// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license. use crate::colors; use crate::inspector_server::InspectorServer; use crate::js; use crate::ops; use crate::ops::io::Stdio; use crate::permissions::PermissionsContainer; use crate::tokio_util::run_local; use crate::worker::FormatJsErrorFn; use crate::BootstrapOptions; use deno_broadcast_channel::InMemoryBroadcastChannel; use deno_cache::CreateCache; use deno_cache::SqliteBackedCache; use deno_core::error::AnyError; use deno_core::error::JsError; use deno_core::futures::channel::mpsc; use deno_core::futures::future::poll_fn; use deno_core::futures::stream::StreamExt; use deno_core::futures::task::AtomicWaker; use deno_core::located_script_name; use deno_core::serde::Deserialize; use deno_core::serde::Serialize; use deno_core::serde_json::json; use deno_core::v8; use deno_core::CancelHandle; use deno_core::CompiledWasmModuleStore; use deno_core::Extension; use deno_core::GetErrorClassFn; use deno_core::JsRuntime; use deno_core::ModuleId; use deno_core::ModuleLoader; use deno_core::ModuleSpecifier; use deno_core::RuntimeOptions; use deno_core::SharedArrayBufferStore; use deno_core::Snapshot; use deno_core::SourceMapGetter; use deno_node::RequireNpmResolver; use deno_tls::rustls::RootCertStore; use deno_web::create_entangled_message_port; use deno_web::BlobStore; use deno_web::MessagePort; use log::debug; use std::cell::RefCell; use std::fmt; use std::rc::Rc; use std::sync::atomic::AtomicBool; use std::sync::atomic::Ordering; use std::sync::Arc; use std::task::Context; use std::task::Poll; #[derive(Debug, Copy, Clone, PartialEq, Eq, Serialize, Deserialize)] #[serde(rename_all = "lowercase")] pub enum WebWorkerType { Classic, Module, } #[derive( Debug, Default, Copy, Clone, PartialEq, Eq, Hash, Serialize, Deserialize, )] pub struct WorkerId(u32); impl fmt::Display for WorkerId { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "worker-{}", self.0) } } impl WorkerId { pub fn next(&self) -> Option { self.0.checked_add(1).map(WorkerId) } } /// Events that are sent to host from child /// worker. pub enum WorkerControlEvent { Error(AnyError), TerminalError(AnyError), Close, } use deno_core::serde::Serializer; impl Serialize for WorkerControlEvent { fn serialize(&self, serializer: S) -> Result where S: Serializer, { let type_id = match &self { WorkerControlEvent::TerminalError(_) => 1_i32, WorkerControlEvent::Error(_) => 2_i32, WorkerControlEvent::Close => 3_i32, }; match self { WorkerControlEvent::TerminalError(error) | WorkerControlEvent::Error(error) => { let value = match error.downcast_ref::() { Some(js_error) => { let frame = js_error.frames.iter().find(|f| match &f.file_name { Some(s) => !s.trim_start_matches('[').starts_with("deno:"), None => false, }); json!({ "message": js_error.exception_message, "fileName": frame.map(|f| f.file_name.as_ref()), "lineNumber": frame.map(|f| f.line_number.as_ref()), "columnNumber": frame.map(|f| f.column_number.as_ref()), }) } None => json!({ "message": error.to_string(), }), }; Serialize::serialize(&(type_id, value), serializer) } _ => Serialize::serialize(&(type_id, ()), serializer), } } } // Channels used for communication with worker's parent #[derive(Clone)] pub struct WebWorkerInternalHandle { sender: mpsc::Sender, pub port: Rc, pub cancel: Rc, termination_signal: Arc, has_terminated: Arc, terminate_waker: Arc, isolate_handle: v8::IsolateHandle, pub name: String, pub worker_type: WebWorkerType, } impl WebWorkerInternalHandle { /// Post WorkerEvent to parent as a worker pub fn post_event(&self, event: WorkerControlEvent) -> Result<(), AnyError> { let mut sender = self.sender.clone(); // If the channel is closed, // the worker must have terminated but the termination message has not yet been received. // // Therefore just treat it as if the worker has terminated and return. if sender.is_closed() { self.has_terminated.store(true, Ordering::SeqCst); return Ok(()); } sender.try_send(event)?; Ok(()) } /// Check if this worker is terminated or being terminated pub fn is_terminated(&self) -> bool { self.has_terminated.load(Ordering::SeqCst) } /// Check if this worker must terminate (because the termination signal is /// set), and terminates it if so. Returns whether the worker is terminated or /// being terminated, as with [`Self::is_terminated()`]. pub fn terminate_if_needed(&mut self) -> bool { let has_terminated = self.is_terminated(); if !has_terminated && self.termination_signal.load(Ordering::SeqCst) { self.terminate(); return true; } has_terminated } /// Terminate the worker /// This function will set terminated to true, terminate the isolate and close the message channel pub fn terminate(&mut self) { self.cancel.cancel(); // This function can be called multiple times by whomever holds // the handle. However only a single "termination" should occur so // we need a guard here. let already_terminated = self.has_terminated.swap(true, Ordering::SeqCst); if !already_terminated { // Stop javascript execution self.isolate_handle.terminate_execution(); } // Wake parent by closing the channel self.sender.close_channel(); } } pub struct SendableWebWorkerHandle { port: MessagePort, receiver: mpsc::Receiver, termination_signal: Arc, has_terminated: Arc, terminate_waker: Arc, isolate_handle: v8::IsolateHandle, } impl From for WebWorkerHandle { fn from(handle: SendableWebWorkerHandle) -> Self { WebWorkerHandle { receiver: Rc::new(RefCell::new(handle.receiver)), port: Rc::new(handle.port), termination_signal: handle.termination_signal, has_terminated: handle.has_terminated, terminate_waker: handle.terminate_waker, isolate_handle: handle.isolate_handle, } } } /// This is the handle to the web worker that the parent thread uses to /// communicate with the worker. It is created from a `SendableWebWorkerHandle` /// which is sent to the parent thread from the worker thread where it is /// created. The reason for this separation is that the handle first needs to be /// `Send` when transferring between threads, and then must be `Clone` when it /// has arrived on the parent thread. It can not be both at once without large /// amounts of Arc and other fun stuff. #[derive(Clone)] pub struct WebWorkerHandle { pub port: Rc, receiver: Rc>>, termination_signal: Arc, has_terminated: Arc, terminate_waker: Arc, isolate_handle: v8::IsolateHandle, } impl WebWorkerHandle { /// Get the WorkerEvent with lock /// Return error if more than one listener tries to get event pub async fn get_control_event( &self, ) -> Result, AnyError> { #![allow(clippy::await_holding_refcell_ref)] // TODO(ry) remove! let mut receiver = self.receiver.borrow_mut(); Ok(receiver.next().await) } /// Terminate the worker /// This function will set the termination signal, close the message channel, /// and schedule to terminate the isolate after two seconds. pub fn terminate(self) { use std::thread::{sleep, spawn}; use std::time::Duration; let schedule_termination = !self.termination_signal.swap(true, Ordering::SeqCst); self.port.disentangle(); if schedule_termination && !self.has_terminated.load(Ordering::SeqCst) { // Wake up the worker's event loop so it can terminate. self.terminate_waker.wake(); let has_terminated = self.has_terminated.clone(); // Schedule to terminate the isolate's execution. spawn(move || { sleep(Duration::from_secs(2)); // A worker's isolate can only be terminated once, so we need a guard // here. let already_terminated = has_terminated.swap(true, Ordering::SeqCst); if !already_terminated { // Stop javascript execution self.isolate_handle.terminate_execution(); } }); } } } fn create_handles( isolate_handle: v8::IsolateHandle, name: String, worker_type: WebWorkerType, ) -> (WebWorkerInternalHandle, SendableWebWorkerHandle) { let (parent_port, worker_port) = create_entangled_message_port(); let (ctrl_tx, ctrl_rx) = mpsc::channel::(1); let termination_signal = Arc::new(AtomicBool::new(false)); let has_terminated = Arc::new(AtomicBool::new(false)); let terminate_waker = Arc::new(AtomicWaker::new()); let internal_handle = WebWorkerInternalHandle { name, port: Rc::new(parent_port), termination_signal: termination_signal.clone(), has_terminated: has_terminated.clone(), terminate_waker: terminate_waker.clone(), isolate_handle: isolate_handle.clone(), cancel: CancelHandle::new_rc(), sender: ctrl_tx, worker_type, }; let external_handle = SendableWebWorkerHandle { receiver: ctrl_rx, port: worker_port, termination_signal, has_terminated, terminate_waker, isolate_handle, }; (internal_handle, external_handle) } /// This struct is an implementation of `Worker` Web API /// /// Each `WebWorker` is either a child of `MainWorker` or other /// `WebWorker`. pub struct WebWorker { id: WorkerId, pub js_runtime: JsRuntime, pub name: String, internal_handle: WebWorkerInternalHandle, pub worker_type: WebWorkerType, pub main_module: ModuleSpecifier, poll_for_messages_fn: Option>, } pub struct WebWorkerOptions { pub bootstrap: BootstrapOptions, pub extensions: Vec, pub startup_snapshot: Option, pub unsafely_ignore_certificate_errors: Option>, pub root_cert_store: Option, pub seed: Option, pub module_loader: Rc, pub npm_resolver: Option>, pub create_web_worker_cb: Arc, pub preload_module_cb: Arc, pub pre_execute_module_cb: Arc, pub format_js_error_fn: Option>, pub source_map_getter: Option>, pub worker_type: WebWorkerType, pub maybe_inspector_server: Option>, pub get_error_class_fn: Option, pub blob_store: BlobStore, pub broadcast_channel: InMemoryBroadcastChannel, pub shared_array_buffer_store: Option, pub compiled_wasm_module_store: Option, pub cache_storage_dir: Option, pub stdio: Stdio, } impl WebWorker { pub fn bootstrap_from_options( name: String, permissions: PermissionsContainer, main_module: ModuleSpecifier, worker_id: WorkerId, options: WebWorkerOptions, ) -> (Self, SendableWebWorkerHandle) { let bootstrap_options = options.bootstrap.clone(); let (mut worker, handle) = Self::from_options(name, permissions, main_module, worker_id, options); worker.bootstrap(&bootstrap_options); (worker, handle) } pub fn from_options( name: String, permissions: PermissionsContainer, main_module: ModuleSpecifier, worker_id: WorkerId, mut options: WebWorkerOptions, ) -> (Self, SendableWebWorkerHandle) { // Permissions: many ops depend on this let unstable = options.bootstrap.unstable; let enable_testing_features = options.bootstrap.enable_testing_features; let perm_ext = Extension::builder("deno_permissions_web_worker") .state(move |state| { state.put::(permissions.clone()); state.put(ops::UnstableChecker { unstable }); state.put(ops::TestingFeaturesEnabled(enable_testing_features)); Ok(()) }) .build(); let create_cache = options.cache_storage_dir.map(|storage_dir| { let create_cache_fn = move || SqliteBackedCache::new(storage_dir.clone()); CreateCache(Arc::new(create_cache_fn)) }); let mut extensions: Vec = vec![ // Web APIs deno_webidl::init(), deno_console::init(), deno_url::init(), deno_web::init::( options.blob_store.clone(), Some(main_module.clone()), ), deno_fetch::init::(deno_fetch::Options { user_agent: options.bootstrap.user_agent.clone(), root_cert_store: options.root_cert_store.clone(), unsafely_ignore_certificate_errors: options .unsafely_ignore_certificate_errors .clone(), file_fetch_handler: Rc::new(deno_fetch::FsFetchHandler), ..Default::default() }), deno_cache::init::(create_cache), deno_websocket::init::( options.bootstrap.user_agent.clone(), options.root_cert_store.clone(), options.unsafely_ignore_certificate_errors.clone(), ), deno_webstorage::init(None).disable(), deno_broadcast_channel::init(options.broadcast_channel.clone(), unstable), deno_crypto::init(options.seed), deno_webgpu::init(unstable), // ffi deno_ffi::init::(unstable), // Runtime ops that are always initialized for WebWorkers ops::web_worker::init(), ops::runtime::init(main_module.clone()), ops::worker_host::init( options.create_web_worker_cb.clone(), options.preload_module_cb.clone(), options.pre_execute_module_cb.clone(), options.format_js_error_fn.clone(), ), // Extensions providing Deno.* features ops::fs_events::init(), ops::fs::init(), ops::io::init(), ops::io::init_stdio(options.stdio), deno_tls::init(), deno_net::init::( options.root_cert_store.clone(), unstable, options.unsafely_ignore_certificate_errors.clone(), ), deno_napi::init::(unstable), deno_node::init::(options.npm_resolver), ops::os::init_for_worker(), ops::permissions::init(), ops::process::init(), ops::spawn::init(), ops::signal::init(), ops::tty::init(), deno_http::init(), deno_flash::init::(unstable), ops::http::init(), // Permissions ext (worker specific state) perm_ext, ]; // Append exts extensions.extend(std::mem::take(&mut options.extensions)); let mut js_runtime = JsRuntime::new(RuntimeOptions { module_loader: Some(options.module_loader.clone()), startup_snapshot: Some( options .startup_snapshot .unwrap_or_else(js::deno_isolate_init), ), source_map_getter: options.source_map_getter, get_error_class_fn: options.get_error_class_fn, shared_array_buffer_store: options.shared_array_buffer_store.clone(), compiled_wasm_module_store: options.compiled_wasm_module_store.clone(), extensions, inspector: options.maybe_inspector_server.is_some(), ..Default::default() }); if let Some(server) = options.maybe_inspector_server.clone() { server.register_inspector( main_module.to_string(), &mut js_runtime, false, ); // Put inspector handle into the op state so we can put a breakpoint when // executing a CJS entrypoint. let op_state = js_runtime.op_state(); let inspector = js_runtime.inspector(); op_state.borrow_mut().put(inspector); } let (internal_handle, external_handle) = { let handle = js_runtime.v8_isolate().thread_safe_handle(); let (internal_handle, external_handle) = create_handles(handle, name.clone(), options.worker_type); let op_state = js_runtime.op_state(); let mut op_state = op_state.borrow_mut(); op_state.put(internal_handle.clone()); (internal_handle, external_handle) }; ( Self { id: worker_id, js_runtime, name, internal_handle, worker_type: options.worker_type, main_module, poll_for_messages_fn: None, }, external_handle, ) } pub fn bootstrap(&mut self, options: &BootstrapOptions) { // Instead of using name for log we use `worker-${id}` because // WebWorkers can have empty string as name. let script = format!( "bootstrap.workerRuntime({}, \"{}\", \"{}\")", options.as_json(), self.name, self.id ); self .execute_script(&located_script_name!(), &script) .expect("Failed to execute worker bootstrap script"); // Save a reference to function that will start polling for messages // from a worker host; it will be called after the user code is loaded. let script = r#" const pollForMessages = globalThis.pollForMessages; delete globalThis.pollForMessages; pollForMessages "#; let poll_for_messages_fn = self .js_runtime .execute_script(&located_script_name!(), script) .expect("Failed to execute worker bootstrap script"); self.poll_for_messages_fn = Some(poll_for_messages_fn); } /// See [JsRuntime::execute_script](deno_core::JsRuntime::execute_script) pub fn execute_script( &mut self, name: &str, source_code: &str, ) -> Result<(), AnyError> { self.js_runtime.execute_script(name, source_code)?; Ok(()) } /// Loads and instantiates specified JavaScript module as "main" module. pub async fn preload_main_module( &mut self, module_specifier: &ModuleSpecifier, ) -> Result { self .js_runtime .load_main_module(module_specifier, None) .await } /// Loads and instantiates specified JavaScript module as "side" module. pub async fn preload_side_module( &mut self, module_specifier: &ModuleSpecifier, ) -> Result { self .js_runtime .load_side_module(module_specifier, None) .await } /// Loads, instantiates and executes specified JavaScript module. /// /// This method assumes that worker can't be terminated when executing /// side module code. pub async fn execute_side_module( &mut self, module_specifier: &ModuleSpecifier, ) -> Result<(), AnyError> { let id = self.preload_side_module(module_specifier).await?; let mut receiver = self.js_runtime.mod_evaluate(id); tokio::select! { biased; maybe_result = &mut receiver => { debug!("received module evaluate {:#?}", maybe_result); maybe_result.expect("Module evaluation result not provided.") } event_loop_result = self.js_runtime.run_event_loop(false) => { event_loop_result?; let maybe_result = receiver.await; maybe_result.expect("Module evaluation result not provided.") } } } /// Loads, instantiates and executes specified JavaScript module. /// /// This module will have "import.meta.main" equal to true. pub async fn execute_main_module( &mut self, id: ModuleId, ) -> Result<(), AnyError> { let mut receiver = self.js_runtime.mod_evaluate(id); tokio::select! { biased; maybe_result = &mut receiver => { debug!("received worker module evaluate {:#?}", maybe_result); // If `None` is returned it means that runtime was destroyed before // evaluation was complete. This can happen in Web Worker when `self.close()` // is called at top level. maybe_result.unwrap_or(Ok(())) } event_loop_result = self.run_event_loop(false) => { if self.internal_handle.is_terminated() { return Ok(()); } event_loop_result?; let maybe_result = receiver.await; maybe_result.unwrap_or(Ok(())) } } } fn poll_event_loop( &mut self, cx: &mut Context, wait_for_inspector: bool, ) -> Poll> { // If awakened because we are terminating, just return Ok if self.internal_handle.terminate_if_needed() { return Poll::Ready(Ok(())); } self.internal_handle.terminate_waker.register(cx.waker()); match self.js_runtime.poll_event_loop(cx, wait_for_inspector) { Poll::Ready(r) => { // If js ended because we are terminating, just return Ok if self.internal_handle.terminate_if_needed() { return Poll::Ready(Ok(())); } if let Err(e) = r { return Poll::Ready(Err(e)); } panic!( "coding error: either js is polling or the worker is terminated" ); } Poll::Pending => Poll::Pending, } } pub async fn run_event_loop( &mut self, wait_for_inspector: bool, ) -> Result<(), AnyError> { poll_fn(|cx| self.poll_event_loop(cx, wait_for_inspector)).await } // Starts polling for messages from worker host from JavaScript. fn start_polling_for_messages(&mut self) { let poll_for_messages_fn = self.poll_for_messages_fn.take().unwrap(); let scope = &mut self.js_runtime.handle_scope(); let poll_for_messages = v8::Local::::new(scope, poll_for_messages_fn); let fn_ = v8::Local::::try_from(poll_for_messages).unwrap(); let undefined = v8::undefined(scope); // This call may return `None` if worker is terminated. fn_.call(scope, undefined.into(), &[]); } } fn print_worker_error( error: &AnyError, name: &str, format_js_error_fn: Option<&FormatJsErrorFn>, ) { let error_str = match format_js_error_fn { Some(format_js_error_fn) => match error.downcast_ref::() { Some(js_error) => format_js_error_fn(js_error), None => error.to_string(), }, None => error.to_string(), }; eprintln!( "{}: Uncaught (in worker \"{}\") {}", colors::red_bold("error"), name, error_str.trim_start_matches("Uncaught "), ); } /// This function should be called from a thread dedicated to this worker. // TODO(bartlomieju): check if order of actions is aligned to Worker spec pub fn run_web_worker( worker: WebWorker, specifier: ModuleSpecifier, maybe_source_code: Option, preload_module_cb: Arc, pre_execute_module_cb: Arc, format_js_error_fn: Option>, ) -> Result<(), AnyError> { let name = worker.name.to_string(); // TODO(bartlomieju): run following block using "select!" // with terminate let fut = async move { let internal_handle = worker.internal_handle.clone(); let result = (preload_module_cb)(worker).await; let mut worker = match result { Ok(worker) => worker, Err(e) => { print_worker_error(&e, &name, format_js_error_fn.as_deref()); internal_handle .post_event(WorkerControlEvent::TerminalError(e)) .expect("Failed to post message to host"); // Failure to execute script is a terminal error, bye, bye. return Ok(()); } }; // Execute provided source code immediately let result = if let Some(source_code) = maybe_source_code { let r = worker.execute_script(&located_script_name!(), &source_code); worker.start_polling_for_messages(); r } else { // TODO(bartlomieju): add "type": "classic", ie. ability to load // script instead of module match worker.preload_main_module(&specifier).await { Ok(id) => { worker = match (pre_execute_module_cb)(worker).await { Ok(worker) => worker, Err(e) => { print_worker_error(&e, &name, format_js_error_fn.as_deref()); internal_handle .post_event(WorkerControlEvent::TerminalError(e)) .expect("Failed to post message to host"); // Failure to execute script is a terminal error, bye, bye. return Ok(()); } }; worker.start_polling_for_messages(); worker.execute_main_module(id).await } Err(e) => Err(e), } }; // If sender is closed it means that worker has already been closed from // within using "globalThis.close()" if internal_handle.is_terminated() { return Ok(()); } let result = if result.is_ok() { worker.run_event_loop(true).await } else { result }; if let Err(e) = result { print_worker_error(&e, &name, format_js_error_fn.as_deref()); internal_handle .post_event(WorkerControlEvent::TerminalError(e)) .expect("Failed to post message to host"); // Failure to execute script is a terminal error, bye, bye. return Ok(()); } debug!("Worker thread shuts down {}", &name); result }; run_local(fut) }