chore: Expose StripeFactory so users can write them in struct (#9)

Signed-off-by: Xuanwo <[email protected]>

src/async_arrow_reader.rs

@@ -68,7 +68,7 @@ impl<R: Send> From<Cursor<R>> for StripeFactory<R> {
     }
 }
 
-struct StripeFactory<R> {
+pub struct StripeFactory<R> {
     inner: Cursor<R>,
     is_end: bool,
 }
@@ -132,6 +132,11 @@ impl<R: AsyncChunkReader + 'static> ArrowStreamReader<R> {
         }
     }
 
+    /// Extracts the inner `StripeFactory` and `SchemaRef` from the `ArrowStreamReader`.
+    pub fn into_parts(self) -> (Option<Box<StripeFactory<R>>>, SchemaRef) {
+        (self.factory, self.schema_ref)
+    }
+
     pub fn schema(&self) -> SchemaRef {
         self.schema_ref.clone()
     }