Watching

vfs/src/std_backend.rs

@@ -1,21 +1,40 @@
 use std::fs;
 use std::io;
 use std::path::Path;
+use std::sync::mpsc;
+use std::time::Duration;
+
+use notify::{watcher, DebouncedEvent, RecommendedWatcher, RecursiveMode, Watcher};
 
 use crate::{DirEntry, Metadata, ReadDir, VfsBackend};
 
-pub struct StdBackend;
+pub struct StdBackend {
+    watcher: RecommendedWatcher,
+    watcher_receiver: mpsc::Receiver<DebouncedEvent>,
+}
+
+impl StdBackend {
+    pub fn new() -> StdBackend {
+        let (tx, rx) = mpsc::channel();
+        let watcher = watcher(tx, Duration::from_millis(50)).unwrap();
+
+        Self {
+            watcher,
+            watcher_receiver: rx,
+        }
+    }
+}
 
 impl VfsBackend for StdBackend {
-    fn read(&self, path: &Path) -> io::Result<Vec<u8>> {
+    fn read(&mut self, path: &Path) -> io::Result<Vec<u8>> {
         fs::read(path)
     }
 
-    fn write(&self, path: &Path, data: &[u8]) -> io::Result<()> {
+    fn write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
         fs::write(path, data)
     }
 
-    fn read_dir(&self, path: &Path) -> io::Result<ReadDir> {
+    fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
         let inner = fs::read_dir(path)?.map(|entry| {
             Ok(DirEntry {
                 path: entry?.path(),
@@ -27,11 +46,23 @@ impl VfsBackend for StdBackend {
         })
     }
 
-    fn metadata(&self, path: &Path) -> io::Result<Metadata> {
+    fn metadata(&mut self, path: &Path) -> io::Result<Metadata> {
         let inner = fs::metadata(path)?;
 
         Ok(Metadata {
             is_file: inner.is_file(),
         })
     }
+
+    fn watch(&mut self, path: &Path) -> io::Result<()> {
+        self.watcher
+            .watch(path, RecursiveMode::NonRecursive)
+            .map_err(|inner| io::Error::new(io::ErrorKind::Other, inner))
+    }
+
+    fn unwatch(&mut self, path: &Path) -> io::Result<()> {
+        self.watcher
+            .unwatch(path)
+            .map_err(|inner| io::Error::new(io::ErrorKind::Other, inner))
+    }
 }