Move webdriver actions commands to servoshell (#37669)

Move webdriver actions commands to servoshell.

Testing: Test with webdriver enable in the CI
[Test result
1](https://github.com/longvatrong111/servo/actions/runs/15875355256)
[Test result
2](https://github.com/longvatrong111/servo/actions/runs/15875356595)
[Test result
3](https://github.com/longvatrong111/servo/actions/runs/15875361886)

Fixes: https://github.com/servo/servo/issues/37370

Signed-off-by: batu_hoang <longvatrong111@gmail.com>

components/compositing/compositor.rs

@@ -27,10 +27,10 @@ use constellation_traits::{EmbedderToConstellationMessage, PaintMetricEvent};
 use crossbeam_channel::{Receiver, Sender};
 use dpi::PhysicalSize;
 use embedder_traits::{
-    CompositorHitTestResult, Cursor, InputEvent, MouseButtonEvent, MouseMoveEvent, ShutdownState,
+    CompositorHitTestResult, Cursor, InputEvent, ShutdownState, UntrustedNodeAddress,
-    UntrustedNodeAddress, ViewportDetails, WheelDelta, WheelEvent, WheelMode,
+    ViewportDetails,
 };
-use euclid::{Point2D, Rect, Scale, Size2D, Transform3D, Vector2D};
+use euclid::{Point2D, Rect, Scale, Size2D, Transform3D};
 use ipc_channel::ipc::{self, IpcSharedMemory};
 use libc::c_void;
 use log::{debug, info, trace, warn};
@@ -672,64 +672,6 @@ impl IOCompositor {
                 }
             },
 
-            CompositorMsg::WebDriverMouseButtonEvent(
-                webview_id,
-                action,
-                button,
-                x,
-                y,
-                message_id,
-            ) => {
-                let Some(webview_renderer) = self.webview_renderers.get_mut(webview_id) else {
-                    warn!("Handling input event for unknown webview: {webview_id}");
-                    return;
-                };
-                let dppx = webview_renderer.device_pixels_per_page_pixel();
-                let point = dppx.transform_point(Point2D::new(x, y));
-                webview_renderer.dispatch_point_input_event(
-                    InputEvent::MouseButton(MouseButtonEvent::new(action, button, point))
-                        .with_webdriver_message_id(message_id),
-                );
-            },
-
-            CompositorMsg::WebDriverMouseMoveEvent(webview_id, x, y, message_id) => {
-                let Some(webview_renderer) = self.webview_renderers.get_mut(webview_id) else {
-                    warn!("Handling input event for unknown webview: {webview_id}");
-                    return;
-                };
-                let dppx = webview_renderer.device_pixels_per_page_pixel();
-                let point = dppx.transform_point(Point2D::new(x, y));
-                webview_renderer.dispatch_point_input_event(
-                    InputEvent::MouseMove(MouseMoveEvent::new(point))
-                        .with_webdriver_message_id(message_id),
-                );
-            },
-
-            CompositorMsg::WebDriverWheelScrollEvent(webview_id, x, y, dx, dy, message_id) => {
-                let Some(webview_renderer) = self.webview_renderers.get_mut(webview_id) else {
-                    warn!("Handling input event for unknown webview: {webview_id}");
-                    return;
-                };
-                // The sign of wheel delta value definition in uievent
-                // is inverted compared to `winit`s wheel delta. Hence,
-                // here we invert the sign to mimic wheel scroll
-                // implementation in `headed_window.rs`.
-                let delta = WheelDelta {
-                    x: -dx,
-                    y: -dy,
-                    z: 0.0,
-                    mode: WheelMode::DeltaPixel,
-                };
-                let dppx = webview_renderer.device_pixels_per_page_pixel();
-                let point = dppx.transform_point(Point2D::new(x, y));
-                let scroll_delta = dppx.transform_vector(Vector2D::new(dx as f32, dy as f32));
-                webview_renderer.dispatch_point_input_event(
-                    InputEvent::Wheel(WheelEvent::new(delta, point))
-                        .with_webdriver_message_id(message_id),
-                );
-                webview_renderer.on_webdriver_wheel_action(scroll_delta, point);
-            },
-
             CompositorMsg::SendInitialTransaction(pipeline) => {
                 let mut txn = Transaction::new();
                 txn.set_display_list(WebRenderEpoch(0), (pipeline, Default::default()));

