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denoland-deno/runtime/worker.rs

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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
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use std::pin::Pin;
use std::rc::Rc;
use std::sync::atomic::AtomicI32;
use std::sync::atomic::Ordering::Relaxed;
use std::sync::Arc;
use std::task::Context;
use std::task::Poll;
use deno_broadcast_channel::InMemoryBroadcastChannel;
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use deno_cache::CreateCache;
use deno_cache::SqliteBackedCache;
use deno_core::error::AnyError;
use deno_core::error::JsError;
refactor: Rewrite Inspector implementation (#10725) This commit refactors implementation of inspector. The intention is to be able to move inspector implementation to "deno_core". Following things were done to make that possible: * "runtime/inspector.rs" was split into "runtime/inspector/mod.rs" and "runtime/inspector/server.rs", separating inspector implementation from Websocket server implementation. * "DenoInspector" was renamed to "JsRuntimeInspector" and reference to "server" was removed from the structure, making it independent of Websocket server used to connect to Chrome Devtools. * "WebsocketSession" was renamed to "InspectorSession" and rewritten in such a way that it's not tied to Websockets anymore; instead it accepts a pair of "proxy" channel ends that allow to integrate the session with different "transports". * "InspectorSession" was renamed to "LocalInspectorSession" to better indicate that it's an "in-memory" session and doesn't require Websocket server. It was also rewritten in such a way that it uses "InspectorSession" from previous point instead of reimplementing "v8::inspector::ChannelImpl" trait; this is done by using the "proxy" channels to communicate with the V8 session. Consequently "LocalInspectorSession" is now a frontend to "InspectorSession". This introduces a small inconvenience that awaiting responses for "LocalInspectorSession" requires to concurrently poll worker's event loop. This arises from the fact that "InspectorSession" is now owned by "JsRuntimeInspector", which in turn is owned by "Worker" or "WebWorker". To ease this situation "Worker::with_event_loop" helper method was added, that takes a future and concurrently polls it along with the event loop (using "tokio::select!" macro inside a loop).
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use deno_core::futures::Future;
use deno_core::located_script_name;
use deno_core::v8;
use deno_core::CompiledWasmModuleStore;
use deno_core::Extension;
use deno_core::FsModuleLoader;
use deno_core::GetErrorClassFn;
use deno_core::JsRuntime;
use deno_core::LocalInspectorSession;
use deno_core::ModuleId;
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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::BlobStore;
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use log::debug;
use crate::inspector_server::InspectorServer;
use crate::js;
use crate::ops;
use crate::ops::io::Stdio;
use crate::permissions::PermissionsContainer;
use crate::BootstrapOptions;
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pub type FormatJsErrorFn = dyn Fn(&JsError) -> String + Sync + Send;
#[derive(Clone, Default)]
pub struct ExitCode(Arc<AtomicI32>);
impl ExitCode {
pub fn get(&self) -> i32 {
self.0.load(Relaxed)
}
pub fn set(&mut self, code: i32) {
self.0.store(code, Relaxed);
}
}
/// This worker is created and used by almost all
/// subcommands in Deno executable.
///
/// It provides ops available in the `Deno` namespace.
///
/// All `WebWorker`s created during program execution
/// are descendants of this worker.
pub struct MainWorker {
pub js_runtime: JsRuntime,
should_break_on_first_statement: bool,
should_wait_for_inspector_session: bool,
exit_code: ExitCode,
}
pub struct WorkerOptions {
pub bootstrap: BootstrapOptions,
/// JsRuntime extensions, not to be confused with ES modules.
/// Only ops registered by extensions will be initialized. If you need
/// to execute JS code from extensions, use `extensions_with_js` options
/// instead.
pub extensions: Vec<Extension>,
/// JsRuntime extensions, not to be confused with ES modules.
/// Ops registered by extensions will be initialized and JS code will be
/// executed. If you don't need to execute JS code from extensions, use
/// `extensions` option instead.
///
/// This is useful when creating snapshots, in such case you would pass
/// extensions using `extensions_with_js`, later when creating a runtime
/// from the snapshot, you would pass these extensions using `extensions`
/// option.
pub extensions_with_js: Vec<Extension>,
/// V8 snapshot that should be loaded on startup.
pub startup_snapshot: Option<Snapshot>,
pub unsafely_ignore_certificate_errors: Option<Vec<String>>,
pub root_cert_store: Option<RootCertStore>,
pub seed: Option<u64>,
/// Implementation of `ModuleLoader` which will be
/// called when V8 requests to load ES modules.
