Remove Conn.Listen and Conn.Unlisten

Use Conn.Exec instead to listen or unlisten.

conn.go

@@ -66,7 +66,6 @@ type Conn struct {
 	wbuf               []byte
 	config             *ConnConfig // config used when establishing this connection
 	preparedStatements map[string]*PreparedStatement
-	channels           map[string]struct{}
 	logger             Logger
 	logLevel           LogLevel
 	fp                 *fastpath
@@ -191,7 +190,6 @@ func connect(ctx context.Context, config *ConnConfig, connInfo *pgtype.ConnInfo)
 	}
 
 	c.preparedStatements = make(map[string]*PreparedStatement)
-	c.channels = make(map[string]struct{})
 	c.cancelQueryCompleted = make(chan struct{})
 	close(c.cancelQueryCompleted)
 	c.doneChan = make(chan struct{})
@@ -573,29 +571,6 @@ func (c *Conn) deallocateContext(ctx context.Context, name string) (err error) {
 	return err
 }
 
-// Listen establishes a PostgreSQL listen/notify to channel
-func (c *Conn) Listen(channel string) error {
-	_, err := c.Exec(context.TODO(), "listen "+quoteIdentifier(channel))
-	if err != nil {
-		return err
-	}
-
-	c.channels[channel] = struct{}{}
-
-	return nil
-}
-
-// Unlisten unsubscribes from a listen channel
-func (c *Conn) Unlisten(channel string) error {
-	_, err := c.Exec(context.TODO(), "unlisten "+quoteIdentifier(channel))
-	if err != nil {
-		return err
-	}
-
-	delete(c.channels, channel)
-	return nil
-}
-
 func (c *Conn) IsAlive() bool {
 	c.mux.Lock()
 	defer c.mux.Unlock()

conn_test.go

@@ -617,7 +617,7 @@ func TestSetLogger(t *testing.T) {
 		t.Fatalf("Expected conn.SetLogger to return %v, but it was %v", nil, oldLogger)
 	}
 
-	if err := conn.Listen("foo"); err != nil {
+	if _, err := conn.Exec(context.Background(), "listen foo"); err != nil {
 		t.Fatal(err)
 	}
 
@@ -631,7 +631,7 @@ func TestSetLogger(t *testing.T) {
 		t.Fatalf("Expected conn.SetLogger to return %v, but it was %v", l1, oldLogger)
 	}
 
-	if err := conn.Listen("bar"); err != nil {
+	if _, err := conn.Exec(context.Background(), "listen bar"); err != nil {
 		t.Fatal(err)
 	}
 
@@ -657,7 +657,7 @@ func TestSetLogLevel(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if err := conn.Listen("foo"); err != nil {
+	if _, err := conn.Exec(context.Background(), "listen foo"); err != nil {
 		t.Fatal(err)
 	}
 
@@ -669,7 +669,7 @@ func TestSetLogLevel(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if err := conn.Listen("bar"); err != nil {
+	if _, err := conn.Exec(context.Background(), "listen bar"); err != nil {
 		t.Fatal(err)
 	}
 

doc.go

@@ -220,7 +220,7 @@ pgx can listen to the PostgreSQL notification system with the
 WaitForNotification function. It takes a maximum time to wait for a
 notification.
 
-    err := conn.Listen("channelname")
+    err := conn.Exec("listen channelname")
     if err != nil {
         return nil
     }

examples/chat/main.go

@@ -60,7 +60,7 @@ func listen() {
 	}
 	defer pool.Release(conn)
 
-	conn.Listen("chat")
+	conn.Exec(context.Background(), "listen chat")
 
 	for {
 		notification, err := conn.WaitForNotification(context.Background())