components/compositing/tracing.rs

@@ -40,9 +40,6 @@ mod from_constellation {
                 Self::NewWebRenderFrameReady(..) => target!("NewWebRenderFrameReady"),
                 Self::PipelineExited(..) => target!("PipelineExited"),
                 Self::LoadComplete(..) => target!("LoadComplete"),
-                Self::WebDriverMouseButtonEvent(..) => target!("WebDriverMouseButtonEvent"),
-                Self::WebDriverMouseMoveEvent(..) => target!("WebDriverMouseMoveEvent"),
-                Self::WebDriverWheelScrollEvent(..) => target!("WebDriverWheelScrollEvent"),
                 Self::SendInitialTransaction(..) => target!("SendInitialTransaction"),
                 Self::SendScrollNode(..) => target!("SendScrollNode"),
                 Self::SendDisplayList { .. } => target!("SendDisplayList"),

components/compositing/webview_renderer.rs

@@ -792,22 +792,6 @@ impl WebViewRenderer {
             }));
     }
 
-    /// Push scroll pending event when receiving wheel action from webdriver
-    pub(crate) fn on_webdriver_wheel_action(
-        &mut self,
-        scroll_delta: Vector2D<f32, DevicePixel>,
-        point: Point2D<f32, DevicePixel>,
-    ) {
-        if self.global.borrow().shutdown_state() != ShutdownState::NotShuttingDown {
-            return;
-        }
-
-        let scroll_location =
-            ScrollLocation::Delta(LayoutVector2D::from_untyped(scroll_delta.to_untyped()));
-        let cursor = DeviceIntPoint::new(point.x as i32, point.y as i32);
-        self.on_scroll_window_event(scroll_location, cursor)
-    }
-
     /// Process pending scroll events for this [`WebViewRenderer`]. Returns a tuple containing:
     ///
     ///  - A boolean that is true if a zoom occurred.

components/constellation/constellation.rs

@@ -1468,6 +1468,9 @@ where
                     )
                 }
             },
+            EmbedderToConstellationMessage::SetWebDriverResponseSender(sender) => {
+                self.webdriver.input_command_response_sender = Some(sender);
+            },
         }
     }
 
@@ -1850,7 +1853,6 @@ where
                         .send(WebDriverCommandResponse { id: msg_id })
                         .unwrap_or_else(|_| {
                             warn!("Failed to send WebDriverInputComplete {:?}", msg_id);
-                            self.webdriver.input_command_response_sender = None;
                         });
                 } else {
                     warn!("No WebDriver input_command_response_sender");
@@ -4616,14 +4618,7 @@ where
                     }
                 }
             },
-            WebDriverCommandMsg::KeyboardAction(
+            WebDriverCommandMsg::KeyboardAction(browsing_context_id, key_event, msg_id) => {
-                browsing_context_id,
-                key_event,
-                msg_id,
-                response_sender,
-            ) => {
-                self.webdriver.input_command_response_sender = Some(response_sender);
-
                 let pipeline_id = match self.browsing_contexts.get(&browsing_context_id) {
                     Some(browsing_context) => browsing_context.pipeline_id,
                     None => {
@@ -4649,50 +4644,14 @@ where
                     self.handle_send_error(pipeline_id, e)
                 }
             },
-            WebDriverCommandMsg::MouseButtonAction(
+            WebDriverCommandMsg::MouseButtonAction(..) => {
-                webview_id,
+                unreachable!("This command should be send directly to the embedder.");
-                mouse_event_type,
-                mouse_button,
-                x,
-                y,
-                msg_id,
-                response_sender,
-            ) => {
-                self.webdriver.input_command_response_sender = Some(response_sender);
-
-                self.compositor_proxy
-                    .send(CompositorMsg::WebDriverMouseButtonEvent(
-                        webview_id,
-                        mouse_event_type,
-                        mouse_button,
-                        x,
-                        y,
-                        msg_id,
-                    ));
             },
-            WebDriverCommandMsg::MouseMoveAction(webview_id, x, y, msg_id, response_sender) => {
+            WebDriverCommandMsg::MouseMoveAction(..) => {
-                self.webdriver.input_command_response_sender = Some(response_sender);
+                unreachable!("This command should be send directly to the embedder.");
-
-                self.compositor_proxy
-                    .send(CompositorMsg::WebDriverMouseMoveEvent(
-                        webview_id, x, y, msg_id,
-                    ));
             },
-            WebDriverCommandMsg::WheelScrollAction(
+            WebDriverCommandMsg::WheelScrollAction(..) => {
-                webview_id,
+                unreachable!("This command should be send directly to the embedder.");
-                x,
-                y,
-                delta_x,
-                delta_y,
-                msg_id,
-                response_sender,
-            ) => {
-                self.webdriver.input_command_response_sender = Some(response_sender);
-
-                self.compositor_proxy
-                    .send(CompositorMsg::WebDriverWheelScrollEvent(
-                        webview_id, x, y, delta_x, delta_y, msg_id,
-                    ));
             },
             WebDriverCommandMsg::TakeScreenshot(webview_id, rect, response_sender) => {
                 self.compositor_proxy.send(CompositorMsg::CreatePng(

components/constellation/tracing.rs

@@ -77,6 +77,7 @@ mod from_compositor {
                 Self::EvaluateJavaScript(..) => target!("EvaluateJavaScript"),
                 Self::CreateMemoryReport(..) => target!("CreateMemoryReport"),
                 Self::SendImageKeysForPipeline(..) => target!("SendImageKeysForPipeline"),
+                Self::SetWebDriverResponseSender(..) => target!("SetWebDriverResponseSender"),
             }
         }
     }

components/shared/compositing/lib.rs

@@ -8,10 +8,7 @@ use std::fmt::{Debug, Error, Formatter};
 
 use base::id::{PipelineId, WebViewId};
 use crossbeam_channel::Sender;
-use embedder_traits::{
+use embedder_traits::{AnimationState, EventLoopWaker, TouchEventResult};
-    AnimationState, EventLoopWaker, MouseButton, MouseButtonAction, TouchEventResult,
-    WebDriverMessageId,
-};
 use euclid::Rect;
 use ipc_channel::ipc::IpcSender;
 use log::warn;
@@ -105,20 +102,6 @@ pub enum CompositorMsg {
     PipelineExited(WebViewId, PipelineId, PipelineExitSource),
     /// The load of a page has completed
     LoadComplete(WebViewId),
-    /// WebDriver mouse button event
-    WebDriverMouseButtonEvent(
-        WebViewId,
-        MouseButtonAction,
-        MouseButton,
-        f32,
-        f32,
-        Option<WebDriverMessageId>,
-    ),
-    /// WebDriver mouse move event
-    WebDriverMouseMoveEvent(WebViewId, f32, f32, Option<WebDriverMessageId>),
-    // Webdriver wheel scroll event
-    WebDriverWheelScrollEvent(WebViewId, f32, f32, f64, f64, Option<WebDriverMessageId>),
-
     /// Inform WebRender of the existence of this pipeline.
     SendInitialTransaction(WebRenderPipelineId),
     /// Perform a scroll operation.

components/shared/constellation/lib.rs

@@ -20,7 +20,7 @@ use base::cross_process_instant::CrossProcessInstant;
 use base::id::{MessagePortId, PipelineId, WebViewId};
 use embedder_traits::{
     CompositorHitTestResult, Cursor, InputEvent, JavaScriptEvaluationId, MediaSessionActionType,
-    Theme, ViewportDetails, WebDriverCommandMsg,
+    Theme, ViewportDetails, WebDriverCommandMsg, WebDriverCommandResponse,
 };
 pub use from_script_message::*;
 use ipc_channel::ipc::IpcSender;
@@ -96,6 +96,8 @@ pub enum EmbedderToConstellationMessage {
     CreateMemoryReport(IpcSender<MemoryReportResult>),
     /// Sends the generated image key to the image cache associated with this pipeline.
     SendImageKeysForPipeline(PipelineId, Vec<ImageKey>),
+    /// Set WebDriver input event handled sender.
+    SetWebDriverResponseSender(IpcSender<WebDriverCommandResponse>),
 }
 
