AMQP Event

The Advanced Message Queuing Protocol (AMQP) is an open standard application layer protocol for message-oriented middleware. It delivers message orientation, queuing, routing (including point-to-point and publish-and-subscribe), reliability and security. AMQP came out of the financial industry, and is proven highly scalable in demanding environments (refer http://www.amqp.org/).

AMQP is the emerging standard for messaging and events in the cloud. For example:

• vCloud Director can publish vCloud Messages, also known as “blocking tasks,” “notifications,” or “call-outs,” related to different provisioning. An orchestrator can not only receive these events, but can also respond to them to delay execution.

• AMQP is supported with vCloud Orchestrator.

• OpenStack selected AMQP as the messaging technology for OpenStack.

AMQP is integrated with more than 70 developer platforms, providing a nice framework for event-oriented integrations.
AMQP enables event-driven capabilities of Enterprise Service Bus-style designs. It enables queuing, so automation can fetch messages when there is capacity. You can use asynchronous methods servicing requests as capacity allows when possible, and reserve real-time, synchronous methods only when absolutely needed. AMQP’s open platform is a natural choice for event and message design patterns.

Action Orchestrator can trigger processes in response to messages placed on AMQP queues/exchanges. Processes can also read messages from queues/exchanges one at a time if they want to respond to messages one at a time rather than in parallel, to operate more as a queue. Processes can submit messages to queues/exchanges.

JMS is another possible integration enabled through AMQP. AMQP has providers to place JMS messages on queues/exchanges.

To create a new AMQP event perform the following procedure:

1. Under Select Type, select AMQP Event from the dropdown list.

2. Under General, specify the following information:

   1. Display Name: Enter the unique display name for the AMQP event.

   2. Description: Enter the brief description about the AMQP event.

   3. Target: Select the target from the dropdown list. To add a new target, click +ADD NEW from the dropdown list. For more information, see AMQP Endpoint.

3. Under Criteria, specify the following information:

   1. Queue Name: Enter the name of the queue.

   2. Conditions: Click +ADD to specify the condition, enter the following information:

      1. Left Operand: Enter the value for the left operand.

      2. Operator: From the dropdown list, choose the operator to use for comparing the value:

         1. Does not match wildcard: Determines if the item does not match all items in the wildcard example

         2. Equal: Determines if the left side equals the right side (if this is a string comparison, this is case-insensitive)

         3. Match regular expression: Determines if the left side matches the regular expression specified on the right side.

         4. Matches wildcard: Determines if the left side matches the wildcard specified on the right side.

         5. Not equals: Determines if the left side does not equal the right side

      3. Right Operand: Enter the value for the right operand.

4. Click Submit, to save the changes.