///
/// If not provided runtime will error if code being
/// executed tries to load modules.
pub module_loader: Rc<dyn ModuleLoader>,
pub npm_resolver: Option<Rc<dyn RequireNpmResolver>>,
// Callbacks invoked when creating new instance of WebWorker
pub create_web_worker_cb: Arc<ops::worker_host::CreateWebWorkerCb>,
pub web_worker_preload_module_cb: Arc<ops::worker_host::WorkerEventCb>,
pub web_worker_pre_execute_module_cb: Arc<ops::worker_host::WorkerEventCb>,
pub format_js_error_fn: Option<Arc<FormatJsErrorFn>>,
/// Source map reference for errors.
pub source_map_getter: Option<Box<dyn SourceMapGetter>>,
pub maybe_inspector_server: Option<Arc<InspectorServer>>,
// If true, the worker will wait for inspector session and break on first
// statement of user code. Takes higher precedence than
// `should_wait_for_inspector_session`.
pub should_break_on_first_statement: bool,
// If true, the worker will wait for inspector session before executing
// user code.
pub should_wait_for_inspector_session: bool,
/// Allows to map error type to a string "class" used to represent
/// error in JavaScript.
pub get_error_class_fn: Option<GetErrorClassFn>,
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pub cache_storage_dir: Option<std::path::PathBuf>,
pub origin_storage_dir: Option<std::path::PathBuf>,
pub blob_store: BlobStore,
pub broadcast_channel: InMemoryBroadcastChannel,
/// The store to use for transferring SharedArrayBuffers between isolates.
/// If multiple isolates should have the possibility of sharing
/// SharedArrayBuffers, they should use the same [SharedArrayBufferStore]. If
/// no [SharedArrayBufferStore] is specified, SharedArrayBuffer can not be
/// serialized.
pub shared_array_buffer_store: Option<SharedArrayBufferStore>,
/// The store to use for transferring `WebAssembly.Module` objects between
/// isolates.
/// If multiple isolates should have the possibility of sharing
/// `WebAssembly.Module` objects, they should use the same
/// [CompiledWasmModuleStore]. If no [CompiledWasmModuleStore] is specified,
/// `WebAssembly.Module` objects cannot be serialized.
pub compiled_wasm_module_store: Option<CompiledWasmModuleStore>,
pub stdio: Stdio,
}
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impl Default for WorkerOptions {
fn default() -> Self {
Self {
web_worker_preload_module_cb: Arc::new(|_| {
unimplemented!("web workers are not supported")
}),
web_worker_pre_execute_module_cb: Arc::new(|_| {
unimplemented!("web workers are not supported")
}),
create_web_worker_cb: Arc::new(|_| {
unimplemented!("web workers are not supported")
}),
module_loader: Rc::new(FsModuleLoader),
seed: None,
unsafely_ignore_certificate_errors: Default::default(),
should_break_on_first_statement: Default::default(),
should_wait_for_inspector_session: Default::default(),
compiled_wasm_module_store: Default::default(),
shared_array_buffer_store: Default::default(),
maybe_inspector_server: Default::default(),
format_js_error_fn: Default::default(),
get_error_class_fn: Default::default(),
origin_storage_dir: Default::default(),
cache_storage_dir: Default::default(),
broadcast_channel: Default::default(),
source_map_getter: Default::default(),
root_cert_store: Default::default(),
npm_resolver: Default::default(),
blob_store: Default::default(),
extensions: Default::default(),
extensions_with_js: Default::default(),
startup_snapshot: Default::default(),
bootstrap: Default::default(),
stdio: Default::default(),
}
}
}
impl MainWorker {
pub fn bootstrap_from_options(
main_module: ModuleSpecifier,
permissions: PermissionsContainer,
options: WorkerOptions,
) -> Self {
let bootstrap_options = options.bootstrap.clone();
let mut worker = Self::from_options(main_module, permissions, options);
worker.bootstrap(&bootstrap_options);
worker
}
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pub fn from_options(
main_module: ModuleSpecifier,
permissions: PermissionsContainer,
mut options: WorkerOptions,
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) -> Self {
// 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_worker")
.state(move |state| {
state.put::<PermissionsContainer>(permissions.clone());
state.put(ops::UnstableChecker { unstable });
state.put(ops::TestingFeaturesEnabled(enable_testing_features));
Ok(())
})
.build();
let exit_code = ExitCode(Arc::new(AtomicI32::new(0)));
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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))
});
// Internal modules
let mut extensions: Vec<Extension> = vec![
// Web APIs
deno_webidl::init(),
deno_console::init(),
deno_url::init(),
deno_web::init::<PermissionsContainer>(
options.blob_store.clone(),
options.bootstrap.location.clone(),
),
deno_fetch::init::<PermissionsContainer>(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()
