This is a program that watches a RabbitMQ config file containing default_user and default_pass for changes.
If the file changes, it updates the password in RabbitMQ.
Vault agent sidecar places new password into /etc/rabbitmq/conf.d/11-default_user.conf.
This sidecar (default-user-credential-updater) updates the password RabbitMQ server side by doing an HTTP PUT against the RabbitMQ Management API. This allows for default user password rotation without the need to restart RabbitMQ server.
This sidecar copies new password to /var/lib/rabbitmq/.rabbitmqadmin.conf to be used by rabbitmqadmin CLI.