 /// A description of a paint metric that is sent from the Servo renderer to the

components/shared/embedder/webdriver.rs

@@ -30,6 +30,9 @@ pub struct WebDriverMessageId(pub usize);
 /// Messages to the constellation originating from the WebDriver server.
 #[derive(Debug, Deserialize, Serialize)]
 pub enum WebDriverCommandMsg {
+    /// Used in the initialization of the WebDriver server to set the sender for sending responses
+    /// back to the WebDriver client. It is set to constellation for now
+    SetWebDriverResponseSender(IpcSender<WebDriverCommandResponse>),
     /// Get the window size.
     GetWindowRect(WebViewId, IpcSender<DeviceIntRect>),
     /// Get the viewport size.
@@ -53,7 +56,6 @@ pub enum WebDriverCommandMsg {
         KeyboardEvent,
         // Should never be None.
         Option<WebDriverMessageId>,
-        IpcSender<WebDriverCommandResponse>,
     ),
     /// Act as if the mouse was clicked in the browsing context with the given ID.
     MouseButtonAction(
@@ -64,7 +66,6 @@ pub enum WebDriverCommandMsg {
         f32,
         // Should never be None.
         Option<WebDriverMessageId>,
-        IpcSender<WebDriverCommandResponse>,
     ),
     /// Act as if the mouse was moved in the browsing context with the given ID.
     MouseMoveAction(
@@ -74,7 +75,6 @@ pub enum WebDriverCommandMsg {
         // None if it's not the last `perform_pointer_move` since we only
         // expect one response from constellation for each tick actions.
         Option<WebDriverMessageId>,
-        IpcSender<WebDriverCommandResponse>,
     ),
     /// Act as if the mouse wheel is scrolled in the browsing context given the given ID.
     WheelScrollAction(
@@ -86,7 +86,6 @@ pub enum WebDriverCommandMsg {
         // None if it's not the last `perform_wheel_scroll` since we only
         // expect one response from constellation for each tick actions.
         Option<WebDriverMessageId>,
-        IpcSender<WebDriverCommandResponse>,
     ),
     /// Set the window size.
     SetWindowSize(

components/webdriver_server/actions.rs

@@ -7,7 +7,6 @@ use std::thread;
 use std::time::{Duration, Instant};
 
 use base::id::BrowsingContextId;
-use constellation_traits::EmbedderToConstellationMessage;
 use embedder_traits::{MouseButtonAction, WebDriverCommandMsg, WebDriverScriptCommand};
 use ipc_channel::ipc;
 use keyboard_types::webdriver::KeyInputState;
@@ -178,7 +177,7 @@ impl Handler {
         //
         // Wait for num_pending_actions number of responses
         for _ in 0..self.num_pending_actions.get() {
-            match self.constellation_receiver.recv() {
+            match self.webdriver_response_receiver.recv() {
                 Ok(response) => {
                     let current_waiting_id = self
                         .current_action_id
@@ -316,11 +315,8 @@ impl Handler {
             self.session().unwrap().browsing_context_id,
             keyboard_event,
             msg_id,
-            self.constellation_sender.clone(),
         );
-        self.constellation_chan
+        let _ = self.send_message_to_embedder(cmd_msg);
-            .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-            .unwrap();
     }
 
     /// <https://w3c.github.io/webdriver/#dfn-dispatch-a-keyup-action>
@@ -358,11 +354,8 @@ impl Handler {
                 self.session().unwrap().browsing_context_id,
                 keyboard_event,
                 msg_id,
-                self.constellation_sender.clone(),
             );
-            self.constellation_chan
+            let _ = self.send_message_to_embedder(cmd_msg);
-                .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-                .unwrap();
         }
     }
 
