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