rewrite SourceQuestionsZipReaderAsync stream

(poll_next not work)

lib/src/source.rs

@@ -218,10 +218,11 @@ pub use reader_sync::{ReadSourceQuestionsBatches, SourceQuestionsZipReader};
 pub mod reader_async {
     use crate::util::ErrorToString;
 
+    use async_stream::stream;
     use async_zip::tokio::read::seek::ZipFileReader;
     use futures_core::stream::Stream;
     use futures_core::Future;
-    use futures_util::{pin_mut, AsyncReadExt};
+    use futures_util::{pin_mut, AsyncReadExt, StreamExt};
 
     use std::pin::Pin;
     use std::task::{Context, Poll};
@@ -248,24 +249,49 @@ pub mod reader_async {
                 index: None,
             }
         }
-        async fn parse_zip_entry(
+        pub async fn get_next(
             &mut self,
-        ) -> Result<(String, Result<SourceQuestionsBatch, serde_json::Error>), String>
+        ) -> Option<Result<(String, Result<SourceQuestionsBatch, serde_json::Error>), String>>
         where
             R: AsyncRead + AsyncSeek + Unpin,
         {
-            let mut reader = self
+            let len = self.zipfile.file().entries().len();
+            if self.index.is_none() && len > 0 {
+                self.index = Some(0);
+            }
+
+            let index = &mut self.index;
+            if index.unwrap() == len {
+                return None;
+            }
+
+            let reader = self
                 .zipfile
                 .reader_with_entry(self.index.unwrap())
-                .await
-                .str_err()?;
-            let filename = reader.entry().filename().clone().into_string().str_err()?;
+                .await;
+            if let Err(error) = reader {
+                println!("{:#?}", error); // DEBUG
+                return Some(Err(error.to_string()))
+            }
+            let mut reader = reader.unwrap();
+
+            let filename = reader.entry().filename().clone().into_string().unwrap();
             let mut data: Vec<u8> = Vec::new();
-            reader.read_to_end(&mut data).await.str_err()?;
+            let readed = reader.read_to_end(&mut data).await;
+            if let Err(error) = readed {
+                return Some(Err(error.to_string()))
+            }
             let parsed: Result<SourceQuestionsBatch, _> = serde_json::from_slice(&data);
             self.index = Some(self.index.unwrap() + 1);
 
-            Ok((filename, parsed))
+            Some(Ok((filename, parsed)))
+        }
+        pub fn stream(&mut self) -> impl Stream<Item = (String, Result<SourceQuestionsBatch, serde_json::Error>)> + '_ {
+            stream! {
+                while let Some(Ok(item)) = self.get_next().await {
+                    yield item
+                }
+            }
         }
     }
 
@@ -276,21 +302,11 @@ pub mod reader_async {
         type Item = (String, Result<SourceQuestionsBatch, serde_json::Error>);
 
         fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
-            let len = self.zipfile.file().entries().len();
-            if self.index.is_none() && len > 0 {
-                self.index = Some(0);
-            }
-
-            let index = &mut self.index;
-            if index.unwrap() == len {
-                return Poll::Ready(None);
-            }
-
-            let future = self.parse_zip_entry();
+            let future = self.stream();
             pin_mut!(future);
-            match Pin::new(&mut future).poll(cx) {
-                Poll::Ready(Ok(item)) => Poll::Ready(Some(item)),
-                Poll::Ready(Err(_)) => Poll::Ready(None),
+            match Pin::new(&mut future.next()).poll(cx) {
+                Poll::Ready(Some(item)) => Poll::Ready(Some(item)),
+                Poll::Ready(None) => Poll::Ready(None),
                 Poll::Pending => Poll::Pending,
             }
         }