refactor(tvix/[ca]store): use auto_impl

This implements BS, DS, PS for Box'ed or Arc'ed variants of it with less
code, and less potential to accidentially forget to proxy default trait
methods for blanked impls, as fixed in cl/12658.

Change-Id: If2cdbb563a73792038ebe7bff45d6f880214855b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12661
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: edef <edef@edef.eu>

tvix/castore/Cargo.toml

@@ -52,6 +52,7 @@ vm-memory = { workspace = true, optional = true }
 vmm-sys-util = { workspace = true, optional = true }
 virtio-bindings = { workspace = true, optional = true }
 wu-manber = { workspace = true }
+auto_impl = "1.2.0"
 
 [build-dependencies]
 prost-build = { workspace = true }

tvix/castore/src/blobservice/mod.rs

@@ -1,5 +1,6 @@
 use std::io;
 
+use auto_impl::auto_impl;
 use tonic::async_trait;
 
 use crate::composition::{Registry, ServiceBuilder};
@@ -29,6 +30,7 @@ pub use self::object_store::{ObjectStoreBlobService, ObjectStoreBlobServiceConfi
 /// which will implement a writer interface, and also provides a close funtion,
 /// to finalize a blob and get its digest.
 #[async_trait]
+#[auto_impl(&, &mut, Arc, Box)]
 pub trait BlobService: Send + Sync {
     /// Check if the service has the blob, by its content hash.
     /// On implementations returning chunks, this must also work for chunks.
@@ -60,28 +62,6 @@ pub trait BlobService: Send + Sync {
     }
 }
 
-#[async_trait]
-impl<A> BlobService for A
-where
-    A: AsRef<dyn BlobService> + Send + Sync,
-{
-    async fn has(&self, digest: &B3Digest) -> io::Result<bool> {
-        self.as_ref().has(digest).await
-    }
-
-    async fn open_read(&self, digest: &B3Digest) -> io::Result<Option<Box<dyn BlobReader>>> {
-        self.as_ref().open_read(digest).await
-    }
-
-    async fn open_write(&self) -> Box<dyn BlobWriter> {
-        self.as_ref().open_write().await
-    }
-
-    async fn chunks(&self, digest: &B3Digest) -> io::Result<Option<Vec<ChunkMeta>>> {
-        self.as_ref().chunks(digest).await
-    }
-}
-
 /// A [tokio::io::AsyncWrite] that the user needs to close() afterwards for persist.
 /// On success, it returns the digest of the written blob.
 #[async_trait]

tvix/castore/src/directoryservice/combinators.rs

@@ -170,8 +170,8 @@ impl ServiceBuilder for CacheConfig {
         context: &CompositionContext,
     ) -> Result<Arc<dyn DirectoryService>, Box<dyn std::error::Error + Send + Sync + 'static>> {
         let (near, far) = futures::join!(
-            context.resolve(self.near.clone()),
-            context.resolve(self.far.clone())
+            context.resolve::<Self::Output>(self.near.clone()),
+            context.resolve::<Self::Output>(self.far.clone())
         );
         Ok(Arc::new(Cache {
             near: near?,

tvix/castore/src/directoryservice/mod.rs

@@ -1,6 +1,7 @@
 use crate::composition::{Registry, ServiceBuilder};
 use crate::{B3Digest, Directory, Error};
 
+use auto_impl::auto_impl;
 use futures::stream::BoxStream;
 use tonic::async_trait;
 mod combinators;
@@ -39,6 +40,7 @@ pub use self::bigtable::{BigtableDirectoryService, BigtableParameters};
 /// This is a simple get and put of [Directory], returning their
 /// digest.
 #[async_trait]
+#[auto_impl(&, &mut, Arc, Box)]
 pub trait DirectoryService: Send + Sync {
     /// Looks up a single Directory message by its digest.
     /// The returned Directory message *must* be valid.
@@ -80,31 +82,6 @@ pub trait DirectoryService: Send + Sync {
     fn put_multiple_start(&self) -> Box<dyn DirectoryPutter>;
 }
 
