The event service defines two roles for objects: the supplier role and
the consumer role. Suppliers supply event data to the event channel and
consumers receive event data from the channel. Suppliers do not need to
know the identity of the consumers, and vice versa. Consumers and
suppliers are connected to the event channel via proxies, which are managed
by ConsumerAdmin and SupplierAdmin objects.
There are four general models of communication. These are:
- The canonical push model. It allows the suppliers of events to initiate the
transfer of event data to consumers. Event channels play the role of
. Active suppliers use event channel to push data to
passive consumers registered with the event channel.
- The canonical pull model. It allows consumers to request events from
suppliers. Event channels play the role of since they
procure events on behalf of consumers. Active consumers can explicitly
pull data from passive suppliers via the event channels.
- The hybrid push/pull model. It allows consumers request events queued at
a channel by suppliers. Event channels play the role of .
Active consumers explicitly pull data deposited by active suppliers via
the event channels.
- The hybrid pull/push model. It allows the channel to pull events from
suppliers and push them to consumers. Event channels play the role of
. Active event channels can pull data from
passive suppliers to push it to passive consumers.
To get access to all definitions, e.g., exceptions,
include necessary files by using:
There are seven different interfaces supported in the service:
- ProxyPushConsumer
- ProxyPullSupplier
- ProxyPullConsumer
- ProxyPushSupplier
- ConsumerAdmin
- SupplierAdmin
- EventChannel
IDL specification for CosEventChannelAdmin: