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mod info;
mod loaders;
use crate::{
folder::LoadedFolder,
io::{
AssetReaderError, AssetSource, AssetSourceEvent, AssetSourceId, AssetSources,
ErasedAssetReader, MissingAssetSourceError, MissingProcessedAssetReaderError, Reader,
},
loader::{AssetLoader, ErasedAssetLoader, LoadContext, LoadedAsset},
meta::{
loader_settings_meta_transform, AssetActionMinimal, AssetMetaDyn, AssetMetaMinimal,
MetaTransform, Settings,
},
path::AssetPath,
Asset, AssetEvent, AssetHandleProvider, AssetId, AssetLoadFailedEvent, AssetMetaCheck, Assets,
DeserializeMetaError, ErasedLoadedAsset, Handle, LoadedUntypedAsset, UntypedAssetId,
UntypedAssetLoadFailedEvent, UntypedHandle,
};
use bevy_ecs::prelude::*;
use bevy_tasks::IoTaskPool;
use bevy_utils::tracing::{error, info};
use bevy_utils::{CowArc, HashSet};
use crossbeam_channel::{Receiver, Sender};
use futures_lite::StreamExt;
use info::*;
use loaders::*;
use parking_lot::RwLock;
use std::future::Future;
use std::{any::Any, path::PathBuf};
use std::{any::TypeId, path::Path, sync::Arc};
use thiserror::Error;
// Needed for doc string
#[allow(unused_imports)]
use crate::io::{AssetReader, AssetWriter};
/// Loads and tracks the state of [`Asset`] values from a configured [`AssetReader`]. This can be used to kick off new asset loads and
/// retrieve their current load states.
///
/// The general process to load an asset is:
/// 1. Initialize a new [`Asset`] type with the [`AssetServer`] via [`AssetApp::init_asset`], which will internally call [`AssetServer::register_asset`]
/// and set up related ECS [`Assets`] storage and systems.
/// 2. Register one or more [`AssetLoader`]s for that asset with [`AssetApp::init_asset_loader`]
/// 3. Add the asset to your asset folder (defaults to `assets`).
/// 4. Call [`AssetServer::load`] with a path to your asset.
///
/// [`AssetServer`] can be cloned. It is backed by an [`Arc`] so clones will share state. Clones can be freely used in parallel.
///
/// [`AssetApp::init_asset`]: crate::AssetApp::init_asset
/// [`AssetApp::init_asset_loader`]: crate::AssetApp::init_asset_loader
#[derive(Resource, Clone)]
pub struct AssetServer {
pub(crate) data: Arc<AssetServerData>,
}
/// Internal data used by [`AssetServer`]. This is intended to be used from within an [`Arc`].
pub(crate) struct AssetServerData {
pub(crate) infos: RwLock<AssetInfos>,
pub(crate) loaders: Arc<RwLock<AssetLoaders>>,
asset_event_sender: Sender<InternalAssetEvent>,
asset_event_receiver: Receiver<InternalAssetEvent>,
sources: AssetSources,
mode: AssetServerMode,
meta_check: AssetMetaCheck,
}
/// The "asset mode" the server is currently in.
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub enum AssetServerMode {
/// This server loads unprocessed assets.
Unprocessed,
/// This server loads processed assets.
Processed,
}
impl AssetServer {
/// Create a new instance of [`AssetServer`]. If `watch_for_changes` is true, the [`AssetReader`] storage will watch for changes to
/// asset sources and hot-reload them.
pub fn new(sources: AssetSources, mode: AssetServerMode, watching_for_changes: bool) -> Self {
Self::new_with_loaders(
sources,
Default::default(),
mode,
AssetMetaCheck::Always,
watching_for_changes,
)
}
/// Create a new instance of [`AssetServer`]. If `watch_for_changes` is true, the [`AssetReader`] storage will watch for changes to
/// asset sources and hot-reload them.
pub fn new_with_meta_check(
sources: AssetSources,
mode: AssetServerMode,
meta_check: AssetMetaCheck,
watching_for_changes: bool,
) -> Self {
Self::new_with_loaders(
sources,
Default::default(),
mode,
meta_check,
watching_for_changes,
)
}
pub(crate) fn new_with_loaders(
sources: AssetSources,
loaders: Arc<RwLock<AssetLoaders>>,
mode: AssetServerMode,
meta_check: AssetMetaCheck,
watching_for_changes: bool,
) -> Self {
let (asset_event_sender, asset_event_receiver) = crossbeam_channel::unbounded();
let mut infos = AssetInfos::default();
infos.watching_for_changes = watching_for_changes;
Self {
data: Arc::new(AssetServerData {
sources,
mode,
meta_check,
asset_event_sender,
asset_event_receiver,
loaders,
infos: RwLock::new(infos),
}),
}
}
/// Retrieves the [`AssetSource`] for the given `source`.
pub fn get_source<'a>(
&'a self,
source: impl Into<AssetSourceId<'a>>,
) -> Result<&'a AssetSource, MissingAssetSourceError> {
self.data.sources.get(source.into())
}
/// Returns true if the [`AssetServer`] watches for changes.
pub fn watching_for_changes(&self) -> bool {
self.data.infos.read().watching_for_changes
}
/// Registers a new [`AssetLoader`]. [`AssetLoader`]s must be registered before they can be used.
pub fn register_loader<L: AssetLoader>(&self, loader: L) {
self.data.loaders.write().push(loader);
}
/// Registers a new [`Asset`] type. [`Asset`] types must be registered before assets of that type can be loaded.
pub fn register_asset<A: Asset>(&self, assets: &Assets<A>) {
self.register_handle_provider(assets.get_handle_provider());
fn sender<A: Asset>(world: &mut World, id: UntypedAssetId) {
world
.resource_mut::<Events<AssetEvent<A>>>()
.send(AssetEvent::LoadedWithDependencies { id: id.typed() });
}
fn failed_sender<A: Asset>(
world: &mut World,
id: UntypedAssetId,
path: AssetPath<'static>,
error: AssetLoadError,
) {
world
.resource_mut::<Events<AssetLoadFailedEvent<A>>>()
.send(AssetLoadFailedEvent {
id: id.typed(),
path,
error,
});
}
let mut infos = self.data.infos.write();
infos
.dependency_loaded_event_sender
.insert(TypeId::of::<A>(), sender::<A>);
infos
.dependency_failed_event_sender
.insert(TypeId::of::<A>(), failed_sender::<A>);
}
pub(crate) fn register_handle_provider(&self, handle_provider: AssetHandleProvider) {
let mut infos = self.data.infos.write();
infos
.handle_providers
.insert(handle_provider.type_id, handle_provider);
}
/// Returns the registered [`AssetLoader`] associated with the given extension, if it exists.
pub async fn get_asset_loader_with_extension(
&self,
extension: &str,
) -> Result<Arc<dyn ErasedAssetLoader>, MissingAssetLoaderForExtensionError> {
let error = || MissingAssetLoaderForExtensionError {
extensions: vec![extension.to_string()],
};
let loader = { self.data.loaders.read().get_by_extension(extension) };
loader.ok_or_else(error)?.get().await.map_err(|_| error())
}
/// Returns the registered [`AssetLoader`] associated with the given [`std::any::type_name`], if it exists.
pub async fn get_asset_loader_with_type_name(
&self,
type_name: &str,
) -> Result<Arc<dyn ErasedAssetLoader>, MissingAssetLoaderForTypeNameError> {
let error = || MissingAssetLoaderForTypeNameError {
type_name: type_name.to_string(),
};
let loader = { self.data.loaders.read().get_by_name(type_name) };
loader.ok_or_else(error)?.get().await.map_err(|_| error())
}
/// Retrieves the default [`AssetLoader`] for the given path, if one can be found.
pub async fn get_path_asset_loader<'a>(
&self,
path: impl Into<AssetPath<'a>>,
) -> Result<Arc<dyn ErasedAssetLoader>, MissingAssetLoaderForExtensionError> {
let path = path.into();
let error = || {
let Some(full_extension) = path.get_full_extension() else {
return MissingAssetLoaderForExtensionError {
extensions: Vec::new(),
};
};
let mut extensions = vec![full_extension.clone()];
extensions.extend(
AssetPath::iter_secondary_extensions(&full_extension).map(|e| e.to_string()),
);
MissingAssetLoaderForExtensionError { extensions }
};
let loader = { self.data.loaders.read().get_by_path(&path) };
loader.ok_or_else(error)?.get().await.map_err(|_| error())
}
/// Retrieves the default [`AssetLoader`] for the given [`Asset`] [`TypeId`], if one can be found.
pub async fn get_asset_loader_with_asset_type_id<'a>(
&self,
type_id: TypeId,
) -> Result<Arc<dyn ErasedAssetLoader>, MissingAssetLoaderForTypeIdError> {
let error = || MissingAssetLoaderForTypeIdError { type_id };
let loader = { self.data.loaders.read().get_by_type(type_id) };
loader.ok_or_else(error)?.get().await.map_err(|_| error())
}
/// Retrieves the default [`AssetLoader`] for the given [`Asset`] type, if one can be found.
pub async fn get_asset_loader_with_asset_type<'a, A: Asset>(
&self,
) -> Result<Arc<dyn ErasedAssetLoader>, MissingAssetLoaderForTypeIdError> {
self.get_asset_loader_with_asset_type_id(TypeId::of::<A>())
.await
}
/// Begins loading an [`Asset`] of type `A` stored at `path`. This will not block on the asset load. Instead,
/// it returns a "strong" [`Handle`]. When the [`Asset`] is loaded (and enters [`LoadState::Loaded`]), it will be added to the
/// associated [`Assets`] resource.
///
/// In case the file path contains a hashtag (`#`), the `path` must be specified using [`Path`]
/// or [`AssetPath`] because otherwise the hashtag would be interpreted as separator between
/// the file path and the label. For example:
///
/// ```no_run
/// # use bevy_asset::{AssetServer, Handle, LoadedUntypedAsset};
/// # use bevy_ecs::prelude::Res;
/// # use std::path::Path;
/// // `#path` is a label.
/// # fn setup(asset_server: Res<AssetServer>) {
/// # let handle: Handle<LoadedUntypedAsset> =
/// asset_server.load("some/file#path");
///
/// // `#path` is part of the file name.
/// # let handle: Handle<LoadedUntypedAsset> =
/// asset_server.load(Path::new("some/file#path"));
/// # }
/// ```
///
/// Furthermore, if you need to load a file with a hashtag in its name _and_ a label, you can
/// manually construct an [`AssetPath`].
///
/// ```no_run
/// # use bevy_asset::{AssetPath, AssetServer, Handle, LoadedUntypedAsset};
/// # use bevy_ecs::prelude::Res;
/// # use std::path::Path;
/// # fn setup(asset_server: Res<AssetServer>) {
/// # let handle: Handle<LoadedUntypedAsset> =
/// asset_server.load(AssetPath::from_path(Path::new("some/file#path")).with_label("subasset"));
/// # }
/// ```
///
/// You can check the asset's load state by reading [`AssetEvent`] events, calling [`AssetServer::load_state`], or checking
/// the [`Assets`] storage to see if the [`Asset`] exists yet.
///
/// The asset load will fail and an error will be printed to the logs if the asset stored at `path` is not of type `A`.
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub fn load<'a, A: Asset>(&self, path: impl Into<AssetPath<'a>>) -> Handle<A> {
self.load_with_meta_transform(path, None, ())
}
/// Begins loading an [`Asset`] of type `A` stored at `path` while holding a guard item.
/// The guard item is dropped when either the asset is loaded or loading has failed.
///
/// This function returns a "strong" [`Handle`]. When the [`Asset`] is loaded (and enters [`LoadState::Loaded`]), it will be added to the
/// associated [`Assets`] resource.
///
/// The guard item should notify the caller in its [`Drop`] implementation. See example `multi_asset_sync`.
/// Synchronously this can be a [`Arc<AtomicU32>`] that decrements its counter, asynchronously this can be a `Barrier`.
/// This function only guarantees the asset referenced by the [`Handle`] is loaded. If your asset is separated into
/// multiple files, sub-assets referenced by the main asset might still be loading, depend on the implementation of the [`AssetLoader`].
///
/// Additionally, you can check the asset's load state by reading [`AssetEvent`] events, calling [`AssetServer::load_state`], or checking
/// the [`Assets`] storage to see if the [`Asset`] exists yet.
///
/// The asset load will fail and an error will be printed to the logs if the asset stored at `path` is not of type `A`.
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub fn load_acquire<'a, A: Asset, G: Send + Sync + 'static>(
&self,
path: impl Into<AssetPath<'a>>,
guard: G,
) -> Handle<A> {
self.load_with_meta_transform(path, None, guard)
}
/// Begins loading an [`Asset`] of type `A` stored at `path`. The given `settings` function will override the asset's
/// [`AssetLoader`] settings. The type `S` _must_ match the configured [`AssetLoader::Settings`] or `settings` changes
/// will be ignored and an error will be printed to the log.
