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::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        global: &GlobalScope,
167        proto: Option<HandleObject>,
168        can_gc: CanGc,
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_script_url_compliant_string(
176            global,
177            script_url,
178            "Worker",
179            "constructor",
180            can_gc,
181        )?;
182        // Step 2-4.
183        let worker_url = match global.api_base_url().join(&compliant_script_url.str()) {
184            Ok(url) => url,
185            Err(_) => return Err(Error::Syntax(None)),
186        };
187
188        let (sender, receiver) = unbounded();
189        let closing = Arc::new(AtomicBool::new(false));
190        let worker = Worker::new(global, proto, sender.clone(), closing.clone(), can_gc);
191        let worker_ref = Trusted::new(&*worker);
192
193        let worker_load_origin = WorkerScriptLoadOrigin {
194            referrer_url: match global.get_referrer() {
195                Referrer::Client(url) => Some(url),
196                Referrer::ReferrerUrl(url) => Some(url),
197                _ => None,
198            },
199            referrer_policy: global.get_referrer_policy(),
200            pipeline_id: global.pipeline_id(),
201        };
202
203        let webview_id = global
204            .webview_id()
205            .expect("Global object must have a WebViewId");
206        let browsing_context = global
207            .downcast::<Window>()
208            .map(|w| w.window_proxy().browsing_context_id())
209            .or_else(|| {
210                global
211                    .downcast::<DedicatedWorkerGlobalScope>()
212                    .and_then(|w| w.browsing_context())
213            });
214
215        let (devtools_sender, devtools_receiver) = generic_channel::channel().unwrap();
216        let worker_id = WorkerId(Uuid::new_v4());
217        if let Some(chan) = global.devtools_chan() {
218            let pipeline_id = global.pipeline_id();
219            let title = format!("Worker for {}", worker_url);
220            if let Some(browsing_context) = browsing_context {
221                let page_info = DevtoolsPageInfo {
222                    title,
223                    url: worker_url.clone(),
224                    is_top_level_global: false,
225                };
226                let _ = chan.send(ScriptToDevtoolsControlMsg::NewGlobal(
227                    (browsing_context, pipeline_id, Some(worker_id), webview_id),
228                    devtools_sender.clone(),
229                    page_info,
230                ));
231            }
232        }
233
234        let init = prepare_workerscope_init(global, Some(devtools_sender), Some(worker_id));
235
236        let (control_sender, control_receiver) = unbounded();
237        let (context_sender, context_receiver) = unbounded();
238
239        let event_loop_sender = global
240            .event_loop_sender()
241            .expect("Tried to create a worker in a worker while not handling a message?");
242        let join_handle = DedicatedWorkerGlobalScope::run_worker_scope(
243            init,
244            webview_id,
245            worker_url,
246            devtools_receiver,
247            worker_ref,
248            event_loop_sender,
249            sender,
250            receiver,
251            worker_load_origin,
252            String::from(worker_options.name.str()),
253            worker_options.type_,
254            closing.clone(),
255            global.image_cache(),
256            browsing_context,
257            #[cfg(feature = "webgpu")]
258            global.wgpu_id_hub(),
259            control_receiver,
260            context_sender,
261            global.insecure_requests_policy(),
262            global.policy_container(),
263            global.font_context().cloned(),
264        );
265
266        let context = context_receiver
267            .recv()
268            .expect("Couldn't receive a context for worker.");
269
270        worker.set_context_for_interrupt(context.clone());
271        global.track_worker(closing, join_handle, control_sender, context);
272
273        Ok(worker)
274    }
275
276    /// <https://html.spec.whatwg.org/multipage/#dom-worker-postmessage>
277    fn PostMessage(
278        &self,
279        cx: &mut JSContext,
280        message: HandleValue,
281        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
282    ) -> ErrorResult {
283        self.post_message_impl(cx, message, transfer)
284    }
285
286    /// <https://html.spec.whatwg.org/multipage/#dom-worker-postmessage>
287    fn PostMessage_(
288        &self,
289        cx: &mut JSContext,
290        message: HandleValue,
291        options: RootedTraceableBox<StructuredSerializeOptions>,
292    ) -> ErrorResult {
293        let mut rooted = CustomAutoRooter::new(
294            options
295                .transfer
296                .iter()
297                .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
298                .collect(),
299        );
300        #[expect(unsafe_code)]
301        let guard = unsafe { CustomAutoRooterGuard::new(cx.raw_cx(), &mut rooted) };
302        self.post_message_impl(cx, message, guard)
303    }
304
305    /// <https://html.spec.whatwg.org/multipage/#terminate-a-worker>
306    fn Terminate(&self) {
307        // Step 1
308        if self.closing.swap(true, Ordering::SeqCst) {
309            return;
310        }
311
312        // Step 2
313        self.terminated.set(true);
314
315        // Step 3
316        if let Some(cx) = self.context_for_interrupt.borrow().as_ref() {
317            cx.request_interrupt_callback()
318        }
319    }
320
321    // https://html.spec.whatwg.org/multipage/#handler-worker-onmessage
322    event_handler!(message, GetOnmessage, SetOnmessage);
323
324    // https://html.spec.whatwg.org/multipage/#handler-worker-onmessageerror
325    event_handler!(messageerror, GetOnmessageerror, SetOnmessageerror);
326
327    // https://html.spec.whatwg.org/multipage/#handler-workerglobalscope-onerror
328    event_handler!(error, GetOnerror, SetOnerror);
329}
330
331impl TaskOnce for SimpleWorkerErrorHandler<Worker> {
332    #[cfg_attr(crown, expect(crown::unrooted_must_root))]
333    fn run_once(self, cx: &mut JSContext) {
334        Worker::dispatch_simple_error(self.addr, CanGc::from_cx(cx));
335    }
336}
script/dom/workers/worker.rs

script/dom/workers/
worker.rs
