fix local object store

datafusion/src/datasource/object_store/local.rs

@@ -33,6 +33,8 @@ use crate::error::Result;
 
 use super::{ObjectReaderStream, SizedFile};
 
+impl ReadSeek for std::fs::File {}
+
 #[derive(Debug)]
 /// Local File System as Object Store.
 pub struct LocalFileSystem;
@@ -78,18 +80,20 @@ impl ObjectReader for LocalFileReader {
         )
     }
 
+    fn sync_reader(&self) -> Result<Box<dyn ReadSeek + Send + Sync>> {
+        Ok(Box::new(File::open(&self.file.path)?))
+    }
+
     fn sync_chunk_reader(
         &self,
         start: u64,
         length: usize,
-    ) -> Result<Box<dyn ReadSeek + Send + Sync>> {
+    ) -> Result<Box<dyn Read + Send + Sync>> {
         // A new file descriptor is opened for each chunk reader.
         // This okay because chunks are usually fairly large.
         let mut file = File::open(&self.file.path)?;
         file.seek(SeekFrom::Start(start))?;
-
         let file = BufReader::new(file.take(length as u64));
-
         Ok(Box::new(file))
     }
 

datafusion/src/datasource/object_store/mod.rs

@@ -35,6 +35,8 @@ use crate::error::{DataFusionError, Result};
 
 trait ReadSeek: Read + Seek {}
 
+impl<R: Read + Seek> ReadSeek for std::io::BufReader<R> {}
+
 /// Object Reader for one file in an object store.
 ///
 /// Note that the dynamic dispatch on the reader might
@@ -50,12 +52,10 @@ pub trait ObjectReader: Send + Sync {
         &self,
         start: u64,
         length: usize,
-    ) -> Result<Box<dyn ReadSeek + Send + Sync>>;
+    ) -> Result<Box<dyn Read + Send + Sync>>;
 
     /// Get reader for the entire file
-    fn sync_reader(&self) -> Result<Box<dyn ReadSeek + Send + Sync>> {
-        self.sync_chunk_reader(0, self.length() as usize)
-    }
+    fn sync_reader(&self) -> Result<Box<dyn ReadSeek + Send + Sync>>;
 
     /// Get the size of the file
     fn length(&self) -> u64;