VMware Cloud Director provides two extension mechanisms. Extension services can populate VMware Cloud Director objects with service-specific links. Object extensions can register interest in specific VMware Cloud Director operation and become part of the processing logic employed by those operations.
VMware Cloud Director object extensions are similar to VMware Cloud Director extension services in that both make use of the same AMQP-based message-queuing mechanisms. But where extension services typically operate by inserting service-specific links in VMware Cloud Director objects, object extensions operate by registering interest in one or more phases of a VMware Cloud Director procedure such as vApp placement or instantiation and, using information from the system, influencing the outcome of those processes in ways that reflect site-specific or customer-specific requirements.
