Expose RowIter

Author: sfackler

postgres/src/client.rs

@@ -1,8 +1,6 @@
-use crate::iter::Iter;
 #[cfg(feature = "runtime")]
 use crate::Config;
-use crate::{CopyInWriter, CopyOutReader, Statement, ToStatement, Transaction};
-use fallible_iterator::FallibleIterator;
+use crate::{CopyInWriter, CopyOutReader, RowIter, Statement, ToStatement, Transaction};
 use futures::executor;
 use tokio_postgres::tls::{MakeTlsConnect, TlsConnect};
 use tokio_postgres::types::{ToSql, Type};
@@ -183,18 +181,14 @@ impl Client {
     /// # Ok(())
     /// # }
     /// ```
-    pub fn query_raw<'a, T, I>(
-        &mut self,
-        query: &T,
-        params: I,
-    ) -> Result<impl FallibleIterator<Item = Row, Error = Error>, Error>
+    pub fn query_raw<'a, T, I>(&mut self, query: &T, params: I) -> Result<RowIter<'_>, Error>
     where
         T: ?Sized + ToStatement,
         I: IntoIterator<Item = &'a dyn ToSql>,
         I::IntoIter: ExactSizeIterator,
     {
         let stream = executor::block_on(self.0.query_raw(query, params))?;
-        Ok(Iter::new(stream))
+        Ok(RowIter::new(stream))
     }
 
     /// Creates a new prepared statement.

postgres/src/iter.rs

@@ -75,6 +75,7 @@ pub use crate::copy_out_reader::CopyOutReader;
 pub use crate::error::Error;
 #[doc(no_inline)]
 pub use crate::row::{Row, SimpleQueryRow};
+pub use crate::row_iter::RowIter;
 #[doc(no_inline)]
 pub use crate::tls::NoTls;
 pub use crate::transaction::*;
@@ -84,7 +85,7 @@ mod client;
 pub mod config;
 mod copy_in_writer;
 mod copy_out_reader;
-mod iter;
+mod row_iter;
 mod transaction;
 
 #[cfg(feature = "runtime")]

postgres/src/lib.rs

@@ -0,0 +1,34 @@
+use fallible_iterator::FallibleIterator;
+use futures::executor::{self, BlockingStream};
+use std::marker::PhantomData;
+use std::pin::Pin;
+use tokio_postgres::{Error, Row, RowStream};
+
+/// The iterator returned by `query_raw`.
+pub struct RowIter<'a> {
+    it: BlockingStream<Pin<Box<RowStream>>>,
+    _p: PhantomData<&'a mut ()>,
+}
+
+// no-op impl to extend the borrow until drop
+impl Drop for RowIter<'_> {
+    fn drop(&mut self) {}
+}
+
+impl<'a> RowIter<'a> {
+    pub(crate) fn new(stream: RowStream) -> RowIter<'a> {
+        RowIter {
+            it: executor::block_on_stream(Box::pin(stream)),
+            _p: PhantomData,
+        }
+    }
+}
+
+impl FallibleIterator for RowIter<'_> {
+    type Item = Row;
+    type Error = Error;
+
+    fn next(&mut self) -> Result<Option<Row>, Error> {
+        self.it.next().transpose()
+    }
+}

postgres/src/row_iter.rs

@@ -1,6 +1,4 @@
-use crate::iter::Iter;
-use crate::{CopyInWriter, CopyOutReader, Portal, Statement, ToStatement};
-use fallible_iterator::FallibleIterator;
+use crate::{CopyInWriter, CopyOutReader, Portal, RowIter, Statement, ToStatement};
 use futures::executor;
 use tokio_postgres::types::{ToSql, Type};
 use tokio_postgres::{Error, Row, SimpleQueryMessage};
@@ -63,18 +61,14 @@ impl<'a> Transaction<'a> {
     }
 
     /// Like `Client::query_raw`.
-    pub fn query_raw<'b, T, I>(
-        &mut self,
-        query: &T,
-        params: I,
-    ) -> Result<impl FallibleIterator<Item = Row, Error = Error>, Error>
+    pub fn query_raw<'b, T, I>(&mut self, query: &T, params: I) -> Result<RowIter<'_>, Error>
     where
         T: ?Sized + ToStatement,
         I: IntoIterator<Item = &'b dyn ToSql>,
         I::IntoIter: ExactSizeIterator,
     {
         let stream = executor::block_on(self.0.query_raw(query, params))?;
-        Ok(Iter::new(stream))
+        Ok(RowIter::new(stream))
     }
 
     /// Binds parameters to a statement, creating a "portal".
@@ -107,9 +101,9 @@ impl<'a> Transaction<'a> {
         &mut self,
         portal: &Portal,
         max_rows: i32,
-    ) -> Result<impl FallibleIterator<Item = Row, Error = Error>, Error> {
+    ) -> Result<RowIter<'_>, Error> {
         let stream = executor::block_on(self.0.query_portal_raw(portal, max_rows))?;
-        Ok(Iter::new(stream))
+        Ok(RowIter::new(stream))
     }
 
     /// Like `Client::copy_in`.