@@ -390,11 +383,8 @@ impl Handler {
             pointer_input_state.x as f32,
             pointer_input_state.y as f32,
             msg_id,
-            self.constellation_sender.clone(),
         );
-        self.constellation_chan
+        let _ = self.send_message_to_embedder(cmd_msg);
-            .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-            .unwrap();
     }
 
     /// <https://w3c.github.io/webdriver/#dfn-dispatch-a-pointerup-action>
@@ -439,11 +429,8 @@ impl Handler {
             pointer_input_state.x as f32,
             pointer_input_state.y as f32,
             msg_id,
-            self.constellation_sender.clone(),
         );
-        self.constellation_chan
+        let _ = self.send_message_to_embedder(cmd_msg);
-            .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-            .unwrap();
     }
 
     /// <https://w3c.github.io/webdriver/#dfn-dispatch-a-pointermove-action>
@@ -567,11 +554,8 @@ impl Handler {
                     x as f32,
                     y as f32,
                     msg_id,
-                    self.constellation_sender.clone(),
                 );
-                self.constellation_chan
+                let _ = self.send_message_to_embedder(cmd_msg);
-                    .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-                    .unwrap();
                 // Step 7.3
                 pointer_input_state.x = x;
                 pointer_input_state.y = y;
@@ -707,11 +691,8 @@ impl Handler {
                 delta_x as f64,
                 delta_y as f64,
                 msg_id,
-                self.constellation_sender.clone(),
             );
-            self.constellation_chan
+            let _ = self.send_message_to_embedder(cmd_msg);
-                .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-                .unwrap();
 
             curr_delta_x += delta_x;
             curr_delta_y += delta_y;

components/webdriver_server/lib.rs

@@ -127,12 +127,15 @@ pub fn start_server(
     constellation_chan_deprecated: Sender<EmbedderToConstellationMessage>,
     embedder_sender: Sender<WebDriverCommandMsg>,
     event_loop_waker: Box<dyn EventLoopWaker>,
+    webdriver_response_receiver: IpcReceiver<WebDriverCommandResponse>,
 ) {
     let handler = Handler::new(
         constellation_chan_deprecated,
         embedder_sender,
         event_loop_waker,
+        webdriver_response_receiver,
     );
+
     thread::Builder::new()
         .name("WebDriverHttpServer".to_owned())
         .spawn(move || {
@@ -242,12 +245,8 @@ struct Handler {
     /// TODO: change name to constellation_sender
     constellation_chan: Sender<EmbedderToConstellationMessage>,
 
-    /// The IPC sender which we can clone and pass along to the constellation
-    /// TODO: change name to webdriver_response_sender
-    constellation_sender: IpcSender<WebDriverCommandResponse>,
-
     /// Receiver notification from the constellation when a command is completed
-    constellation_receiver: IpcReceiver<WebDriverCommandResponse>,
+    webdriver_response_receiver: IpcReceiver<WebDriverCommandResponse>,
 
     id_generator: WebDriverMessageIdGenerator,
 
@@ -474,6 +473,7 @@ impl Handler {
         constellation_chan: Sender<EmbedderToConstellationMessage>,
         embedder_sender: Sender<WebDriverCommandMsg>,
         event_loop_waker: Box<dyn EventLoopWaker>,
+        webdriver_response_receiver: IpcReceiver<WebDriverCommandResponse>,
     ) -> Handler {
         // Create a pair of both an IPC and a threaded channel,
         // keep the IPC sender to clone and pass to the constellation for each load,
@@ -484,8 +484,6 @@ impl Handler {
         let (sender, load_status_receiver) = unbounded();
         ROUTER.route_ipc_receiver_to_crossbeam_sender(receiver, sender);
 