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub fn load_with_settings<'a, A: Asset, S: Settings>(
&self,
path: impl Into<AssetPath<'a>>,
settings: impl Fn(&mut S) + Send + Sync + 'static,
) -> Handle<A> {
self.load_with_meta_transform(path, Some(loader_settings_meta_transform(settings)), ())
}
/// Begins loading an [`Asset`] of type `A` stored at `path` while holding a guard item.
/// The guard item is dropped when either the asset is loaded or loading has failed.
///
/// This function only guarantees the asset referenced by the [`Handle`] is loaded. If your asset is separated into
/// multiple files, sub-assets referenced by the main asset might still be loading, depend on the implementation of the [`AssetLoader`].
///
/// The given `settings` function will override the asset's
/// [`AssetLoader`] settings. The type `S` _must_ match the configured [`AssetLoader::Settings`] or `settings` changes
/// will be ignored and an error will be printed to the log.
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub fn load_acquire_with_settings<'a, A: Asset, S: Settings, G: Send + Sync + 'static>(
&self,
path: impl Into<AssetPath<'a>>,
settings: impl Fn(&mut S) + Send + Sync + 'static,
guard: G,
) -> Handle<A> {
self.load_with_meta_transform(path, Some(loader_settings_meta_transform(settings)), guard)
}
pub(crate) fn load_with_meta_transform<'a, A: Asset, G: Send + Sync + 'static>(
&self,
path: impl Into<AssetPath<'a>>,
meta_transform: Option<MetaTransform>,
guard: G,
) -> Handle<A> {
let path = path.into().into_owned();
let (handle, should_load) = self.data.infos.write().get_or_create_path_handle::<A>(
path.clone(),
HandleLoadingMode::Request,
meta_transform,
);
if should_load {
let owned_handle = Some(handle.clone().untyped());
let server = self.clone();
IoTaskPool::get()
.spawn(async move {
if let Err(err) = server.load_internal(owned_handle, path, false, None).await {
error!("{}", err);
}
drop(guard);
})
.detach();
}
handle
}
/// Asynchronously load an asset that you do not know the type of statically. If you _do_ know the type of the asset,
/// you should use [`AssetServer::load`]. If you don't know the type of the asset, but you can't use an async method,
/// consider using [`AssetServer::load_untyped`].
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub async fn load_untyped_async<'a>(
&self,
path: impl Into<AssetPath<'a>>,
) -> Result<UntypedHandle, AssetLoadError> {
let path: AssetPath = path.into();
self.load_internal(None, path, false, None).await
}
pub(crate) fn load_untyped_with_meta_transform<'a>(
&self,
path: impl Into<AssetPath<'a>>,
meta_transform: Option<MetaTransform>,
) -> Handle<LoadedUntypedAsset> {
let path = path.into().into_owned();
let untyped_source = AssetSourceId::Name(match path.source() {
AssetSourceId::Default => CowArc::Borrowed(UNTYPED_SOURCE_SUFFIX),
AssetSourceId::Name(source) => {
CowArc::Owned(format!("{source}--{UNTYPED_SOURCE_SUFFIX}").into())
}
});
let (handle, should_load) = self
.data
.infos
.write()
.get_or_create_path_handle::<LoadedUntypedAsset>(
path.clone().with_source(untyped_source),
HandleLoadingMode::Request,
meta_transform,
);
if !should_load {
return handle;
}
let id = handle.id().untyped();
let server = self.clone();
IoTaskPool::get()
.spawn(async move {
let path_clone = path.clone();
match server.load_untyped_async(path).await {
Ok(handle) => server.send_asset_event(InternalAssetEvent::Loaded {
id,
loaded_asset: LoadedAsset::new_with_dependencies(
LoadedUntypedAsset { handle },
None,
)
.into(),
}),
Err(err) => {
error!("{err}");
server.send_asset_event(InternalAssetEvent::Failed {
id,
path: path_clone,
error: err,
});
}
}
})
.detach();
handle
}
/// Load an asset without knowing its type. The method returns a handle to a [`LoadedUntypedAsset`].
///
/// Once the [`LoadedUntypedAsset`] is loaded, an untyped handle for the requested path can be
/// retrieved from it.
///
/// ```
/// use bevy_asset::{Assets, Handle, LoadedUntypedAsset};
/// use bevy_ecs::system::{Res, Resource};
///
/// #[derive(Resource)]
/// struct LoadingUntypedHandle(Handle<LoadedUntypedAsset>);
///
/// fn resolve_loaded_untyped_handle(loading_handle: Res<LoadingUntypedHandle>, loaded_untyped_assets: Res<Assets<LoadedUntypedAsset>>) {
/// if let Some(loaded_untyped_asset) = loaded_untyped_assets.get(&loading_handle.0) {
/// let handle = loaded_untyped_asset.handle.clone();
/// // continue working with `handle` which points to the asset at the originally requested path
/// }
/// }
/// ```
///
/// This indirection enables a non blocking load of an untyped asset, since I/O is
/// required to figure out the asset type before a handle can be created.
#[must_use = "not using the returned strong handle may result in the unexpected release of the assets"]
pub fn load_untyped<'a>(&self, path: impl Into<AssetPath<'a>>) -> Handle<LoadedUntypedAsset> {
self.load_untyped_with_meta_transform(path, None)
}
/// Performs an async asset load.
///
/// `input_handle` must only be [`Some`] if `should_load` was true when retrieving `input_handle`. This is an optimization to
/// avoid looking up `should_load` twice, but it means you _must_ be sure a load is necessary when calling this function with [`Some`].
async fn load_internal<'a>(
&self,
input_handle: Option<UntypedHandle>,
path: AssetPath<'a>,
force: bool,
meta_transform: Option<MetaTransform>,
) -> Result<UntypedHandle, AssetLoadError> {
let asset_type_id = input_handle.as_ref().map(|handle| handle.type_id());
let path = path.into_owned();
let path_clone = path.clone();
let (mut meta, loader, mut reader) = self
.get_meta_loader_and_reader(&path_clone, asset_type_id)
.await
.map_err(|e| {
// if there was an input handle, a "load" operation has already started, so we must produce a "failure" event, if
// we cannot find the meta and loader
if let Some(handle) = &input_handle {
self.send_asset_event(InternalAssetEvent::Failed {
id: handle.id(),
path: path.clone_owned(),
error: e.clone(),
});
}
e
})?;
// This contains Some(UntypedHandle), if it was retrievable
// If it is None, that is because it was _not_ retrievable, due to
// 1. The handle was not already passed in for this path, meaning we can't just use that
// 2. The asset has not been loaded yet, meaning there is no existing Handle for it
// 3. The path has a label, meaning the AssetLoader's root asset type is not the path's asset type
//
// In the None case, the only course of action is to wait for the asset to load so we can allocate the
// handle for that type.
