Create queues with limit length

[droidsyer]

Hi,
Can I configure a queue with limit of length ?
I need to create a queue with last value caching and max number of message equal to 1.
I set this policy with a command on rabbitmq server, without effects....
My problem is a queue grow up more than 1 message.
Example
1 sender publish a message per second
1 receiver receive a message one per second, but if I break it on a breakpoint then i resume from break, It will receive all message buffered on queue, what I want is receive only last value sent.

I think RabbitMQ server holds ready_messages =0
So doesn't purge oldest messages from queue, saving only last message sent.

Thanks,.

[droidsyer]

I resolved it combining:

• message with ACK
• queue with QoS (Quality of Service)
• queue with limit on "x-max-length"
  In order to configure x-max-lenght using arguments, I've just modify "declare" method of queue class.

QAmqpTable optionTable;
optionTable.insert("x-max-length",1);
queue_->declare(option, optionTable);

void declare(int options = Durable|AutoDelete, const QAmqpTable optionTable = QAmqpTable());

void QAmqpQueue::declare(int options, const QAmqpTable optionTable)
{
    Q_D(QAmqpQueue);
    d->options = options;
    d->optionsTable = optionTable;

    if (!d->opened) {
        d->delayedDeclare = true;
        return;
    }

    d->declare();
}

Added private attribute to QAmqpQueuePrivate class:

private:
    QAmqpTable optionsTable;

[mbroadst]

@droidsyer ah yes, it looks like optional arguments were omitted from both exchange and queue declare methods. Would you be willing to put a PR together for this? Also, just as a nitpick I would prefer that the parameter was called arguments like the spec. Extra bonus points if you put a test together 😄

[droidsyer]

@mbroadst I've just create a PR about this, it's my first time :-D.
Is it right?

[droidsyer]

@mbroadst Can you please be aware about "arguments and qamqpInterface.pri" pull request.
It has been tested by me, it works !