}),
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deno_cache::init::<SqliteBackedCache>(create_cache),
deno_websocket::init::<PermissionsContainer>(
options.bootstrap.user_agent.clone(),
options.root_cert_store.clone(),
options.unsafely_ignore_certificate_errors.clone(),
),
deno_webstorage::init(options.origin_storage_dir.clone()),
deno_broadcast_channel::init(options.broadcast_channel.clone(), unstable),
deno_crypto::init(options.seed),
// ffi
deno_ffi::init::<PermissionsContainer>(unstable),
// Runtime ops
ops::runtime::init(main_module.clone()),
ops::worker_host::init(
options.create_web_worker_cb.clone(),
options.web_worker_preload_module_cb.clone(),
options.web_worker_pre_execute_module_cb.clone(),
options.format_js_error_fn.clone(),
),
ops::spawn::init(),
ops::fs_events::init(),
ops::fs::init(),
ops::io::init(),
ops::io::init_stdio(options.stdio),
deno_tls::init(),
deno_net::init::<PermissionsContainer>(
options.root_cert_store.clone(),
unstable,
options.unsafely_ignore_certificate_errors.clone(),
),
deno_napi::init::<PermissionsContainer>(),
deno_node::init_polyfill(),
deno_node::init::<PermissionsContainer>(options.npm_resolver),
ops::os::init(exit_code.clone()),
ops::permissions::init(),
ops::process::init(),
ops::signal::init(),
ops::tty::init(),
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deno_http::init(),
deno_flash::init::<PermissionsContainer>(unstable),
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ops::http::init(),
// Permissions ext (worker specific state)
perm_ext,
];
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,
extensions_with_js: options.extensions_with_js,
inspector: options.maybe_inspector_server.is_some(),
is_main: true,
..Default::default()
});
if let Some(server) = options.maybe_inspector_server.clone() {
server.register_inspector(
main_module.to_string(),
&mut js_runtime,
options.should_break_on_first_statement
|| options.should_wait_for_inspector_session,
);
// 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);
}
Self {
js_runtime,
should_break_on_first_statement: options.should_break_on_first_statement,
should_wait_for_inspector_session: options
.should_wait_for_inspector_session,
exit_code,
}
}
pub fn bootstrap(&mut self, options: &BootstrapOptions) {
let script = format!("bootstrap.mainRuntime({})", options.as_json());
self
.execute_script(&located_script_name!(), &script)
.expect("Failed to execute bootstrap script");
}
/// See [JsRuntime::execute_script](deno_core::JsRuntime::execute_script)
pub fn execute_script(
&mut self,
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script_name: &str,
source_code: &str,
) -> Result<v8::Global<v8::Value>, AnyError> {
self.js_runtime.execute_script(script_name, source_code)
}
/// Loads and instantiates specified JavaScript module as "main" module.
pub async fn preload_main_module(
&mut self,
module_specifier: &ModuleSpecifier,
) -> Result<ModuleId, AnyError> {
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<ModuleId, AnyError> {
self
.js_runtime
.load_side_module(module_specifier, None)
.await
}
/// Executes specified JavaScript module.
pub async fn evaluate_module(
&mut self,
id: ModuleId,
) -> Result<(), AnyError> {
self.wait_for_inspector_session();
let mut receiver = self.js_runtime.mod_evaluate(id);
tokio::select! {
// Not using biased mode leads to non-determinism for relatively simple
// programs.
biased;
maybe_result = &mut receiver => {
debug!("received module evaluate {:#?}", maybe_result);
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maybe_result.expect("Module evaluation result not provided.")
}
event_loop_result = self.run_event_loop(false) => {
event_loop_result?;
let maybe_result = receiver.await;
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maybe_result.expect("Module evaluation result not provided.")
}
}
}
/// Loads, instantiates and executes specified JavaScript module.
pub async fn execute_side_module(
&mut self,
module_specifier: &ModuleSpecifier,
) -> Result<(), AnyError> {
let id = self.preload_side_module(module_specifier).await?;
self.evaluate_module(id).await
}
/// 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,
module_specifier: &ModuleSpecifier,
) -> Result<(), AnyError> {
let id = self.preload_main_module(module_specifier).await?;
self.evaluate_module(id).await
}
fn wait_for_inspector_session(&mut self) {
if self.should_break_on_first_statement {
self
.js_runtime
.inspector()
.borrow_mut()
.wait_for_session_and_break_on_next_statement();
} else if self.should_wait_for_inspector_session {
self.js_runtime.inspector().borrow_mut().wait_for_session();
}
}
/// Create new inspector session. This function panics if Worker
/// was not configured to create inspector.