//
// TODO: Note that in the None case, multiple asset loads for the same path can happen at the same time
// (rather than "early out-ing" in the "normal" case)
// This would be resolved by a universal asset id, as we would not need to resolve the asset type
// to generate the ID. See this issue: https://github.com/bevyengine/bevy/issues/10549
let handle_result = match input_handle {
Some(handle) => {
// if a handle was passed in, the "should load" check was already done
Some((handle, true))
}
None => {
let mut infos = self.data.infos.write();
let result = infos.get_or_create_path_handle_internal(
path.clone(),
path.label().is_none().then(|| loader.asset_type_id()),
HandleLoadingMode::Request,
meta_transform,
);
unwrap_with_context(result, loader.asset_type_name())
}
};
let handle = if let Some((handle, should_load)) = handle_result {
if path.label().is_none() && handle.type_id() != loader.asset_type_id() {
error!(
"Expected {:?}, got {:?}",
handle.type_id(),
loader.asset_type_id()
);
return Err(AssetLoadError::RequestedHandleTypeMismatch {
path: path.into_owned(),
requested: handle.type_id(),
actual_asset_name: loader.asset_type_name(),
loader_name: loader.type_name(),
});
}
if !should_load && !force {
return Ok(handle);
}
Some(handle)
} else {
None
};
// if the handle result is None, we definitely need to load the asset
let (base_handle, base_path) = if path.label().is_some() {
let mut infos = self.data.infos.write();
let base_path = path.without_label().into_owned();
let (base_handle, _) = infos.get_or_create_path_handle_untyped(
base_path.clone(),
loader.asset_type_id(),
loader.asset_type_name(),
HandleLoadingMode::Force,
None,
);
(base_handle, base_path)
} else {
(handle.clone().unwrap(), path.clone())
};
if let Some(meta_transform) = base_handle.meta_transform() {
(*meta_transform)(&mut *meta);
}
match self
.load_with_meta_loader_and_reader(&base_path, meta, &*loader, &mut *reader, true, false)
.await
{
Ok(loaded_asset) => {
let final_handle = if let Some(label) = path.label_cow() {
match loaded_asset.labeled_assets.get(&label) {
Some(labeled_asset) => labeled_asset.handle.clone(),
None => {
let mut all_labels: Vec<String> = loaded_asset
.labeled_assets
.keys()
.map(|s| (**s).to_owned())
.collect();
all_labels.sort_unstable();
return Err(AssetLoadError::MissingLabel {
base_path,
label: label.to_string(),
all_labels,
});
}
}
} else {
// if the path does not have a label, the handle must exist at this point
handle.unwrap()
};
self.send_loaded_asset(base_handle.id(), loaded_asset);
Ok(final_handle)
}
Err(err) => {
self.send_asset_event(InternalAssetEvent::Failed {
id: base_handle.id(),
error: err.clone(),
path: path.into_owned(),
});
Err(err)
}
}
}
/// Sends a load event for the given `loaded_asset` and does the same recursively for all
/// labeled assets.
fn send_loaded_asset(&self, id: UntypedAssetId, mut loaded_asset: ErasedLoadedAsset) {
for (_, labeled_asset) in loaded_asset.labeled_assets.drain() {
self.send_loaded_asset(labeled_asset.handle.id(), labeled_asset.asset);
}
self.send_asset_event(InternalAssetEvent::Loaded { id, loaded_asset });
}
/// Kicks off a reload of the asset stored at the given path. This will only reload the asset if it currently loaded.
pub fn reload<'a>(&self, path: impl Into<AssetPath<'a>>) {
let server = self.clone();
let path = path.into().into_owned();
IoTaskPool::get()
.spawn(async move {
let mut reloaded = false;
let requests = server
.data
.infos
.read()
.get_path_handles(&path)
.map(|handle| server.load_internal(Some(handle), path.clone(), true, None))
.collect::<Vec<_>>();
for result in requests {
match result.await {
Ok(_) => reloaded = true,
Err(err) => error!("{}", err),
}
}
if !reloaded && server.data.infos.read().should_reload(&path) {
if let Err(err) = server.load_internal(None, path, true, None).await {
error!("{}", err);
}
}
})
.detach();
}
/// Queues a new asset to be tracked by the [`AssetServer`] and returns a [`Handle`] to it. This can be used to track
/// dependencies of assets created at runtime.
///
/// After the asset has been fully loaded by the [`AssetServer`], it will show up in the relevant [`Assets`] storage.
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub fn add<A: Asset>(&self, asset: A) -> Handle<A> {
self.load_asset(LoadedAsset::new_with_dependencies(asset, None))
}
pub(crate) fn load_asset<A: Asset>(&self, asset: impl Into<LoadedAsset<A>>) -> Handle<A> {
let loaded_asset: LoadedAsset<A> = asset.into();
let erased_loaded_asset: ErasedLoadedAsset = loaded_asset.into();
self.load_asset_untyped(None, erased_loaded_asset)
.typed_debug_checked()
}
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub(crate) fn load_asset_untyped(
&self,
path: Option<AssetPath<'static>>,
asset: impl Into<ErasedLoadedAsset>,
) -> UntypedHandle {
let loaded_asset = asset.into();
let handle = if let Some(path) = path {
let (handle, _) = self.data.infos.write().get_or_create_path_handle_untyped(
path,
loaded_asset.asset_type_id(),
loaded_asset.asset_type_name(),
HandleLoadingMode::NotLoading,
None,
);
handle
} else {
self.data.infos.write().create_loading_handle_untyped(
loaded_asset.asset_type_id(),
loaded_asset.asset_type_name(),
)
};
self.send_asset_event(InternalAssetEvent::Loaded {
id: handle.id(),
loaded_asset,
});
handle
}
/// Queues a new asset to be tracked by the [`AssetServer`] and returns a [`Handle`] to it. This can be used to track
/// dependencies of assets created at runtime.
///
/// After the asset has been fully loaded, it will show up in the relevant [`Assets`] storage.
