[SOLVED]Problem when using second socket.

[ealione]

I have created a multithreaded html server that can receive and send data, including images and other files. I wanted to add the ability to send messages so I created a different library that connects to a host (e.g. smtp.google.com) and acts as a simple smtp client

socket->connectToHost(host, port);

and after logging in it writes my message

socket->write(text.toUtf8() + "\r\n");

If I test this on its own it works as expected and all messages get send.

After invoking this from my server though I get an error.

The server listens for traffic using another socket. When a user connects and visits a link for example I try to use my smtp client to send an email only to get this error

QIODevice::write: device not open

[mcosta]

Sorry,

can you post the code that is not working??
Do you wait for connected() signal before using write()?

[ealione]

Yes I do wait for the socket to connect using

if (!socket->waitForConnected(connectionTimeout))
{
    return false;
}

And its hard to post the code as it has turned out to be quite lengthy. Yet my smtp client is a barebones version of this . Any changes that I have made could not be responsible as the way I connect and send the data is the same, and as I said it works fine by itself. As for the http server it contains a worker class that deals with sockets (moves them into a separate thread, connects to the host etc) and a tcpServer that uses the worker class in order to deal with multiple connections.

[mcosta]

Is write() called just after that??

[ealione]

No after that I wait for the smtp server to respond using

waitForResponse();

after that I follow with all the procedure that has to take place in order to communicate with an smtp server, like sending the EHLO/HELO message

socket->write(text.toUtf8() + "\r\n");
if (! socket->waitForBytesWritten(sendMessageTimeout))
{
  throw SendMessageTimeoutException();
}

[mcosta]

Seems that socket is not connected when you use write().
I suggest to handle the QAbstractSocket::stateChanged() signal to understand when the state changes after connection

[ealione]

I did and it seems that it never changes state. I do not even connect with smtp.google when I use this class form inside my http server, which is weird as it connects just fine otherwise.

[mcosta]

Are you sure your socket is not changed is some part in the code??

[ealione]

Yup you are correct I should have looked more carefully at my implementation. I had a placed an ! symbol incorrectly. Now as you suggested I can see the states. This is what I get

Sending verification email.
QAbstractSocket::HostLookupState
QAbstractSocket::ConnectingState
QAbstractSocket::ConnectedState
Failed to connect to host! 

The last comment comes from

smtp.connectToHost()

Seems that it returns false, but at least this is a step forward.

[mcosta]

Are you sure you don't need to have a SSL socket?? I think at least smtp.gmail.com requires it

[ealione]

Yup that was it. Realised it just before I read your comment.
I am marking this as solved, thanks for the help mcosta.

[mcosta]

You're welcome