-#[async_trait]
-impl<A> DirectoryService for A
-where
-    A: AsRef<dyn DirectoryService> + Send + Sync,
-{
-    async fn get(&self, digest: &B3Digest) -> Result<Option<Directory>, Error> {
-        self.as_ref().get(digest).await
-    }
-
-    async fn put(&self, directory: Directory) -> Result<B3Digest, Error> {
-        self.as_ref().put(directory).await
-    }
-
-    fn get_recursive(
-        &self,
-        root_directory_digest: &B3Digest,
-    ) -> BoxStream<'static, Result<Directory, Error>> {
-        self.as_ref().get_recursive(root_directory_digest)
-    }
-
-    fn put_multiple_start(&self) -> Box<dyn DirectoryPutter> {
-        self.as_ref().put_multiple_start()
-    }
-}
-
 /// Provides a handle to put a closure of connected [Directory] elements.
 ///
 /// The consumer can periodically call [DirectoryPutter::put], starting from the

tvix/castore/src/fs/fuse/tests.rs

@@ -45,8 +45,8 @@ fn do_mount<P: AsRef<Path>, BS, DS>(
     show_xattr: bool,
 ) -> io::Result<FuseDaemon>
 where
-    BS: AsRef<dyn BlobService> + Send + Sync + Clone + 'static,
-    DS: AsRef<dyn DirectoryService> + Send + Sync + Clone + 'static,
+    BS: BlobService + Send + Sync + Clone + 'static,
+    DS: DirectoryService + Send + Sync + Clone + 'static,
 {
     let fs = TvixStoreFs::new(
         blob_service,

tvix/castore/src/fs/mod.rs

@@ -121,8 +121,8 @@ pub struct TvixStoreFs<BS, DS, RN> {
 
 impl<BS, DS, RN> TvixStoreFs<BS, DS, RN>
 where
-    BS: AsRef<dyn BlobService> + Clone + Send,
-    DS: AsRef<dyn DirectoryService> + Clone + Send + 'static,
+    BS: BlobService + Clone + Send,
+    DS: DirectoryService + Clone + Send + 'static,
     RN: RootNodes + Clone + 'static,
 {
     pub fn new(
@@ -186,7 +186,7 @@ where
                     .block_on({
                         let directory_service = self.directory_service.clone();
                         let parent_digest = parent_digest.to_owned();
-                        async move { directory_service.as_ref().get(&parent_digest).await }
+                        async move { directory_service.get(&parent_digest).await }
                     })?
                     .ok_or_else(|| {
                         warn!(directory.digest=%parent_digest, "directory not found");
@@ -302,8 +302,8 @@ const XATTR_NAME_BLOB_DIGEST: &[u8] = b"user.tvix.castore.blob.digest";
 
 impl<BS, DS, RN> Layer for TvixStoreFs<BS, DS, RN>
 where
-    BS: AsRef<dyn BlobService> + Clone + Send + 'static,
-    DS: AsRef<dyn DirectoryService> + Send + Clone + 'static,
+    BS: BlobService + Clone + Send + 'static,
+    DS: DirectoryService + Send + Clone + 'static,
     RN: RootNodes + Clone + 'static,
 {
     fn root_inode(&self) -> Self::Inode {
@@ -313,8 +313,8 @@ where
 
 impl<BS, DS, RN> FileSystem for TvixStoreFs<BS, DS, RN>
 where
-    BS: AsRef<dyn BlobService> + Clone + Send + 'static,
-    DS: AsRef<dyn DirectoryService> + Send + Clone + 'static,
+    BS: BlobService + Clone + Send + 'static,
+    DS: DirectoryService + Send + Clone + 'static,
     RN: RootNodes + Clone + 'static,
 {
     type Handle = u64;
@@ -674,7 +674,7 @@ where
                 match self.tokio_handle.block_on({
                     let blob_service = self.blob_service.clone();
                     let blob_digest = blob_digest.clone();
-                    async move { blob_service.as_ref().open_read(&blob_digest).await }
+                    async move { blob_service.open_read(&blob_digest).await }
                 }) {
                     Ok(None) => {
                         warn!("blob not found");