|Description:||Used to receive and process incoming messages from RabbitMQ. See the Messaging (RabbitMQ) page for more details about RabbitMQ and horizontal scaling.|
When creating a worker you need to define a routing key alias, which is used within the routing key upon sending / receiving messages to / form RabbitMQ. This can be anything you want, and the resulting routing key to call a method within the worker will be PACKAGE.ROUTING_KEY_ALIAS.METHOD.
For example, a worker was created with
./apex create worker users:user users.profile, meaning the PHP class file created
is located at /src/users/worker/user.php. When any messages are sent to RabbitMQ with the routing key users.profile.*, this PHP class will be loaded, and the
method name of the third segment of the routing key will be executed.
For example, upon creating a new user, a message is sent via RabbitMQ to users.profile.create, which loads this worker class and executes the
create() method within it.
If you're either running Apex on a single server, or this is a back-end application server, you need to run the Apex daemon. There is a bash script located at /src/apex, which is the init script for all Apex processes -- one-way messaging, two-way RPC calls, and the WebSocket server. Copy it over to the /etc/init.d/ directory of your server, CHMOD it to 0755, and with a non-root sudo user execute it to start the Apex servers. This is required in order for the messages sent to RabbitMQ to be relayed properly to the back-end application server(s), even if everything is running on the same server.
For example, change to the installation directory of Apex, and type:
sudo cp src/apex /etc/init.d/ sudo chmod 0755 /etc/init.d/apex sudo /etc/init.d/apex start