-        let (constellation_sender, constellation_receiver) = ipc::channel().unwrap();
-
         Handler {
             load_status_sender,
             load_status_receiver,
@@ -493,8 +491,7 @@ impl Handler {
             embedder_sender,
             event_loop_waker,
             constellation_chan,
-            constellation_sender,
+            webdriver_response_receiver,
-            constellation_receiver,
             id_generator: WebDriverMessageIdGenerator::new(),
             current_action_id: Cell::new(None),
             num_pending_actions: Cell::new(0),
@@ -1836,9 +1833,7 @@ impl Handler {
             sender,
         );
         let cmd_msg = WebDriverCommandMsg::ScriptCommand(browsing_context_id, cmd);
-        self.constellation_chan
+        self.send_message_to_embedder(cmd_msg)?;
-            .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-            .unwrap();
 
         // TODO: distinguish the not found and not focusable cases
         // File input and non-typeable form control should have
@@ -1853,9 +1848,7 @@ impl Handler {
         // send keys command being two separate messages,
         // so the constellation may have changed state between them.
         let cmd_msg = WebDriverCommandMsg::SendKeys(browsing_context_id, input_events);
-        self.constellation_chan
+        self.send_message_to_embedder(cmd_msg)?;
-            .send(EmbedderToConstellationMessage::WebDriverCommand(cmd_msg))
-            .unwrap();
 
         Ok(WebDriverResponse::Void)
     }

ports/servoshell/Cargo.toml

@@ -62,6 +62,7 @@ euclid = { workspace = true }
 getopts = { workspace = true }
 hitrace = { workspace = true, optional = true }
 image = { workspace = true }
+ipc-channel = { workspace = true }
 keyboard-types = { workspace = true }
 libc = { workspace = true }
 libservo = { path = "../../components/servo", features = ["background_hang_monitor", "bluetooth", "testbinding"] }
@@ -78,7 +79,6 @@ webdriver_server = { path = "../../components/webdriver_server" }
 
 [target.'cfg(target_os = "android")'.dependencies]
 android_logger = "0.15"
-ipc-channel = { workspace = true }
 jni = "0.21.1"
 
 [target.'cfg(not(target_os = "android"))'.dependencies]

ports/servoshell/desktop/app.rs

@@ -12,14 +12,21 @@ use std::time::Instant;
 use std::{env, fs};
 
 use ::servo::ServoBuilder;
+use constellation_traits::EmbedderToConstellationMessage;
 use crossbeam_channel::unbounded;
+use euclid::{Point2D, Vector2D};
+use ipc_channel::ipc;
 use log::{info, trace, warn};
 use net::protocols::ProtocolRegistry;
 use servo::config::opts::Opts;
 use servo::config::prefs::Preferences;
 use servo::servo_url::ServoUrl;
 use servo::user_content_manager::{UserContentManager, UserScript};
-use servo::{EventLoopWaker, WebDriverCommandMsg};
+use servo::webrender_api::ScrollLocation;
+use servo::{
+    EventLoopWaker, InputEvent, MouseButtonEvent, MouseMoveEvent, WebDriverCommandMsg, WheelDelta,
+    WheelEvent, WheelMode,
+};
 use url::Url;
 use winit::application::ApplicationHandler;
 use winit::event::WindowEvent;
@@ -162,15 +169,25 @@ impl App {
         // Initialize WebDriver server here before `servo` is moved.
         let webdriver_receiver = self.servoshell_preferences.webdriver_port.map(|port| {
             let (embedder_sender, embedder_receiver) = unbounded();
+            let (webdriver_response_sender, webdriver_response_receiver) = ipc::channel().unwrap();
+
+            // Set the WebDriver response sender to constellation.
+            // TODO: consider using Servo API to notify embedder about input events completions
+            servo
+                .constellation_sender()
+                .send(EmbedderToConstellationMessage::SetWebDriverResponseSender(
+                    webdriver_response_sender,
+                ))
+                .unwrap_or_else(|_| {
+                    warn!("Failed to set WebDriver response sender in constellation");
+                });
 