#[must_use = "not using the returned strong handle may result in the unexpected release of the asset"]
pub fn add_async<A: Asset, E: std::error::Error + Send + Sync + 'static>(
&self,
future: impl Future<Output = Result<A, E>> + Send + 'static,
) -> Handle<A> {
let handle = self
.data
.infos
.write()
.create_loading_handle_untyped(std::any::TypeId::of::<A>(), std::any::type_name::<A>());
let id = handle.id();
let event_sender = self.data.asset_event_sender.clone();
IoTaskPool::get()
.spawn(async move {
match future.await {
Ok(asset) => {
let loaded_asset = LoadedAsset::new_with_dependencies(asset, None).into();
event_sender
.send(InternalAssetEvent::Loaded { id, loaded_asset })
.unwrap();
}
Err(error) => {
let error = AddAsyncError {
error: Arc::new(error),
};
error!("{error}");
event_sender
.send(InternalAssetEvent::Failed {
id,
path: Default::default(),
error: AssetLoadError::AddAsyncError(error),
})
.unwrap();
}
}
})
.detach();
handle.typed_debug_checked()
}
/// Loads all assets from the specified folder recursively. The [`LoadedFolder`] asset (when it loads) will
/// contain handles to all assets in the folder. You can wait for all assets to load by checking the [`LoadedFolder`]'s
/// [`RecursiveDependencyLoadState`].
///
/// Loading the same folder multiple times will return the same handle. If the `file_watcher`
/// feature is enabled, [`LoadedFolder`] handles will reload when a file in the folder is
/// removed, added or moved. This includes files in subdirectories and moving, adding,
/// or removing complete subdirectories.
#[must_use = "not using the returned strong handle may result in the unexpected release of the assets"]
pub fn load_folder<'a>(&self, path: impl Into<AssetPath<'a>>) -> Handle<LoadedFolder> {
let path = path.into().into_owned();
let (handle, should_load) = self
.data
.infos
.write()
.get_or_create_path_handle::<LoadedFolder>(
path.clone(),
HandleLoadingMode::Request,
None,
);
if !should_load {
return handle;
}
let id = handle.id().untyped();
self.load_folder_internal(id, path);
handle
}
pub(crate) fn load_folder_internal(&self, id: UntypedAssetId, path: AssetPath) {
async fn load_folder<'a>(
source: AssetSourceId<'static>,
path: &'a Path,
reader: &'a dyn ErasedAssetReader,
server: &'a AssetServer,
handles: &'a mut Vec<UntypedHandle>,
) -> Result<(), AssetLoadError> {
let is_dir = reader.is_directory(path).await?;
if is_dir {
let mut path_stream = reader.read_directory(path.as_ref()).await?;
while let Some(child_path) = path_stream.next().await {
if reader.is_directory(&child_path).await? {
Box::pin(load_folder(
source.clone(),
&child_path,
reader,
server,
handles,
))
.await?;
} else {
let path = child_path.to_str().expect("Path should be a valid string.");
let asset_path = AssetPath::parse(path).with_source(source.clone());
match server.load_untyped_async(asset_path).await {
Ok(handle) => handles.push(handle),
// skip assets that cannot be loaded
Err(
AssetLoadError::MissingAssetLoaderForTypeName(_)
| AssetLoadError::MissingAssetLoaderForExtension(_),
) => {}
Err(err) => return Err(err),
}
}
}
}
Ok(())
}
let path = path.into_owned();
let server = self.clone();
IoTaskPool::get()
.spawn(async move {
let Ok(source) = server.get_source(path.source()) else {
error!(
"Failed to load {path}. AssetSource {:?} does not exist",
path.source()
);
return;
};
let asset_reader = match server.data.mode {
AssetServerMode::Unprocessed { .. } => source.reader(),
AssetServerMode::Processed { .. } => match source.processed_reader() {
Ok(reader) => reader,
Err(_) => {
error!(
"Failed to load {path}. AssetSource {:?} does not have a processed AssetReader",
path.source()
);
return;
}
},
};
let mut handles = Vec::new();
match load_folder(source.id(), path.path(), asset_reader, &server, &mut handles).await {
Ok(_) => server.send_asset_event(InternalAssetEvent::Loaded {
id,
loaded_asset: LoadedAsset::new_with_dependencies(
LoadedFolder { handles },
None,
)
.into(),
}),
Err(err) => {
error!("Failed to load folder. {err}");
server.send_asset_event(InternalAssetEvent::Failed { id, error: err, path });
},
}
})
.detach();
}
fn send_asset_event(&self, event: InternalAssetEvent) {
self.data.asset_event_sender.send(event).unwrap();
}
/// Retrieves all loads states for the given asset id.
pub fn get_load_states(
&self,
id: impl Into<UntypedAssetId>,
) -> Option<(LoadState, DependencyLoadState, RecursiveDependencyLoadState)> {
self.data
.infos
.read()
.get(id.into())
.map(|i| (i.load_state.clone(), i.dep_load_state, i.rec_dep_load_state))
}
/// Retrieves the main [`LoadState`] of a given asset `id`.
///
/// Note that this is "just" the root asset load state. To check if an asset _and_ its recursive
/// dependencies have loaded, see [`AssetServer::is_loaded_with_dependencies`].
pub fn get_load_state(&self, id: impl Into<UntypedAssetId>) -> Option<LoadState> {
self.data
.infos
.read()
.get(id.into())
.map(|i| i.load_state.clone())
}
/// Retrieves the [`RecursiveDependencyLoadState`] of a given asset `id`.
pub fn get_recursive_dependency_load_state(
&self,
id: impl Into<UntypedAssetId>,
) -> Option<RecursiveDependencyLoadState> {
self.data
.infos
.read()
.get(id.into())
.map(|i| i.rec_dep_load_state)
}
/// Retrieves the main [`LoadState`] of a given asset `id`.
pub fn load_state(&self, id: impl Into<UntypedAssetId>) -> LoadState {
self.get_load_state(id).unwrap_or(LoadState::NotLoaded)
}
/// Retrieves the [`RecursiveDependencyLoadState`] of a given asset `id`.
pub fn recursive_dependency_load_state(
&self,
id: impl Into<UntypedAssetId>,
) -> RecursiveDependencyLoadState {
self.get_recursive_dependency_load_state(id)
.unwrap_or(RecursiveDependencyLoadState::NotLoaded)
}
/// Returns true if the asset and all of its dependencies (recursive) have been loaded.
pub fn is_loaded_with_dependencies(&self, id: impl Into<UntypedAssetId>) -> bool {
let id = id.into();
self.load_state(id) == LoadState::Loaded
&& self.recursive_dependency_load_state(id) == RecursiveDependencyLoadState::Loaded
}
/// Returns an active handle for the given path, if the asset at the given path has already started loading,
/// or is still "alive".
pub fn get_handle<'a, A: Asset>(&self, path: impl Into<AssetPath<'a>>) -> Option<Handle<A>> {
self.get_path_and_type_id_handle(&path.into(), TypeId::of::<A>())
.map(|h| h.typed_debug_checked())
}
/// Get a `Handle` from an `AssetId`.
