WebAssets without filtering (#20628)

# Objective

- adopt #17889
- Fixes #5061

---------

Co-authored-by: Peter Hayman <[email protected]>
Co-authored-by: François Mockers <[email protected]>
Co-authored-by: Alice Cecile <[email protected]>
Co-authored-by: jf908 <[email protected]>
Co-authored-by: François Mockers <[email protected]>
Co-authored-by: jf908 <[email protected]>

Author: 5 people

.gitignore

@@ -22,6 +22,7 @@ Cargo.lock
 assets/**/*.meta
 crates/bevy_asset/imported_assets
 imported_assets
+.web-asset-cache
 
 # Bevy Examples
 example_showcase_config.ron

Cargo.toml

@@ -515,6 +515,15 @@ file_watcher = ["bevy_internal/file_watcher"]
 # Enables watching in memory asset providers for Bevy Asset hot-reloading
 embedded_watcher = ["bevy_internal/embedded_watcher"]
 
+# Enables downloading assets from HTTP sources. Warning: there are security implications. Read the docs on WebAssetPlugin.
+http = ["bevy_internal/http"]
+
+# Enables downloading assets from HTTPS sources. Warning: there are security implications. Read the docs on WebAssetPlugin.
+https = ["bevy_internal/https"]
+
+# Enable caching downloaded assets on the filesystem. NOTE: this cache currently never invalidates entries!
+web_asset_cache = ["bevy_internal/web_asset_cache"]
+
 # Enable stepping-based debugging of Bevy systems
 bevy_debug_stepping = [
   "bevy_internal/bevy_debug_stepping",
@@ -1911,12 +1920,24 @@ path = "examples/asset/extra_source.rs"
 doc-scrape-examples = true
 
 [package.metadata.example.extra_asset_source]
-name = "Extra asset source"
+name = "Extra Asset Source"
 description = "Load an asset from a non-standard asset source"
 category = "Assets"
 # Uses non-standard asset path
 wasm = false
 
+[[example]]
+name = "web_asset"
+path = "examples/asset/web_asset.rs"
+doc-scrape-examples = true
+required-features = ["https"]
+
+[package.metadata.example.web_asset]
+name = "Web Asset"
+description = "Load an asset from the web"
+category = "Assets"
+wasm = true
+
 [[example]]
 name = "hot_asset_reloading"
 path = "examples/asset/hot_asset_reloading.rs"

crates/bevy_asset/Cargo.toml

@@ -14,6 +14,9 @@ keywords = ["bevy"]
 file_watcher = ["notify-debouncer-full", "watch", "multi_threaded"]
 embedded_watcher = ["file_watcher"]
 multi_threaded = ["bevy_tasks/multi_threaded"]
+http = ["blocking", "ureq"]
+https = ["blocking", "ureq", "ureq/rustls"]
+web_asset_cache = []
 asset_processor = []
 watch = []
 trace = []
@@ -87,6 +90,9 @@ bevy_reflect = { path = "../bevy_reflect", version = "0.17.0-dev", default-featu
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 notify-debouncer-full = { version = "0.5.0", default-features = false, optional = true }
+# updating ureq: while ureq is semver stable, it depends on rustls which is not, meaning unlikely but possible breaking changes on minor releases. https://github.com/bevyengine/bevy/pull/16366#issuecomment-2572890794
+ureq = { version = "3", optional = true, default-features = false }
+blocking = { version = "1.6", optional = true }
 
 [dev-dependencies]
 async-channel = "2"

crates/bevy_asset/src/io/mod.rs

@@ -14,6 +14,8 @@ pub mod memory;
 pub mod processor_gated;
 #[cfg(target_arch = "wasm32")]
 pub mod wasm;
+#[cfg(any(feature = "http", feature = "https"))]
+pub mod web;
 
 #[cfg(test)]
 pub mod gated;
@@ -48,7 +50,8 @@ pub enum AssetReaderError {
     Io(Arc<std::io::Error>),
 
     /// The HTTP request completed but returned an unhandled [HTTP response status code](https://developer.mozilla.org/en-US/docs/Web/HTTP/Status).
-    /// If the request fails before getting a status code (e.g. request timeout, interrupted connection, etc), expect [`AssetReaderError::Io`].
+    /// - If the request returns a 404 error, expect [`AssetReaderError::NotFound`].
+    /// - If the request fails before getting a status code (e.g. request timeout, interrupted connection, etc), expect [`AssetReaderError::Io`].
     #[error("Encountered HTTP status {0:?} when loading asset")]
     HttpError(u16),
 }
@@ -764,11 +767,16 @@ impl Reader for SliceReader<'_> {
     }
 }
 
-/// Appends `.meta` to the given path.
+/// Appends `.meta` to the given path:
+/// - `foo` becomes `foo.meta`
+/// - `foo.bar` becomes `foo.bar.meta`
 pub(crate) fn get_meta_path(path: &Path) -> PathBuf {
     let mut meta_path = path.to_path_buf();
     let mut extension = path.extension().unwrap_or_default().to_os_string();
-    extension.push(".meta");
+    if !extension.is_empty() {
+        extension.push(".");
+    }
+    extension.push("meta");
     meta_path.set_extension(extension);
     meta_path
 }
@@ -785,3 +793,24 @@ impl Stream for EmptyPathStream {
         Poll::Ready(None)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn get_meta_path_no_extension() {
+        assert_eq!(
+            get_meta_path(Path::new("foo")).to_str().unwrap(),
+            "foo.meta"
+        );
+    }
+
+    #[test]
+    fn get_meta_path_with_extension() {
+        assert_eq!(
+            get_meta_path(Path::new("foo.bar")).to_str().unwrap(),
+            "foo.bar.meta"
+        );
+    }
+}

crates/bevy_asset/src/io/wasm.rs

@@ -52,7 +52,8 @@ fn js_value_to_err(context: &str) -> impl FnOnce(JsValue) -> std::io::Error + '_
 }
 
 impl HttpWasmAssetReader {
-    async fn fetch_bytes(&self, path: PathBuf) -> Result<impl Reader, AssetReaderError> {
+    // Also used by [`WebAssetReader`](crate::web::WebAssetReader)
+    pub(crate) async fn fetch_bytes(&self, path: PathBuf) -> Result<impl Reader, AssetReaderError> {
         // The JS global scope includes a self-reference via a specializing name, which can be used to determine the type of global context available.
         let global: Global = js_sys::global().unchecked_into();
         let promise = if !global.window().is_undefined() {