npgsql连接与ssl等待

Question

I setup a listener for notification from postresql through npgsql in vb.net. The sub just opens a new ssl connection and starts a new thread with a loop waiting for notification. Here below is the code

Public Sub StartListening()
    If mConnString Is Nothing Then
        Main_Form.WriteMessage("Not connected")
    End If
    Try
        connection = New NpgsqlConnection(mConnString) With {
            .ProvideClientCertificatesCallback = New ProvideClientCertificatesCallback(AddressOf MyProvideClientCertificates)
        }
        connection.Open()
        If connection.State = ConnectionState.Open Then
            Using command = New NpgsqlCommand("listen my_notification", connection)
                command.ExecuteNonQuery()
            End Using
        End If

        AddHandler connection.Notification, New NotificationEventHandler(AddressOf OnNotification)
        Dim thread As New Thread(
            Sub()
                While True
                    connection.Wait()
                End While
            End Sub
        )
        thread.Start()

    Catch ex As Exception
        Main_Form.WriteMessage("Error:" +  ex.Message)
    End Try
End Sub


Private Sub MyProvideClientCertificates(ByVal clienteCertis As X509CertificateCollection)
    Dim cert As X509Certificate2 = New X509Certificate2("mycertificate.pfx")
    clienteCertis.Add(cert)
End Sub

Everything was working fine until I introduced SSL connection: it fails on connection.Wait() saying

Wait() with timeout isn't supported when SSL is used, see https://github.com/npgsql/npgsql/issues/1501

Since actually I don't need a timeout I tried setting timeout=0 and commandtimeout=0 in connection string but error still remains and this is what I see in error stacktrace

in Npgsql.NpgsqlConnector.Wait(Int32 timeout)

in Npgsql.NpgsqlConnection.Wait(Int32 timeout)

in Npgsql.NpgsqlConnection.Wait()

Could anyone help?

Answer 1

I found a solution. I write here just in case some else has the same problem.

I changed Wait() with WaitAsync() .

To avoid continuous looping also added Await and declare the sub as Async .

Below is the code

        ....
        Dim thread As New Thread(
            Async Sub()
                While True
                    Await connection.WaitAsync()
                End While
            End Sub
        )
        thread.Start()
        ....