///
/// This only returns `Some` if `id` is derived from a `Handle` that was
/// loaded through an `AssetServer`, otherwise it returns `None`.
///
/// Consider using [`Assets::get_strong_handle`] in the case the `Handle`
/// comes from [`Assets::add`].
pub fn get_id_handle<A: Asset>(&self, id: AssetId<A>) -> Option<Handle<A>> {
self.get_id_handle_untyped(id.untyped()).map(|h| h.typed())
}
/// Get an `UntypedHandle` from an `UntypedAssetId`.
/// See [`AssetServer::get_id_handle`] for details.
pub fn get_id_handle_untyped(&self, id: UntypedAssetId) -> Option<UntypedHandle> {
self.data.infos.read().get_id_handle(id)
}
/// Returns `true` if the given `id` corresponds to an asset that is managed by this [`AssetServer`].
/// Otherwise, returns `false`.
pub fn is_managed(&self, id: impl Into<UntypedAssetId>) -> bool {
self.data.infos.read().contains_key(id.into())
}
/// Returns an active untyped asset id for the given path, if the asset at the given path has already started loading,
/// or is still "alive".
/// Returns the first ID in the event of multiple assets being registered against a single path.
///
/// # See also
/// [`get_path_ids`][Self::get_path_ids] for all handles.
pub fn get_path_id<'a>(&self, path: impl Into<AssetPath<'a>>) -> Option<UntypedAssetId> {
let infos = self.data.infos.read();
let path = path.into();
let mut ids = infos.get_path_ids(&path);
ids.next()
}
/// Returns all active untyped asset IDs for the given path, if the assets at the given path have already started loading,
/// or are still "alive".
/// Multiple IDs will be returned in the event that a single path is used by multiple [`AssetLoader`]'s.
pub fn get_path_ids<'a>(&self, path: impl Into<AssetPath<'a>>) -> Vec<UntypedAssetId> {
let infos = self.data.infos.read();
let path = path.into();
infos.get_path_ids(&path).collect()
}
/// Returns an active untyped handle for the given path, if the asset at the given path has already started loading,
/// or is still "alive".
/// Returns the first handle in the event of multiple assets being registered against a single path.
///
/// # See also
/// [`get_handles_untyped`][Self::get_handles_untyped] for all handles.
pub fn get_handle_untyped<'a>(&self, path: impl Into<AssetPath<'a>>) -> Option<UntypedHandle> {
let infos = self.data.infos.read();
let path = path.into();
let mut handles = infos.get_path_handles(&path);
handles.next()
}
/// Returns all active untyped handles for the given path, if the assets at the given path have already started loading,
/// or are still "alive".
/// Multiple handles will be returned in the event that a single path is used by multiple [`AssetLoader`]'s.
pub fn get_handles_untyped<'a>(&self, path: impl Into<AssetPath<'a>>) -> Vec<UntypedHandle> {
let infos = self.data.infos.read();
let path = path.into();
infos.get_path_handles(&path).collect()
}
/// Returns an active untyped handle for the given path and [`TypeId`], if the asset at the given path has already started loading,
/// or is still "alive".
pub fn get_path_and_type_id_handle(
&self,
path: &AssetPath,
type_id: TypeId,
) -> Option<UntypedHandle> {
let infos = self.data.infos.read();
let path = path.into();
infos.get_path_and_type_id_handle(&path, type_id)
}
/// Returns the path for the given `id`, if it has one.
pub fn get_path(&self, id: impl Into<UntypedAssetId>) -> Option<AssetPath> {
let infos = self.data.infos.read();
let info = infos.get(id.into())?;
Some(info.path.as_ref()?.clone())
}
/// Returns the [`AssetServerMode`] this server is currently in.
pub fn mode(&self) -> AssetServerMode {
self.data.mode
}
/// Pre-register a loader that will later be added.
///
/// Assets loaded with matching extensions will be blocked until the
/// real loader is added.
pub fn preregister_loader<L: AssetLoader>(&self, extensions: &[&str]) {
self.data.loaders.write().reserve::<L>(extensions);
}
/// Retrieve a handle for the given path. This will create a handle (and [`AssetInfo`]) if it does not exist
pub(crate) fn get_or_create_path_handle<'a, A: Asset>(
&self,
path: impl Into<AssetPath<'a>>,
meta_transform: Option<MetaTransform>,
) -> Handle<A> {
let mut infos = self.data.infos.write();
infos
.get_or_create_path_handle::<A>(
path.into().into_owned(),
HandleLoadingMode::NotLoading,
meta_transform,
)
.0
}
pub(crate) async fn get_meta_loader_and_reader<'a>(
&'a self,
asset_path: &'a AssetPath<'_>,
asset_type_id: Option<TypeId>,
) -> Result<
(
Box<dyn AssetMetaDyn>,
Arc<dyn ErasedAssetLoader>,
Box<Reader<'a>>,
),
AssetLoadError,
> {
let source = self.get_source(asset_path.source())?;
// NOTE: We grab the asset byte reader first to ensure this is transactional for AssetReaders like ProcessorGatedReader
// The asset byte reader will "lock" the processed asset, preventing writes for the duration of the lock.
// Then the meta reader, if meta exists, will correspond to the meta for the current "version" of the asset.
