Chapter 5. Using the API
For more information, see the AMQ JavaScript API reference and AMQ JavaScript example suite.
5.1. Handling messaging events
AMQ JavaScript is an asynchronous event-driven API. To define how the application handles events, the user registers event-handling functions on the container
object. These functions are then called as network activity or timers trigger new events.
Example: Handling messaging events
var rhea = require("rhea"); var container = rhea.create_container(); container.on("sendable", function (event) { console.log("A message can be sent"); }); container.on("message", function (event) { console.log("A message is received"); });
These are only a few common-case events. The full set is documented in the AMQ JavaScript API reference.
5.2. Accessing event-related objects
The event
argument has attributes for accessing the object the event is regarding. For example, the connection_open
event sets the event connection
attribute.
In addition to the primary object for the event, all objects that form the context for the event are set as well. Attributes with no relevance to a particular event are null.
Example: Accessing event-related objects
event.container event.connection event.session event.sender event.receiver event.delivery event.message
5.3. Creating a container
The container is the top-level API object. It is the entry point for creating connections, and it is responsible for running the main event loop. It is often constructed with a global event handler.
Example: Creating a container
var rhea = require("rhea");
var container = rhea.create_container();
5.4. Setting the container identity
Each container instance has a unique identity called the container ID. When AMQ JavaScript makes a network connection, it sends the container ID to the remote peer. To set the container ID, pass the id
option to the create_container
method.
Example: Setting the container identity
var container = rhea.create_container({id: "job-processor-3"});
If the user does not set the ID, the library will generate a UUID when the container is constucted.