refactor: Rewrite Inspector implementation (#10725) This commit refactors implementation of inspector. The intention is to be able to move inspector implementation to "deno_core". Following things were done to make that possible: * "runtime/inspector.rs" was split into "runtime/inspector/mod.rs" and "runtime/inspector/server.rs", separating inspector implementation from Websocket server implementation. * "DenoInspector" was renamed to "JsRuntimeInspector" and reference to "server" was removed from the structure, making it independent of Websocket server used to connect to Chrome Devtools. * "WebsocketSession" was renamed to "InspectorSession" and rewritten in such a way that it's not tied to Websockets anymore; instead it accepts a pair of "proxy" channel ends that allow to integrate the session with different "transports". * "InspectorSession" was renamed to "LocalInspectorSession" to better indicate that it's an "in-memory" session and doesn't require Websocket server. It was also rewritten in such a way that it uses "InspectorSession" from previous point instead of reimplementing "v8::inspector::ChannelImpl" trait; this is done by using the "proxy" channels to communicate with the V8 session. Consequently "LocalInspectorSession" is now a frontend to "InspectorSession". This introduces a small inconvenience that awaiting responses for "LocalInspectorSession" requires to concurrently poll worker's event loop. This arises from the fact that "InspectorSession" is now owned by "JsRuntimeInspector", which in turn is owned by "Worker" or "WebWorker". To ease this situation "Worker::with_event_loop" helper method was added, that takes a future and concurrently polls it along with the event loop (using "tokio::select!" macro inside a loop).
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pub async fn create_inspector_session(&mut self) -> LocalInspectorSession {
self.js_runtime.maybe_init_inspector();
self.js_runtime.inspector().borrow().create_local_session()
}
pub fn poll_event_loop(
&mut self,
cx: &mut Context,
wait_for_inspector: bool,
) -> Poll<Result<(), AnyError>> {
self.js_runtime.poll_event_loop(cx, wait_for_inspector)
}
pub async fn run_event_loop(
&mut self,
wait_for_inspector: bool,
) -> Result<(), AnyError> {
self.js_runtime.run_event_loop(wait_for_inspector).await
}
refactor: Rewrite Inspector implementation (#10725) This commit refactors implementation of inspector. The intention is to be able to move inspector implementation to "deno_core". Following things were done to make that possible: * "runtime/inspector.rs" was split into "runtime/inspector/mod.rs" and "runtime/inspector/server.rs", separating inspector implementation from Websocket server implementation. * "DenoInspector" was renamed to "JsRuntimeInspector" and reference to "server" was removed from the structure, making it independent of Websocket server used to connect to Chrome Devtools. * "WebsocketSession" was renamed to "InspectorSession" and rewritten in such a way that it's not tied to Websockets anymore; instead it accepts a pair of "proxy" channel ends that allow to integrate the session with different "transports". * "InspectorSession" was renamed to "LocalInspectorSession" to better indicate that it's an "in-memory" session and doesn't require Websocket server. It was also rewritten in such a way that it uses "InspectorSession" from previous point instead of reimplementing "v8::inspector::ChannelImpl" trait; this is done by using the "proxy" channels to communicate with the V8 session. Consequently "LocalInspectorSession" is now a frontend to "InspectorSession". This introduces a small inconvenience that awaiting responses for "LocalInspectorSession" requires to concurrently poll worker's event loop. This arises from the fact that "InspectorSession" is now owned by "JsRuntimeInspector", which in turn is owned by "Worker" or "WebWorker". To ease this situation "Worker::with_event_loop" helper method was added, that takes a future and concurrently polls it along with the event loop (using "tokio::select!" macro inside a loop).
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/// A utility function that runs provided future concurrently with the event loop.