// See ProcessedAssetInfo::file_transaction_lock for more context
let asset_reader = match self.data.mode {
AssetServerMode::Unprocessed { .. } => source.reader(),
AssetServerMode::Processed { .. } => source.processed_reader()?,
};
let reader = asset_reader.read(asset_path.path()).await?;
let read_meta = match &self.data.meta_check {
AssetMetaCheck::Always => true,
AssetMetaCheck::Paths(paths) => paths.contains(asset_path),
AssetMetaCheck::Never => false,
};
if read_meta {
match asset_reader.read_meta_bytes(asset_path.path()).await {
Ok(meta_bytes) => {
// TODO: this isn't fully minimal yet. we only need the loader
let minimal: AssetMetaMinimal =
ron::de::from_bytes(&meta_bytes).map_err(|e| {
AssetLoadError::DeserializeMeta {
path: asset_path.clone_owned(),
error: DeserializeMetaError::DeserializeMinimal(e).into(),
}
})?;
let loader_name = match minimal.asset {
AssetActionMinimal::Load { loader } => loader,
AssetActionMinimal::Process { .. } => {
return Err(AssetLoadError::CannotLoadProcessedAsset {
path: asset_path.clone_owned(),
})
}
AssetActionMinimal::Ignore => {
return Err(AssetLoadError::CannotLoadIgnoredAsset {
path: asset_path.clone_owned(),
})
}
};
let loader = self.get_asset_loader_with_type_name(&loader_name).await?;
let meta = loader.deserialize_meta(&meta_bytes).map_err(|e| {
AssetLoadError::DeserializeMeta {
path: asset_path.clone_owned(),
error: e.into(),
}
})?;
Ok((meta, loader, reader))
}
Err(AssetReaderError::NotFound(_)) => {
// TODO: Handle error transformation
let loader = {
self.data
.loaders
.read()
.find(None, asset_type_id, None, Some(asset_path))
};
let error = || AssetLoadError::MissingAssetLoader {
loader_name: None,
asset_type_id,
extension: None,
asset_path: Some(asset_path.to_string()),
};
let loader = loader.ok_or_else(error)?.get().await.map_err(|_| error())?;
let meta = loader.default_meta();
Ok((meta, loader, reader))
}
Err(err) => Err(err.into()),
}
} else {
let loader = {
self.data
.loaders
.read()
.find(None, asset_type_id, None, Some(asset_path))
};
let error = || AssetLoadError::MissingAssetLoader {
loader_name: None,
asset_type_id,
extension: None,
asset_path: Some(asset_path.to_string()),
};
let loader = loader.ok_or_else(error)?.get().await.map_err(|_| error())?;
let meta = loader.default_meta();
Ok((meta, loader, reader))
}
}
pub(crate) async fn load_with_meta_loader_and_reader(
&self,
asset_path: &AssetPath<'_>,
meta: Box<dyn AssetMetaDyn>,
loader: &dyn ErasedAssetLoader,
reader: &mut Reader<'_>,
load_dependencies: bool,
populate_hashes: bool,
) -> Result<ErasedLoadedAsset, AssetLoadError> {
// TODO: experiment with this
let asset_path = asset_path.clone_owned();
let load_context =
LoadContext::new(self, asset_path.clone(), load_dependencies, populate_hashes);
loader.load(reader, meta, load_context).await.map_err(|e| {
AssetLoadError::AssetLoaderError(AssetLoaderError {
path: asset_path.clone_owned(),
loader_name: loader.type_name(),
error: e.into(),
})
})
}
}
/// A system that manages internal [`AssetServer`] events, such as finalizing asset loads.
pub fn handle_internal_asset_events(world: &mut World) {
world.resource_scope(|world, server: Mut<AssetServer>| {
let mut infos = server.data.infos.write();
let mut untyped_failures = vec![];
for event in server.data.asset_event_receiver.try_iter() {
match event {
InternalAssetEvent::Loaded { id, loaded_asset } => {
infos.process_asset_load(
id,
loaded_asset,
world,
&server.data.asset_event_sender,
);
}
InternalAssetEvent::LoadedWithDependencies { id } => {
let sender = infos
.dependency_loaded_event_sender
.get(&id.type_id())
.expect("Asset event sender should exist");
sender(world, id);
}
InternalAssetEvent::Failed { id, path, error } => {
infos.process_asset_fail(id, error.clone());
// Send untyped failure event
untyped_failures.push(UntypedAssetLoadFailedEvent {
id,
path: path.clone(),
error: error.clone(),
});
// Send typed failure event
let sender = infos
.dependency_failed_event_sender
.get(&id.type_id())
.expect("Asset failed event sender should exist");
sender(world, id, path, error);
}
}
}
if !untyped_failures.is_empty() {
world.send_event_batch(untyped_failures);
}
fn queue_ancestors(
asset_path: &AssetPath,
infos: &AssetInfos,
paths_to_reload: &mut HashSet<AssetPath<'static>>,
) {
if let Some(dependants) = infos.loader_dependants.get(asset_path) {
for dependant in dependants {
paths_to_reload.insert(dependant.to_owned());
queue_ancestors(dependant, infos, paths_to_reload);
}
}
}
let reload_parent_folders = |path: PathBuf, source: &AssetSourceId<'static>| {
let mut current_folder = path;
while let Some(parent) = current_folder.parent() {
current_folder = parent.to_path_buf();
let parent_asset_path =
AssetPath::from(current_folder.clone()).with_source(source.clone());
for folder_handle in infos.get_path_handles(&parent_asset_path) {
info!("Reloading folder {parent_asset_path} because the content has changed");
server.load_folder_internal(folder_handle.id(), parent_asset_path.clone());
}
}
};
let mut paths_to_reload = HashSet::new();
let mut handle_event = |source: AssetSourceId<'static>, event: AssetSourceEvent| {
match event {
// TODO: if the asset was processed and the processed file was changed, the first modified event
// should be skipped?
AssetSourceEvent::ModifiedAsset(path) | AssetSourceEvent::ModifiedMeta(path) => {
let path = AssetPath::from(path).with_source(source);
queue_ancestors(&path, &infos, &mut paths_to_reload);
paths_to_reload.insert(path);
}
AssetSourceEvent::RenamedFolder { old, new } => {
reload_parent_folders(old, &source);
reload_parent_folders(new, &source);
}
AssetSourceEvent::AddedAsset(path)
| AssetSourceEvent::RemovedAsset(path)
| AssetSourceEvent::RemovedFolder(path)
| AssetSourceEvent::AddedFolder(path) => {
reload_parent_folders(path, &source);
}
_ => {}
}
};
for source in server.data.sources.iter() {
match server.data.mode {
AssetServerMode::Unprocessed { .. } => {
if let Some(receiver) = source.event_receiver() {
for event in receiver.try_iter() {
handle_event(source.id(), event);
}
}
}
AssetServerMode::Processed { .. } => {
if let Some(receiver) = source.processed_event_receiver() {
for event in receiver.try_iter() {
handle_event(source.id(), event);
}
}
}
}
}
for path in paths_to_reload {
info!("Reloading {path} because it has changed");
server.reload(path);
}
});
}
/// Internal events for asset load results
#[allow(clippy::large_enum_variant)]
pub(crate) enum InternalAssetEvent {
Loaded {
id: UntypedAssetId,
loaded_asset: ErasedLoadedAsset,
},
LoadedWithDependencies {
id: UntypedAssetId,
},
Failed {
id: UntypedAssetId,
path: AssetPath<'static>,
error: AssetLoadError,
},
}
/// The load state of an asset.
