
+	}
+
+	id := shadowRootIDFromValue(reply.Value)
+	if id == "" {
+		return nil, fmt.Errorf("invalid shadow root returned: %+v", reply)
+	}
+	return &remoteSR{
+		parent: wd,
+		id:     id,
+	}, nil
+}
+
+const (
+	// shadowIdentifier is the string constant defined by the W3C
+	// specification that is the key for the map that contains a unique shadow root identifier.
+	shadowRootIdentifier = "shadow-6066-11e4-a52e-4f735466cecf"
+)
+
+func shadowRootIDFromValue(v map[string]string) string {
+	for _, key := range []string{shadowRootIdentifier} {
+		v, ok := v[key]
+		if !ok || v == "" {
+			continue
+		}
+		return v
+	}
+	return ""
+}
+
 func (wd *remoteWD) DecodeElement(data []byte) (WebElement, error) {
 	reply := new(struct{ Value map[string]string })
 	if err := json.Unmarshal(data, &reply); err != nil {
@@ -1440,6 +1482,11 @@ func (elem *remoteWE) FindElements(by, value string) ([]WebElement, error) {
 	return elem.parent.DecodeElements(response)
 }
 
+func (elem *remoteWE) GetElementShadowRoot() (ShadowRoot, error) {
+	url := fmt.Sprintf("/session/%%s/element/%s/shadow", elem.id)
+	return elem.parent.shadowRootCommand(url)
+}
+
 func (elem *remoteWE) boolQuery(urlTemplate string) (bool, error) {
 	return elem.parent.boolCommand(fmt.Sprintf(urlTemplate, elem.id))
 }
@@ -1579,3 +1626,28 @@ func (elem *remoteWE) Screenshot(scroll bool) ([]byte, error) {
 	decoder := base64.NewDecoder(base64.StdEncoding, bytes.NewBuffer(buf))
 	return ioutil.ReadAll(decoder)
 }
+
+type remoteSR struct {
+	parent *remoteWD
+	id     string
+}
+
+func (elem *remoteSR) FindElement(by, value string) (WebElement, error) {
+	url := fmt.Sprintf("/session/%%s/shadow/%s/element", elem.id)
+	response, err := elem.parent.find(by, value, "", url)
+	if err != nil {
+		return nil, err
+	}
+
+	return elem.parent.DecodeElement(response)
+}
+
+func (elem *remoteSR) FindElements(by, value string) ([]WebElement, error) {
+	url := fmt.Sprintf("/session/%%s/shadow/%s/element", elem.id)
+	response, err := elem.parent.find(by, value, "s", url)
+	if err != nil {
+		return nil, err
+	}
+
+	return elem.parent.DecodeElements(response)
+}
diff --git a/selenium.go b/selenium.go
@@ -450,6 +450,8 @@ type WebElement interface {
 	FindElement(by, value string) (WebElement, error)
 	// FindElement finds multiple children elements.
 	FindElements(by, value string) ([]WebElement, error)
+	// Gets the shadow root element of a shadow DOM whose host is this element
+	GetElementShadowRoot() (ShadowRoot, error)
 
 	// TagName returns the element's name.
 	TagName() (string, error)
@@ -479,3 +481,11 @@ type WebElement interface {
 	// Screenshot takes a screenshot of the attribute scroll'ing if necessary.
 	Screenshot(scroll bool) ([]byte, error)
 }
+
+// ShadowRoot defines methods supported by a shadow DOM root element
+type ShadowRoot interface {
+	// FindElement finds a child element into the shadow DOM
+	FindElement(by, value string) (WebElement, error)
+	// FindElement finds multiple children elements into the shadow DOM
+	FindElements(by, value string) ([]WebElement, error)
+}