A custom RabbitMQ Exchange to provide unique incrementing identifiers for messages sent to it.
The exchange "stamps" the message header with the identifier then forward the message to a destination exchange.
The exchange type is "x-stamp".
Supplied message should contain the message header - forward_exchange e.g.
forward_exchange {your exchange name}
The forwarded message will contain the header
stamp {some number}
Each exchange of type "x-stamp" will maintain their own incrementing identifier.
For each exchange we keep an in memory-identifier.
On restart the the next identifier will resume from the current timestamp.
The trade off of the algorithm is that identifiers always increase. The downside is that there might be gaps in the identifiers.
Follow the instructions at http://www.rabbitmq.com/plugin-development.html to get a working RabbitMQ build environment.
My project https://github.com/mdevilliers/vagrant-rabbitmq-development-environment provides a vagrant script for automating the provisioning of a development environment.
Checkout this project to a folder under the rabbitmq-public-umbrella project
Run the tests
cd rabbitmq-stamp
make tests
Make the project
make
Create distrubution
# sets the current version of rabbit rather than working of master
current_rmq_ref = rabbitmq_v3_7_0
make dist
Tested with RabbitMQ 3..