LibWeb+WebContent+WebDriver: Implement Find Element From Shadow Root

Userland/Libraries/LibWeb/WebDriver/Client.cpp

@@ -73,6 +73,7 @@ static constexpr auto s_webdriver_endpoints = Array {
     ROUTE(POST, "/session/:session_id/elements"sv, find_elements),
     ROUTE(POST, "/session/:session_id/element/:element_id/element"sv, find_element_from_element),
     ROUTE(POST, "/session/:session_id/element/:element_id/elements"sv, find_elements_from_element),
+    ROUTE(POST, "/session/:session_id/shadow/:shadow_id/element"sv, find_element_from_shadow_root),
     ROUTE(GET, "/session/:session_id/element/active"sv, get_active_element),
     ROUTE(GET, "/session/:session_id/element/:element_id/shadow"sv, get_element_shadow_root),
     ROUTE(GET, "/session/:session_id/element/:element_id/selected"sv, is_element_selected),

Userland/Libraries/LibWeb/WebDriver/Client.h

@@ -61,6 +61,7 @@ public:
     virtual Response find_elements(Parameters parameters, JsonValue payload) = 0;
     virtual Response find_element_from_element(Parameters parameters, JsonValue payload) = 0;
     virtual Response find_elements_from_element(Parameters parameters, JsonValue payload) = 0;
+    virtual Response find_element_from_shadow_root(Parameters parameters, JsonValue payload) = 0;
     virtual Response get_active_element(Parameters parameters, JsonValue payload) = 0;
     virtual Response get_element_shadow_root(Parameters parameters, JsonValue payload) = 0;
     virtual Response is_element_selected(Parameters parameters, JsonValue payload) = 0;

Userland/Services/WebContent/WebDriverClient.ipc

@@ -23,6 +23,7 @@ endpoint WebDriverClient {
     find_elements(JsonValue payload) => (Web::WebDriver::Response response)
     find_element_from_element(JsonValue payload, String element_id) => (Web::WebDriver::Response response)
     find_elements_from_element(JsonValue payload, String element_id) => (Web::WebDriver::Response response)
+    find_element_from_shadow_root(JsonValue payload, String shadow_id) => (Web::WebDriver::Response response)
     get_active_element() => (Web::WebDriver::Response response)
     get_element_shadow_root(String element_id) => (Web::WebDriver::Response response)
     is_element_selected(String element_id) => (Web::WebDriver::Response response)

Userland/Services/WebContent/WebDriverConnection.cpp

@@ -181,6 +181,23 @@ static JsonObject shadow_root_reference_object(Web::DOM::ShadowRoot const& shado
     return object;
 }
 
+// https://w3c.github.io/webdriver/#dfn-get-a-known-shadow-root
+static ErrorOr<Web::DOM::ShadowRoot*, Web::WebDriver::Error> get_known_shadow_root(StringView shadow_id)
+{
+    // NOTE: The whole concept of "known shadow roots" is not implemented yet. See get_or_create_a_shadow_root_reference().
+    //       For now the shadow root is only represented by its ID.
+    auto shadow_root = shadow_id.to_int();
+    if (!shadow_root.has_value())
+        return Web::WebDriver::Error::from_code(Web::WebDriver::ErrorCode::InvalidArgument, "Shadow ID is not an integer");
+
+    auto* node = Web::DOM::Node::from_id(*shadow_root);
+
+    if (!node || !node->is_shadow_root())
+        return Web::WebDriver::Error::from_code(Web::WebDriver::ErrorCode::NoSuchElement, String::formatted("Could not find shadow root with ID: {}", shadow_id));
+
+    return static_cast<Web::DOM::ShadowRoot*>(node);
+}
+
 // https://w3c.github.io/webdriver/#dfn-scrolls-into-view
 static void scroll_element_into_view(Web::DOM::Element& element)
 {
@@ -736,6 +753,39 @@ Messages::WebDriverClient::FindElementsFromElementResponse WebDriverConnection::
     return TRY(find(*start_node, *location_strategy, selector));
 }
 
