The full invoice lifecycle is documented here.

1. System 36 generates invoice and “prints” it
2. Redmon intercepts that data by acting like a printer
3. Custom C# tool RawUploader writes this data to a local database
4. Custom C# tool DataQueueDispatcher uploads records from local database to CRM Printlog Raw table
5. CRM takes Raw record and parses it into a CRM Invoice record
6. CRM submits Invoice id and formats to be printed to AMQP message queue to be printed
7. Custom C# tool PrintDaemon monitors AMQP message queue and spools any waiting records to the selected printer

We use a message queue, RabbitMQ, to store invoices waiting to be printed. The RabbitMQ daemon runs on Server20081 and publishes a queue called invoice. Print tools and the CRM interface with this queue with the credentials stored in KeePass.