#[derive(Component, Clone, Debug, PartialEq, Eq)]
pub enum LoadState {
/// The asset has not started loading yet
NotLoaded,
/// The asset is in the process of loading.
Loading,
/// The asset has been loaded and has been added to the [`World`]
Loaded,
/// The asset failed to load.
Failed(Box<AssetLoadError>),
}
/// The load state of an asset's dependencies.
#[derive(Component, Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum DependencyLoadState {
/// The asset has not started loading yet
NotLoaded,
/// Dependencies are still loading
Loading,
/// Dependencies have all loaded
Loaded,
/// One or more dependencies have failed to load
Failed,
}
/// The recursive load state of an asset's dependencies.
#[derive(Component, Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum RecursiveDependencyLoadState {
/// The asset has not started loading yet
NotLoaded,
/// Dependencies in this asset's dependency tree are still loading
Loading,
/// Dependencies in this asset's dependency tree have all loaded
Loaded,
/// One or more dependencies have failed to load in this asset's dependency tree
Failed,
}
/// An error that occurs during an [`Asset`] load.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
pub enum AssetLoadError {
#[error("Requested handle of type {requested:?} for asset '{path}' does not match actual asset type '{actual_asset_name}', which used loader '{loader_name}'")]
RequestedHandleTypeMismatch {
path: AssetPath<'static>,
requested: TypeId,
actual_asset_name: &'static str,
loader_name: &'static str,
},
#[error("Could not find an asset loader matching: Loader Name: {loader_name:?}; Asset Type: {loader_name:?}; Extension: {extension:?}; Path: {asset_path:?};")]
MissingAssetLoader {
loader_name: Option<String>,
asset_type_id: Option<TypeId>,
extension: Option<String>,
asset_path: Option<String>,
},
#[error(transparent)]
MissingAssetLoaderForExtension(#[from] MissingAssetLoaderForExtensionError),
#[error(transparent)]
MissingAssetLoaderForTypeName(#[from] MissingAssetLoaderForTypeNameError),
#[error(transparent)]
MissingAssetLoaderForTypeIdError(#[from] MissingAssetLoaderForTypeIdError),
#[error(transparent)]
AssetReaderError(#[from] AssetReaderError),
#[error(transparent)]
MissingAssetSourceError(#[from] MissingAssetSourceError),
#[error(transparent)]
MissingProcessedAssetReaderError(#[from] MissingProcessedAssetReaderError),
#[error("Encountered an error while reading asset metadata bytes")]
AssetMetaReadError,
#[error("Failed to deserialize meta for asset {path}: {error}")]
DeserializeMeta {
path: AssetPath<'static>,
error: Box<DeserializeMetaError>,
},
#[error("Asset '{path}' is configured to be processed. It cannot be loaded directly.")]
CannotLoadProcessedAsset { path: AssetPath<'static> },
#[error("Asset '{path}' is configured to be ignored. It cannot be loaded.")]
CannotLoadIgnoredAsset { path: AssetPath<'static> },
#[error(transparent)]
AssetLoaderError(#[from] AssetLoaderError),
#[error(transparent)]
AddAsyncError(#[from] AddAsyncError),
#[error("The file at '{}' does not contain the labeled asset '{}'; it contains the following {} assets: {}",
base_path,
label,
all_labels.len(),
all_labels.iter().map(|l| format!("'{}'", l)).collect::<Vec<_>>().join(", "))]
MissingLabel {
base_path: AssetPath<'static>,
label: String,
all_labels: Vec<String>,
},
}
#[derive(Error, Debug, Clone)]
#[error("Failed to load asset '{path}' with asset loader '{loader_name}': {error}")]
pub struct AssetLoaderError {
path: AssetPath<'static>,
loader_name: &'static str,
error: Arc<dyn std::error::Error + Send + Sync + 'static>,
}
impl PartialEq for AssetLoaderError {
/// Equality comparison for `AssetLoaderError::error` is not full (only through `TypeId`)
#[inline]
fn eq(&self, other: &Self) -> bool {
self.path == other.path
&& self.loader_name == other.loader_name
&& self.error.type_id() == other.error.type_id()
}
}
impl Eq for AssetLoaderError {}
impl AssetLoaderError {
pub fn path(&self) -> &AssetPath<'static> {
&self.path
}
}
#[derive(Error, Debug, Clone)]
#[error("An error occurred while resolving an asset added by `add_async`: {error}")]
pub struct AddAsyncError {
error: Arc<dyn std::error::Error + Send + Sync + 'static>,
}
impl PartialEq for AddAsyncError {
/// Equality comparison is not full (only through `TypeId`)
#[inline]
fn eq(&self, other: &Self) -> bool {
self.error.type_id() == other.error.type_id()
}
}
impl Eq for AddAsyncError {}
/// An error that occurs when an [`AssetLoader`] is not registered for a given extension.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[error("no `AssetLoader` found{}", format_missing_asset_ext(.extensions))]
pub struct MissingAssetLoaderForExtensionError {
extensions: Vec<String>,
}
/// An error that occurs when an [`AssetLoader`] is not registered for a given [`std::any::type_name`].
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[error("no `AssetLoader` found with the name '{type_name}'")]
pub struct MissingAssetLoaderForTypeNameError {
type_name: String,
}
/// An error that occurs when an [`AssetLoader`] is not registered for a given [`Asset`] [`TypeId`].
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[error("no `AssetLoader` found with the ID '{type_id:?}'")]
pub struct MissingAssetLoaderForTypeIdError {
pub type_id: TypeId,
}
fn format_missing_asset_ext(exts: &[String]) -> String {
if !exts.is_empty() {
format!(
" for the following extension{}: {}",
if exts.len() > 1 { "s" } else { "" },
exts.join(", ")
)
} else {
" for file with no extension".to_string()
}
}
impl std::fmt::Debug for AssetServer {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("AssetServer")
.field("info", &self.data.infos.read())
.finish()
}
}
/// This is appended to asset sources when loading a [`LoadedUntypedAsset`]. This provides a unique
/// source for a given [`AssetPath`].
const UNTYPED_SOURCE_SUFFIX: &str = "--untyped";