feat(tauri): add cache option (#13)

## Summary

Add cache option for tauri plugin.

## Test Plan

Should pass CI.

Cargo.toml

@@ -9,6 +9,7 @@ bincode            = "2.0.0-rc.3"
 biome_console      = "0.5.7"
 bpaf               = { version = "0.9.14", features = ["derive"] }
 lz4_flex           = "0.11.3"
+mime_guess         = "2.0.5"
 napi               = { version = "2.16.11", default-features = false, features = ["napi4", "async"] }
 napi-build         = "2.1.3"
 napi-derive        = "2.16.12"

crates/webview-bundle-tauri/Cargo.toml

@@ -12,6 +12,11 @@ webview-bundle = { workspace = true }
 
 async-trait   = { workspace = true }
 buildstructor = "0.5.4"
+lru           = { version = "0.12.5", optional = true }
+mime_guess    = { workspace = true }
 tauri         = { workspace = true }
 thiserror     = { workspace = true }
 tokio         = { workspace = true }
+
+[features]
+cache-lru = ["dep:lru"]

crates/webview-bundle-tauri/src/cache.rs

@@ -0,0 +1,61 @@
+use std::hash::Hash;
+use webview_bundle::Bundle;
+
+pub trait Cache<K: Hash + Eq, V> {
+  fn has(&self, key: &K) -> bool;
+  fn get(&mut self, key: &K) -> Option<&V>;
+  fn set(&mut self, key: K, value: V);
+}
+
+#[derive(Clone, Default)]
+pub struct NoopCache;
+
+impl Cache<String, Bundle> for NoopCache {
+  fn has(&self, _key: &String) -> bool {
+    false
+  }
+
+  fn get(&mut self, _key: &String) -> Option<&Bundle> {
+    None
+  }
+
+  fn set(&mut self, _key: String, _value: Bundle) {}
+}
+
+#[cfg(feature = "cache-lru")]
+#[derive(Clone)]
+pub struct LruCache<K: Hash + Eq, V> {
+  cache: lru::LruCache<K, V>,
+}
+
+#[cfg(feature = "cache-lru")]
+impl<K: Hash + Eq, V> LruCache<K, V> {
+  pub fn new(size: usize) -> Self {
+    Self {
+      cache: lru::LruCache::<K, V>::new(
+        std::num::NonZeroUsize::new(size).expect("size is not non zero"),
+      ),
+    }
+  }
+
+  pub fn unbounded() -> Self {
+    Self {
+      cache: lru::LruCache::<K, V>::unbounded(),
+    }
+  }
+}
+
+#[cfg(feature = "cache-lru")]
+impl Cache<String, Bundle> for LruCache<String, Bundle> {
+  fn has(&self, key: &String) -> bool {
+    self.cache.contains(key)
+  }
+
+  fn get(&mut self, key: &String) -> Option<&Bundle> {
+    self.cache.get(key)
+  }
+
+  fn set(&mut self, key: String, value: Bundle) {
+    self.cache.put(key, value);
+  }
+}

crates/webview-bundle-tauri/src/config.rs

@@ -1,20 +1,32 @@
+use crate::cache::Cache;
 use crate::loader::Loader;
+use webview_bundle::Bundle;
 
-pub struct Config<L: Loader + Send + Sync> {
+pub struct Config<L, C>
+where
+  L: Loader + Send + Sync,
+  C: Cache<String, Bundle> + Send + Sync,
+{
   loader: L,
+  cache: C,
 }
 
 #[buildstructor::buildstructor]
-impl<L> Config<L>
+impl<L, C> Config<L, C>
 where
   L: Loader + Send + Sync,
+  C: Cache<String, Bundle> + Send + Sync,
 {
   #[builder]
-  pub fn new(loader: L) -> Self {
-    Self { loader }
+  pub fn new(loader: L, cache: C) -> Self {
+    Self { loader, cache }
   }
 
   pub fn loader(&self) -> &L {
     &self.loader
   }
+
+  pub fn cache(&self) -> &C {
+    &self.cache
+  }
 }

crates/webview-bundle-tauri/src/lib.rs

@@ -1,20 +1,23 @@
-mod config;
-mod error;
-mod loader;
+pub mod cache;
+pub mod config;
+pub mod error;
+pub mod loader;
 
-pub use config::Config;
-pub use error::Error;
-pub use loader::{FSLoader, Loader};
+use crate::cache::Cache;
+use crate::config::Config;
+use crate::loader::Loader;
 use std::path::Path;
 use tauri::http::{Method, Response, Uri};
 use tauri::plugin::{PluginApi, TauriPlugin};
 use tauri::{plugin, AppHandle, Manager, Runtime};
+use webview_bundle::Bundle;
 
-pub fn init<R, L, F>(scheme: &'static str, config: F) -> TauriPlugin<R>
+pub fn init<R, L, C, F>(scheme: &'static str, config: F) -> TauriPlugin<R>
 where
   R: Runtime,
   L: Loader + Send + Sync + 'static,
-  F: FnOnce(&AppHandle<R>, PluginApi<R, ()>) -> Result<Config<L>, Box<dyn std::error::Error>>
+  C: Cache<String, Bundle> + Send + Sync + 'static,
+  F: FnOnce(&AppHandle<R>, PluginApi<R, ()>) -> Result<Config<L, C>, Box<dyn std::error::Error>>
     + Send
     + 'static,
 {
@@ -33,13 +36,13 @@ where
       let uri = request.uri().clone();
       let app = ctx.app_handle().clone();
       tauri::async_runtime::spawn(async move {
-        let config = app.state::<Config<L>>();
+        let config = app.state::<Config<L, C>>();
         let bundle = config.loader().load(&uri).await.unwrap();
         let filepath = uri_to_filepath(&uri);
-        let buf = bundle.read_file(filepath).unwrap();
+        let buf = bundle.read_file(&filepath).unwrap(); // TODO: handle file not found error
         responder.respond(
           Response::builder()
-            .header("content-type", "text/html")
+            .header("content-type", mime_types_from_filepath(&filepath))
             .header("content-length", buf.len())
             .status(200)
             .body(buf)
@@ -61,3 +64,11 @@ fn uri_to_filepath(uri: &Uri) -> String {
   }
   [filepath, index_html].join("/")
 }
+
+fn mime_types_from_filepath(filepath: &String) -> String {
+  let guess = mime_guess::from_path(filepath);
+  guess
+    .first()
+    .map(|x| x.to_string())
+    .unwrap_or("text/plain".to_string())
+}

examples/tauri-simple/src/main.rs

@@ -1,7 +1,9 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
 
 use tauri::{Manager, WebviewUrl};
-use webview_bundle_tauri::{Config, FSLoader};
+use webview_bundle_tauri::cache::NoopCache;
+use webview_bundle_tauri::config::Config;
+use webview_bundle_tauri::loader::FSLoader;
 
 fn main() {
   tauri::Builder::default()
@@ -10,7 +12,10 @@ fn main() {
       dir.pop();
       dir.pop();
       dir.push("examples/tauri-simple");
-      let config = Config::builder().loader(FSLoader::from_dir(dir)).build();
+      let config = Config::builder()
+        .cache(NoopCache::default())
+        .loader(FSLoader::from_dir(dir))
+        .build();
       Ok(config)
     }))
     .setup(|app| {