AMQP-CPP/include/deferreddelete.h

101 lines
2.5 KiB
C++

/**
* DeferredDelete.h
*
* Deferred callback for instructions that delete or purge queues, and that
* want to report the number of deleted messages.
*
* @copyright 2014 Copernica BV
*/
/**
* Set up namespace
*/
namespace AMQP {
/**
* We extend from the default deferred and add extra functionality
*/
class DeferredDelete : public Deferred
{
private:
/**
* Callback to execute when the instruction is completed
* @var DeleteCallback
*/
DeleteCallback _deleteCallback;
/**
* Report success for queue delete and queue purge messages
* @param messagecount Number of messages that were deleted
* @return Deferred Next deferred result
*/
virtual const std::shared_ptr<Deferred> &reportSuccess(uint32_t messagecount) const override
{
// skip if no special callback was installed
if (!_deleteCallback) return Deferred::reportSuccess();
// call the callback
_deleteCallback(messagecount);
// return next object
return _next;
}
/**
* The channel implementation may call our
* private members and construct us
*/
friend class ChannelImpl;
friend class ConsumedMessage;
public:
/**
* Protected constructor that can only be called
* from within the channel implementation
*
* Note: this constructor _should_ be protected, but because make_shared
* will then not work, we have decided to make it public after all,
* because the work-around would result in not-so-easy-to-read code.
*
* @param boolean are we already failed?
*/
DeferredDelete(bool failed = false) : Deferred(failed) {}
public:
/**
* Register a function to be called when the queue is deleted or purged
*
* Only one callback can be registered. Successive calls
* to this function will clear callbacks registered before.
*
* @param callback the callback to execute
*/
DeferredDelete &onSuccess(const DeleteCallback &callback)
{
// store callback
_deleteCallback = callback;
// allow chaining
return *this;
}
/**
* Register the function that is called when the queue is deleted or purged
* @param callback
*/
DeferredDelete &onSuccess(const SuccessCallback &callback)
{
// call base
Deferred::onSuccess(callback);
// allow chaining
return *this;
}
};
/**
* End namespace
*/
}