refactor(tvix/store/blobsvc): drop Result<_,_> around open_write

We never returned Err here anyways, and we can still return an error
during the first (or subsequent) write(s).

Change-Id: I4b4cd3d35f6ea008e9ffe2f7b71bfc9187309e2f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8750
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>

tvix/store/src/blobservice/grpc.rs

@@ -121,9 +121,9 @@ impl BlobService for GRPCBlobService {
         }
     }
 
-    /// Returns a [Self::BlobWriter], that'll internally wrap each write in a
-    // [proto::BlobChunk] and which is passed to the
-    fn open_write(&self) -> Result<Box<dyn BlobWriter>, crate::Error> {
+    /// Returns a BlobWriter, that'll internally wrap each write in a
+    // [proto::BlobChunk], which is send to the gRPC server.
+    fn open_write(&self) -> Box<dyn BlobWriter> {
         let mut grpc_client = self.grpc_client.clone();
 
         // set up an mpsc channel passing around Bytes.
@@ -155,11 +155,11 @@ impl BlobService for GRPCBlobService {
         // … which is then turned into a [io::Write].
         let writer = SyncIoBridge::new(async_writer);
 
-        Ok(Box::new(GRPCBlobWriter {
+        Box::new(GRPCBlobWriter {
             tokio_handle: self.tokio_handle.clone(), // TODO: is the clone() ok here?
             task_and_writer: Some((task, writer)),
             digest: None,
-        }))
+        })
     }
 }
 

tvix/store/src/blobservice/memory.rs

@@ -30,8 +30,8 @@ impl BlobService for MemoryBlobService {
     }
 
     #[instrument(skip(self))]
-    fn open_write(&self) -> Result<Box<dyn BlobWriter>, Error> {
-        Ok(Box::new(MemoryBlobWriter::new(self.db.clone())))
+    fn open_write(&self) -> Box<dyn BlobWriter> {
+        Box::new(MemoryBlobWriter::new(self.db.clone()))
     }
 }
 

tvix/store/src/blobservice/mod.rs

@@ -24,8 +24,7 @@ pub trait BlobService: Send + Sync {
 
     /// Insert a new blob into the store. Returns a [BlobWriter], which
     /// implements [io::Write] and a [BlobWriter::close].
-    /// TODO: is there any reason we want this to be a Result<>, and not just T?
-    fn open_write(&self) -> Result<Box<dyn BlobWriter>, Error>;
+    fn open_write(&self) -> Box<dyn BlobWriter>;
 }
 
 /// A [io::Write] that you need to close() afterwards, and get back the digest

tvix/store/src/blobservice/sled.rs

@@ -46,8 +46,8 @@ impl BlobService for SledBlobService {
     }
 
     #[instrument(skip(self))]
-    fn open_write(&self) -> Result<Box<dyn BlobWriter>, Error> {
-        Ok(Box::new(SledBlobWriter::new(self.db.clone())))
+    fn open_write(&self) -> Box<dyn BlobWriter> {
+        Box::new(SledBlobWriter::new(self.db.clone()))
     }
 }