///
/// Useful when using a local inspector session.
pub async fn with_event_loop<'a, T>(
&mut self,
mut fut: Pin<Box<dyn Future<Output = T> + 'a>>,
) -> T {
loop {
tokio::select! {
biased;
refactor: Rewrite Inspector implementation (#10725) This commit refactors implementation of inspector. The intention is to be able to move inspector implementation to "deno_core". Following things were done to make that possible: * "runtime/inspector.rs" was split into "runtime/inspector/mod.rs" and "runtime/inspector/server.rs", separating inspector implementation from Websocket server implementation. * "DenoInspector" was renamed to "JsRuntimeInspector" and reference to "server" was removed from the structure, making it independent of Websocket server used to connect to Chrome Devtools. * "WebsocketSession" was renamed to "InspectorSession" and rewritten in such a way that it's not tied to Websockets anymore; instead it accepts a pair of "proxy" channel ends that allow to integrate the session with different "transports". * "InspectorSession" was renamed to "LocalInspectorSession" to better indicate that it's an "in-memory" session and doesn't require Websocket server. It was also rewritten in such a way that it uses "InspectorSession" from previous point instead of reimplementing "v8::inspector::ChannelImpl" trait; this is done by using the "proxy" channels to communicate with the V8 session. Consequently "LocalInspectorSession" is now a frontend to "InspectorSession". This introduces a small inconvenience that awaiting responses for "LocalInspectorSession" requires to concurrently poll worker's event loop. This arises from the fact that "InspectorSession" is now owned by "JsRuntimeInspector", which in turn is owned by "Worker" or "WebWorker". To ease this situation "Worker::with_event_loop" helper method was added, that takes a future and concurrently polls it along with the event loop (using "tokio::select!" macro inside a loop).
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result = &mut fut => {
return result;
}
_ = self.run_event_loop(false) => {}
refactor: Rewrite Inspector implementation (#10725) This commit refactors implementation of inspector. The intention is to be able to move inspector implementation to "deno_core". Following things were done to make that possible: * "runtime/inspector.rs" was split into "runtime/inspector/mod.rs" and "runtime/inspector/server.rs", separating inspector implementation from Websocket server implementation. * "DenoInspector" was renamed to "JsRuntimeInspector" and reference to "server" was removed from the structure, making it independent of Websocket server used to connect to Chrome Devtools. * "WebsocketSession" was renamed to "InspectorSession" and rewritten in such a way that it's not tied to Websockets anymore; instead it accepts a pair of "proxy" channel ends that allow to integrate the session with different "transports". * "InspectorSession" was renamed to "LocalInspectorSession" to better indicate that it's an "in-memory" session and doesn't require Websocket server. It was also rewritten in such a way that it uses "InspectorSession" from previous point instead of reimplementing "v8::inspector::ChannelImpl" trait; this is done by using the "proxy" channels to communicate with the V8 session. Consequently "LocalInspectorSession" is now a frontend to "InspectorSession". This introduces a small inconvenience that awaiting responses for "LocalInspectorSession" requires to concurrently poll worker's event loop. This arises from the fact that "InspectorSession" is now owned by "JsRuntimeInspector", which in turn is owned by "Worker" or "WebWorker". To ease this situation "Worker::with_event_loop" helper method was added, that takes a future and concurrently polls it along with the event loop (using "tokio::select!" macro inside a loop).
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};
}
}
/// Return exit code set by the executed code (either in main worker
/// or one of child web workers).
pub fn exit_code(&self) -> i32 {
self.exit_code.get()
}
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/// Dispatches "load" event to the JavaScript runtime.
///
/// Does not poll event loop, and thus not await any of the "load" event handlers.
pub fn dispatch_load_event(
&mut self,
script_name: &str,
) -> Result<(), AnyError> {
self.execute_script(
script_name,
// NOTE(@bartlomieju): not using `globalThis` here, because user might delete
// it. Instead we're using global `dispatchEvent` function which will
// used a saved reference to global scope.
"dispatchEvent(new Event('load'))",
)?;
Ok(())
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}
/// Dispatches "unload" event to the JavaScript runtime.
///
/// Does not poll event loop, and thus not await any of the "unload" event handlers.
pub fn dispatch_unload_event(
&mut self,
script_name: &str,
) -> Result<(), AnyError> {
self.execute_script(
script_name,
// NOTE(@bartlomieju): not using `globalThis` here, because user might delete
// it. Instead we're using global `dispatchEvent` function which will
// used a saved reference to global scope.
"dispatchEvent(new Event('unload'))",
)?;
Ok(())
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}
/// Dispatches "beforeunload" event to the JavaScript runtime. Returns a boolean
/// indicating if the event was prevented and thus event loop should continue
/// running.
pub fn dispatch_beforeunload_event(
&mut self,
script_name: &str,
) -> Result<bool, AnyError> {
let value = self.js_runtime.execute_script(
script_name,
// NOTE(@bartlomieju): not using `globalThis` here, because user might delete
// it. Instead we're using global `dispatchEvent` function which will
// used a saved reference to global scope.
"dispatchEvent(new Event('beforeunload', { cancelable: true }));",
)?;
let local_value = value.open(&mut self.js_runtime.handle_scope());
Ok(local_value.is_false())
}
}