you can use RabbitMQ API to get count or messages :
/api/queues/vhost/name/get
Get messages from a queue. (This is not an HTTP GET as it will alter the state of the queue.) You should post a body looking like:
{"count":5,"requeue":true,"encoding":"auto","truncate":50000}
count controls the maximum number of messages to get. You may get fewer messages than this if the queue cannot immediately provide them.
requeue determines whether the messages will be removed from the queue. If requeue is true they will be requeued - but their redelivered flag will be set. encoding must be either "auto" (in which case the payload will be returned as a string if it is valid UTF-8, and base64 encoded otherwise), or "base64" (in which case the payload will always be base64 encoded). If truncate is present it will truncate the message payload if it is larger than the size given (in bytes). truncate is optional; all other keys are mandatory.
Please note that the publish / get paths in the HTTP API are intended for injecting test messages, diagnostics etc - they do not implement reliable delivery and so should be treated as a sysadmin's tool rather than a general API for messaging.
http://hg.rabbitmq.com/rabbitmq-management/raw-file/rabbitmq_v3_1_3/priv/www/api/index.html