fix: add notifications to generic client

postgres/src/generic_client.rs

@@ -1,13 +1,14 @@
 #![allow(missing_docs)]
 
-use tokio_postgres::Column;
+use fallible_iterator::FallibleIterator;
+use tokio_postgres::{Column, Notification};
 use tokio_postgres::row::RowIndex;
 use tokio_postgres::types::FromSql;
 
 use crate::types::{BorrowToSql, ToSql, Type};
 use crate::{
     Client, CopyInWriter, CopyOutReader, Error, Row, RowIter, SimpleQueryMessage, Statement,
-    ToStatement, Transaction
+    ToStatement, Transaction, Notifications
 };
 
 macro_rules! common {
@@ -106,6 +107,8 @@ pub trait GenericClient {
     type Row: GenericRow<Error = Self::Error>;
 
     common!(Self::Transaction<'_>, Self::Error);
+
+    fn block_for_notify(&mut self) -> Result<Option<Notification>, Self::Error>;
 }
 
 impl GenericClient for Client {
@@ -188,6 +191,12 @@ impl GenericClient for Client {
     fn transaction(&mut self) -> Result<Self::Transaction<'_>, Error> {
         self.transaction()
     }
+
+    fn block_for_notify(&mut self) -> Result<Option<Notification>, Error> {
+      let mut n = self.notifications();
+      let mut n = n.blocking_iter();
+      n.next()
+    }
 }
 
 macro_rules! transaction_common {
@@ -286,6 +295,10 @@ impl GenericClient for Transaction<'_> {
     type Transaction<'a> = Transaction<'a> where Self: 'a;
     type Row = Row;
     transaction_common!(Self::Transaction<'_>);
+
+    fn block_for_notify(&mut self) -> Result<Option<Notification>, Self::Error> {
+      Ok(None)
+    }
 }
 
 impl GenericRow for Row {

tokio-postgres/src/lib.rs

@@ -201,10 +201,11 @@ where
 
 /// An asynchronous notification.
 #[derive(Clone, Debug)]
+#[allow(missing_docs)]
 pub struct Notification {
-    process_id: i32,
+    pub process_id: i32,
-    channel: String,
+    pub channel: String,
-    payload: String,
+    pub payload: String,
 }
 
 impl Notification {