-            // TODO: WebDriver will no longer need this channel once all WebDriver
-            // commands are executed via the Servo API.
-            let constellation_sender_deprecated = servo.constellation_sender();
             webdriver_server::start_server(
                 port,
-                constellation_sender_deprecated,
+                servo.constellation_sender(),
                 embedder_sender,
                 self.waker.clone(),
+                webdriver_response_receiver,
             );
 
             embedder_receiver
@@ -331,6 +348,9 @@ impl App {
 
         while let Ok(msg) = webdriver_receiver.try_recv() {
             match msg {
+                WebDriverCommandMsg::SetWebDriverResponseSender(..) => {
+                    running_state.forward_webdriver_command(msg);
+                },
                 WebDriverCommandMsg::IsWebViewOpen(webview_id, sender) => {
                     let context = running_state.webview_by_id(webview_id);
 
@@ -338,8 +358,8 @@ impl App {
                         warn!("Failed to send response of IsWebViewOpein: {error}");
                     }
                 },
-                webdriver_msg @ WebDriverCommandMsg::IsBrowsingContextOpen(..) => {
+                WebDriverCommandMsg::IsBrowsingContextOpen(..) => {
-                    running_state.forward_webdriver_command(webdriver_msg);
+                    running_state.forward_webdriver_command(msg);
                 },
                 WebDriverCommandMsg::NewWebView(response_sender, load_status_sender) => {
                     let new_webview =
@@ -434,11 +454,68 @@ impl App {
                         webview.go_forward(1);
                     }
                 },
-                WebDriverCommandMsg::SendKeys(..) |
+                // Key events don't need hit test so can be forwarded to constellation for now
-                WebDriverCommandMsg::KeyboardAction(..) |
+                WebDriverCommandMsg::SendKeys(..) => {
-                WebDriverCommandMsg::MouseButtonAction(..) |
+                    running_state.forward_webdriver_command(msg);
-                WebDriverCommandMsg::MouseMoveAction(..) |
+                },
-                WebDriverCommandMsg::WheelScrollAction(..) |
+                WebDriverCommandMsg::KeyboardAction(..) => {
+                    running_state.forward_webdriver_command(msg);
+                },
+                WebDriverCommandMsg::MouseButtonAction(
+                    webview_id,
+                    mouse_event_type,
+                    mouse_button,
+                    x,
+                    y,
+                    webdriver_message_id,
+                ) => {
+                    if let Some(webview) = running_state.webview_by_id(webview_id) {
+                        webview.notify_input_event(
+                            InputEvent::MouseButton(MouseButtonEvent::new(
+                                mouse_event_type,
+                                mouse_button,
+                                Point2D::new(x, y),
+                            ))
+                            .with_webdriver_message_id(webdriver_message_id),
+                        );
+                    }
+                },
+                WebDriverCommandMsg::MouseMoveAction(webview_id, x, y, webdriver_message_id) => {
+                    if let Some(webview) = running_state.webview_by_id(webview_id) {
+                        webview.notify_input_event(
+                            InputEvent::MouseMove(MouseMoveEvent::new(Point2D::new(x, y)))
+                                .with_webdriver_message_id(webdriver_message_id),
+                        );
+                    }
+                },
+                WebDriverCommandMsg::WheelScrollAction(
+                    webview_id,
+                    x,
+                    y,
+                    dx,
+                    dy,
+                    webdriver_message_id,
+                ) => {
+                    if let Some(webview) = running_state.webview_by_id(webview_id) {
+                        let delta = WheelDelta {
+                            x: -dx,
+                            y: -dy,
+                            z: 0.0,
+                            mode: WheelMode::DeltaPixel,
+                        };
+
+                        let point = Point2D::new(x, y);
+                        let scroll_location =
+                            ScrollLocation::Delta(Vector2D::new(dx as f32, dy as f32));
+
+                        webview.notify_input_event(
+                            InputEvent::Wheel(WheelEvent::new(delta, point))
+                                .with_webdriver_message_id(webdriver_message_id),
+                        );
+
+                        webview.notify_scroll_event(scroll_location, point.to_i32());
+                    }
+                },
                 WebDriverCommandMsg::ScriptCommand(..) |
                 WebDriverCommandMsg::TakeScreenshot(..) => {
                     warn!(