Merge pull request #1144 from rigby-dane/add_row_description

Adds RowDescription to the SimpleQueryMessage

Author: sfackler

tokio-postgres/src/lib.rs

@@ -130,7 +130,7 @@ pub use crate::generic_client::GenericClient;
 pub use crate::portal::Portal;
 pub use crate::query::RowStream;
 pub use crate::row::{Row, SimpleQueryRow};
-pub use crate::simple_query::SimpleQueryStream;
+pub use crate::simple_query::{SimpleColumn, SimpleQueryStream};
 #[cfg(feature = "runtime")]
 pub use crate::socket::Socket;
 pub use crate::statement::{Column, Statement};
@@ -141,6 +141,7 @@ pub use crate::to_statement::ToStatement;
 pub use crate::transaction::Transaction;
 pub use crate::transaction_builder::{IsolationLevel, TransactionBuilder};
 use crate::types::ToSql;
+use std::sync::Arc;
 
 pub mod binary_copy;
 mod bind;
@@ -248,6 +249,8 @@ pub enum SimpleQueryMessage {
     ///
     /// The number of rows modified or selected is returned.
     CommandComplete(u64),
+    /// Column values of the proceeding row values
+    RowDescription(Arc<[SimpleColumn]>),
 }
 
 fn slice_iter<'a>(

tokio-postgres/src/simple_query.rs

@@ -85,35 +85,34 @@ impl Stream for SimpleQueryStream {
 
     fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         let this = self.project();
-        loop {
-            match ready!(this.responses.poll_next(cx)?) {
-                Message::CommandComplete(body) => {
-                    let rows = extract_row_affected(&body)?;
-                    return Poll::Ready(Some(Ok(SimpleQueryMessage::CommandComplete(rows))));
-                }
-                Message::EmptyQueryResponse => {
-                    return Poll::Ready(Some(Ok(SimpleQueryMessage::CommandComplete(0))));
-                }
-                Message::RowDescription(body) => {
-                    let columns = body
-                        .fields()
-                        .map(|f| Ok(SimpleColumn::new(f.name().to_string())))
-                        .collect::<Vec<_>>()
-                        .map_err(Error::parse)?
-                        .into();
+        match ready!(this.responses.poll_next(cx)?) {
+            Message::CommandComplete(body) => {
+                let rows = extract_row_affected(&body)?;
+                Poll::Ready(Some(Ok(SimpleQueryMessage::CommandComplete(rows))))
+            }
+            Message::EmptyQueryResponse => {
+                Poll::Ready(Some(Ok(SimpleQueryMessage::CommandComplete(0))))
+            }
+            Message::RowDescription(body) => {
+                let columns: Arc<[SimpleColumn]> = body
+                    .fields()
+                    .map(|f| Ok(SimpleColumn::new(f.name().to_string())))
+                    .collect::<Vec<_>>()
+                    .map_err(Error::parse)?
+                    .into();
 
-                    *this.columns = Some(columns);
-                }
-                Message::DataRow(body) => {
-                    let row = match &this.columns {
-                        Some(columns) => SimpleQueryRow::new(columns.clone(), body)?,
-                        None => return Poll::Ready(Some(Err(Error::unexpected_message()))),
-                    };
-                    return Poll::Ready(Some(Ok(SimpleQueryMessage::Row(row))));
-                }
-                Message::ReadyForQuery(_) => return Poll::Ready(None),
-                _ => return Poll::Ready(Some(Err(Error::unexpected_message()))),
+                *this.columns = Some(columns.clone());
+                Poll::Ready(Some(Ok(SimpleQueryMessage::RowDescription(columns))))
+            }
+            Message::DataRow(body) => {
+                let row = match &this.columns {
+                    Some(columns) => SimpleQueryRow::new(columns.clone(), body)?,
+                    None => return Poll::Ready(Some(Err(Error::unexpected_message()))),
+                };
+                Poll::Ready(Some(Ok(SimpleQueryMessage::Row(row))))
             }
+            Message::ReadyForQuery(_) => Poll::Ready(None),
+            _ => Poll::Ready(Some(Err(Error::unexpected_message()))),
         }
     }
 }

tokio-postgres/tests/test/main.rs

@@ -328,6 +328,13 @@ async fn simple_query() {
         _ => panic!("unexpected message"),
     }
     match &messages[2] {
+        SimpleQueryMessage::RowDescription(columns) => {
+            assert_eq!(columns.get(0).map(|c| c.name()), Some("id"));
+            assert_eq!(columns.get(1).map(|c| c.name()), Some("name"));
+        }
+        _ => panic!("unexpected message"),
+    }
+    match &messages[3] {
         SimpleQueryMessage::Row(row) => {
             assert_eq!(row.columns().get(0).map(|c| c.name()), Some("id"));
             assert_eq!(row.columns().get(1).map(|c| c.name()), Some("name"));
@@ -336,7 +343,7 @@ async fn simple_query() {
         }
         _ => panic!("unexpected message"),
     }
-    match &messages[3] {
+    match &messages[4] {
         SimpleQueryMessage::Row(row) => {
             assert_eq!(row.columns().get(0).map(|c| c.name()), Some("id"));
             assert_eq!(row.columns().get(1).map(|c| c.name()), Some("name"));
@@ -345,11 +352,11 @@ async fn simple_query() {
         }
         _ => panic!("unexpected message"),
     }
-    match messages[4] {
+    match messages[5] {
         SimpleQueryMessage::CommandComplete(2) => {}
         _ => panic!("unexpected message"),
     }
-    assert_eq!(messages.len(), 5);
+    assert_eq!(messages.len(), 6);
 }
 
 #[tokio::test]