script/dom/workers/
worker.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::cell::Cell;
6use std::sync::Arc;
7use std::sync::atomic::{AtomicBool, Ordering};
8
9use base::generic_channel;
10use constellation_traits::{StructuredSerializedData, WorkerScriptLoadOrigin};
11use crossbeam_channel::{Sender, unbounded};
12use devtools_traits::{DevtoolsPageInfo, ScriptToDevtoolsControlMsg, WorkerId};
13use dom_struct::dom_struct;
14use js::context::JSContext;
15use js::jsapi::{Heap, JSObject};
16use js::jsval::UndefinedValue;
17use js::rust::{CustomAutoRooter, CustomAutoRooterGuard, HandleObject, HandleValue};
18use net_traits::request::Referrer;
19use uuid::Uuid;
20
21use crate::dom::abstractworker::{MessageData, SimpleWorkerErrorHandler, WorkerScriptMsg};
22use crate::dom::bindings::cell::DomRefCell;
23use crate::dom::bindings::codegen::Bindings::MessagePortBinding::StructuredSerializeOptions;
24use crate::dom::bindings::codegen::Bindings::WorkerBinding::{WorkerMethods, WorkerOptions};
25use crate::dom::bindings::codegen::UnionTypes::TrustedScriptURLOrUSVString;
26use crate::dom::bindings::error::{Error, ErrorResult, Fallible};
27use crate::dom::bindings::inheritance::Castable;
28use crate::dom::bindings::refcounted::Trusted;
29use crate::dom::bindings::reflector::{DomGlobal, reflect_dom_object_with_proto};
30use crate::dom::bindings::root::DomRoot;
31use crate::dom::bindings::structuredclone;
32use crate::dom::bindings::trace::{CustomTraceable, RootedTraceableBox};
33use crate::dom::dedicatedworkerglobalscope::{
34    DedicatedWorkerGlobalScope, DedicatedWorkerScriptMsg,
35};
36use crate::dom::eventtarget::EventTarget;
37use crate::dom::globalscope::GlobalScope;
38use crate::dom::messageevent::MessageEvent;
39use crate::dom::trustedtypes::trustedscripturl::TrustedScriptURL;
40use crate::dom::window::Window;
41use crate::dom::workerglobalscope::prepare_workerscope_init;
42use crate::realms::enter_auto_realm;
43use crate::script_runtime::{CanGc, ThreadSafeJSContext};
44use crate::task::TaskOnce;
45
46pub(crate) type TrustedWorkerAddress = Trusted<Worker>;
47
48// https://html.spec.whatwg.org/multipage/#worker
49#[dom_struct]
50pub(crate) struct Worker {
51    eventtarget: EventTarget,
52    /// Sender to the Receiver associated with the DedicatedWorkerGlobalScope
53    /// this Worker created.
54    sender: Sender<DedicatedWorkerScriptMsg>,
55    #[conditional_malloc_size_of]
56    closing: Arc<AtomicBool>,
57    terminated: Cell<bool>,
58    #[ignore_malloc_size_of = "mozjs"]
59    #[no_trace]
60    context_for_interrupt: DomRefCell<Option<ThreadSafeJSContext>>,
61}
62
63impl Worker {
64    fn new_inherited(sender: Sender<DedicatedWorkerScriptMsg>, closing: Arc<AtomicBool>) -> Worker {
65        Worker {
66            eventtarget: EventTarget::new_inherited(),
67            sender,
68            closing,
69            terminated: Cell::new(false),
70            context_for_interrupt: Default::default(),
71        }
72    }
73
74    fn new(
75        global: &GlobalScope,
76        proto: Option<HandleObject>,
77        sender: Sender<DedicatedWorkerScriptMsg>,
78        closing: Arc<AtomicBool>,
79        can_gc: CanGc,
80    ) -> DomRoot<Worker> {
81        reflect_dom_object_with_proto(
82            Box::new(Worker::new_inherited(sender, closing)),
83            global,
84            proto,
85            can_gc,
86        )
87    }
88
89    pub(crate) fn is_terminated(&self) -> bool {
90        self.terminated.get()
91    }
92
93    pub(crate) fn set_context_for_interrupt(&self, cx: ThreadSafeJSContext) {
94        assert!(
95            self.context_for_interrupt.borrow().is_none(),
96            "Context for interrupt must be set only once"
97        );
98        *self.context_for_interrupt.borrow_mut() = Some(cx);
99    }
100
101    pub(crate) fn handle_message(
102        address: TrustedWorkerAddress,
103        data: StructuredSerializedData,
104        cx: &mut JSContext,
105    ) {
106        let worker = address.root();
107
108        if worker.is_terminated() {
109            return;
110        }
111
112        let global = worker.global();
113        let target = worker.upcast();
114        let mut realm = enter_auto_realm(cx, target);
115        let cx = &mut realm.current_realm();
116        rooted!(&in(cx) let mut message = UndefinedValue());
117        if let Ok(ports) =
118            structuredclone::read(&global, data, message.handle_mut(), CanGc::from_cx(cx))
119        {
120            MessageEvent::dispatch_jsval(
121                target,
122                &global,
123                message.handle(),
124                None,
125                None,
126                ports,
127                CanGc::from_cx(cx),
128            );
129        } else {
130            // Step 4 of the "port post message steps" of the implicit messageport, fire messageerror.