+// 12.3.6 Find Element From Shadow Root, https://w3c.github.io/webdriver/#find-element-from-shadow-root
+Messages::WebDriverClient::FindElementFromShadowRootResponse WebDriverConnection::find_element_from_shadow_root(JsonValue const& payload, String const& shadow_id)
+{
+    // 1. Let location strategy be the result of getting a property called "using".
+    auto location_strategy_string = TRY(get_property(payload, "using"sv));
+    auto location_strategy = Web::WebDriver::location_strategy_from_string(location_strategy_string);
+
+    // 2. If location strategy is not present as a keyword in the table of location strategies, return error with error code invalid argument.
+    if (!location_strategy.has_value())
+        return Web::WebDriver::Error::from_code(Web::WebDriver::ErrorCode::InvalidArgument, String::formatted("Location strategy '{}' is invalid", location_strategy_string));
+
+    // 3. Let selector be the result of getting a property called "value".
+    // 4. If selector is undefined, return error with error code invalid argument.
+    auto selector = TRY(get_property(payload, "value"sv));
+
+    // 5. If the current browsing context is no longer open, return error with error code no such window.
+    TRY(ensure_open_top_level_browsing_context());
+
+    // FIXME: 6. Handle any user prompts and return its value if it is an error.
+
+    // 7. Let start node be the result of trying to get a known shadow root with url variable shadow id.
+    auto* start_node = TRY(get_known_shadow_root(shadow_id));
+
+    // 8. Let result be the value of trying to Find with start node, location strategy, and selector.
+    auto result = TRY(find(*start_node, *location_strategy, selector));
+
+    // 9. If result is empty, return error with error code no such element. Otherwise, return the first element of result.
+    if (result.is_empty())
+        return Web::WebDriver::Error::from_code(Web::WebDriver::ErrorCode::NoSuchElement, "The requested element does not exist"sv);
+
+    return result.take(0);
+}
+
 // 12.3.8 Get Active Element, https://w3c.github.io/webdriver/#get-active-element
 Messages::WebDriverClient::GetActiveElementResponse WebDriverConnection::get_active_element()
 {

Userland/Services/WebContent/WebDriverConnection.h

@@ -58,6 +58,7 @@ private:
     virtual Messages::WebDriverClient::FindElementsResponse find_elements(JsonValue const& payload) override;
     virtual Messages::WebDriverClient::FindElementFromElementResponse find_element_from_element(JsonValue const& payload, String const& element_id) override;
     virtual Messages::WebDriverClient::FindElementsFromElementResponse find_elements_from_element(JsonValue const& payload, String const& element_id) override;
+    virtual Messages::WebDriverClient::FindElementFromShadowRootResponse find_element_from_shadow_root(JsonValue const& payload, String const& shadow_id) override;
     virtual Messages::WebDriverClient::GetActiveElementResponse get_active_element() override;
     virtual Messages::WebDriverClient::GetElementShadowRootResponse get_element_shadow_root(String const& element_id) override;
     virtual Messages::WebDriverClient::IsElementSelectedResponse is_element_selected(String const& element_id) override;

Userland/Services/WebDriver/Client.cpp

@@ -359,6 +359,15 @@ Web::WebDriver::Response Client::find_elements_from_element(Web::WebDriver::Para
     return session->web_content_connection().find_elements_from_element(payload, parameters[1]);
 }
 
+// 12.3.6 Find Element From Shadow Root, https://w3c.github.io/webdriver/#find-element-from-shadow-root
+// POST /session/{session id}/shadow/{shadow id}/element
+Web::WebDriver::Response Client::find_element_from_shadow_root(Web::WebDriver::Parameters parameters, JsonValue payload)
+{
+    dbgln_if(WEBDRIVER_DEBUG, "Handling POST /session/<session_id>/shadow/<shadow_id>/element");
+    auto* session = TRY(find_session_with_id(parameters[0]));
+    return session->web_content_connection().find_element_from_shadow_root(payload, parameters[1]);
+}
+
 // 12.3.8 Get Active Element, https://w3c.github.io/webdriver/#get-active-element
 // GET /session/{session id}/element/active
 Web::WebDriver::Response Client::get_active_element(Web::WebDriver::Parameters parameters, JsonValue)

Userland/Services/WebDriver/Client.h

@@ -56,6 +56,7 @@ private:
     virtual Web::WebDriver::Response find_elements(Web::WebDriver::Parameters parameters, JsonValue payload) override;
     virtual Web::WebDriver::Response find_element_from_element(Web::WebDriver::Parameters parameters, JsonValue payload) override;
     virtual Web::WebDriver::Response find_elements_from_element(Web::WebDriver::Parameters parameters, JsonValue payload) override;
+    virtual Web::WebDriver::Response find_element_from_shadow_root(Web::WebDriver::Parameters parameters, JsonValue payload) override;
     virtual Web::WebDriver::Response get_active_element(Web::WebDriver::Parameters parameters, JsonValue payload) override;
     virtual Web::WebDriver::Response get_element_shadow_root(Web::WebDriver::Parameters parameters, JsonValue payload) override;
     virtual Web::WebDriver::Response is_element_selected(Web::WebDriver::Parameters parameters, JsonValue payload) override;