131            MessageEvent::dispatch_error(target, &global, CanGc::from_cx(cx));
132        }
133    }
134
135    pub(crate) fn dispatch_simple_error(address: TrustedWorkerAddress, can_gc: CanGc) {
136        let worker = address.root();
137        worker.upcast().fire_event(atom!("error"), can_gc);
138    }
139
140    /// <https://html.spec.whatwg.org/multipage/#dom-dedicatedworkerglobalscope-postmessage>
141    fn post_message_impl(
142        &self,
143        cx: &mut JSContext,
144        message: HandleValue,
145        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
146    ) -> ErrorResult {
147        let data = structuredclone::write(cx.into(), message, Some(transfer))?;
148        let address = Trusted::new(self);
149
150        // NOTE: step 9 of https://html.spec.whatwg.org/multipage/#dom-messageport-postmessage
151        // indicates that a nonexistent communication channel should result in a silent error.
152        let _ = self.sender.send(DedicatedWorkerScriptMsg::CommonWorker(
153            address,
154            WorkerScriptMsg::DOMMessage(MessageData {
155                origin: self.global().origin().immutable().clone(),
156                data: Box::new(data),
157            }),
158        ));
159        Ok(())
160    }
161}
162
163impl WorkerMethods<crate::DomTypeHolder> for Worker {
164    // https://html.spec.whatwg.org/multipage/#dom-worker
165    fn Constructor(
166        cx: &mut js::context::JSContext,
167        global: &GlobalScope,
168        proto: Option<HandleObject>,
169        script_url: TrustedScriptURLOrUSVString,
170        worker_options: &WorkerOptions,
171    ) -> Fallible<DomRoot<Worker>> {
172        // Step 1: Let compliantScriptURL be the result of invoking the
173        // Get Trusted Type compliant string algorithm with TrustedScriptURL,
174        // this's relevant global object, scriptURL, "Worker constructor", and "script".
175        let compliant_script_url = TrustedScriptURL::get_trusted_type_compliant_string(
176            cx,
177            global,
178            script_url,
179            "Worker constructor",
180        )?;
181        // Step 2-4.
182        let worker_url = match global.api_base_url().join(&compliant_script_url.str()) {
183            Ok(url) => url,
184            Err(_) => return Err(Error::Syntax(None)),
185        };
186
187        let (sender, receiver) = unbounded();
188        let closing = Arc::new(AtomicBool::new(false));
189        let worker = Worker::new(
190            global,
191            proto,
192            sender.clone(),
193            closing.clone(),
194            CanGc::from_cx(cx),
195        );
196        let worker_ref = Trusted::new(&*worker);
197
198        let worker_load_origin = WorkerScriptLoadOrigin {
199            referrer_url: match global.get_referrer() {
200                Referrer::Client(url) => Some(url),
201                Referrer::ReferrerUrl(url) => Some(url),
202                _ => None,
203            },
204            referrer_policy: global.get_referrer_policy(),
205            pipeline_id: global.pipeline_id(),
206        };
207
208        let webview_id = global
209            .webview_id()
210            .expect("Global object must have a WebViewId");
211        let browsing_context = global
212            .downcast::<Window>()
213            .map(|w| w.window_proxy().browsing_context_id())
214            .or_else(|| {
215                global
216                    .downcast::<DedicatedWorkerGlobalScope>()
217                    .and_then(|w| w.browsing_context())
218            });
219
220        let (devtools_sender, devtools_receiver) = generic_channel::channel().unwrap();
221        let worker_id = WorkerId(Uuid::new_v4());
222        if let Some(chan) = global.devtools_chan() {
223            let pipeline_id = global.pipeline_id();
224            let title = format!("Worker for {}", worker_url);
225            if let Some(browsing_context) = browsing_context {
226                let page_info = DevtoolsPageInfo {
227                    title,
228                    url: worker_url.clone(),
229                    is_top_level_global: false,
230                };
231                let _ = chan.send(ScriptToDevtoolsControlMsg::NewGlobal(
232                    (browsing_context, pipeline_id, Some(worker_id), webview_id),
233                    devtools_sender.clone(),
234                    page_info,
235                ));
236            }
237        }
238
239        let init = prepare_workerscope_init(global, Some(devtools_sender), Some(worker_id));
240
241        let (control_sender, control_receiver) = unbounded();
242        let (context_sender, context_receiver) = unbounded();
243
244        let event_loop_sender = global
245            .event_loop_sender()
246            .expect("Tried to create a worker in a worker while not handling a message?");
247        let join_handle = DedicatedWorkerGlobalScope::run_worker_scope(
248            init,
249            webview_id,
250            worker_url,
251            devtools_receiver,
252            worker_ref,
253            event_loop_sender,
254            sender,
255            receiver,
256            worker_load_origin,
257            String::from(worker_options.name.str()),
258            worker_options.type_,
259            closing.clone(),
260            global.image_cache(),
261            browsing_context,
262            #[cfg(feature = "webgpu")]
263            global.wgpu_id_hub(),
264            control_receiver,
265            context_sender,
266            global.insecure_requests_policy(),
267            global.policy_container(),
268            global.font_context().cloned(),
269        );
270
271        let context = context_receiver
272            .recv()
273            .expect("Couldn't receive a context for worker.");
274
275        worker.set_context_for_interrupt(context.clone());
276        global.track_worker(closing, join_handle, control_sender, context);
277
278        Ok(worker)
279    }
280
281    /// <https://html.spec.whatwg.org/multipage/#dom-worker-postmessage>
282    fn PostMessage(
283        &self,
284        cx: &mut JSContext,
285        message: HandleValue,
286        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
287    ) -> ErrorResult {
288        self.post_message_impl(cx, message, transfer)
289    }
290
291    /// <https://html.spec.whatwg.org/multipage/#dom-worker-postmessage>
292    fn PostMessage_(
293        &self,
294        cx: &mut JSContext,
295        message: HandleValue,
296        options: RootedTraceableBox<StructuredSerializeOptions>,
297    ) -> ErrorResult {
298        let mut rooted = CustomAutoRooter::new(
299            options
300                .transfer
301                .iter()
302                .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
303                .collect(),
304        );
305        #[expect(unsafe_code)]
306        let guard = unsafe { CustomAutoRooterGuard::new(cx.raw_cx(), &mut rooted) };
307        self.post_message_impl(cx, message, guard)
308    }
309
310    /// <https://html.spec.whatwg.org/multipage/#terminate-a-worker>
311    fn Terminate(&self) {
312        // Step 1
313        if self.closing.swap(true, Ordering::SeqCst) {
314            return;
315        }
316
317        // Step 2
318        self.terminated.set(true);
319
320        // Step 3
321        if let Some(cx) = self.context_for_interrupt.borrow().as_ref() {
322            cx.request_interrupt_callback()
323        }
324    }
325
326    // https://html.spec.whatwg.org/multipage/#handler-worker-onmessage
327    event_handler!(message, GetOnmessage, SetOnmessage);
328
329    // https://html.spec.whatwg.org/multipage/#handler-worker-onmessageerror
330    event_handler!(messageerror, GetOnmessageerror, SetOnmessageerror);
331
332    // https://html.spec.whatwg.org/multipage/#handler-workerglobalscope-onerror
333    event_handler!(error, GetOnerror, SetOnerror);
334}
335
336impl TaskOnce for SimpleWorkerErrorHandler<Worker> {
337    #[cfg_attr(crown, expect(crown::unrooted_must_root))]
338    fn run_once(self, cx: &mut JSContext) {
339        Worker::dispatch_simple_error(self.addr, CanGc::from_cx(cx));
340    }
341}
script/dom/workers/worker.rs

script/dom/workers/
worker.rs
