Pre/Post Actions can be very useful for implementing cascade logic
between modules inherent in different domains. It has been mentioned
several times that to best implement domain driven design concepts, it
is not recommended to use objects for relationships between entities
inherent to different domains (projects), while , in these cases, it
is strongly recommended to use ids as a mechanism to track
relationships. HyperIoT Framework’s ActionListeners represent a good
model for “listening” to what is happening on other project domains.
In fact, although today the mechanism for invoking actions is local to
the instance , in future versions pre/post notifications will be
developed also leveraging technologies such as Kafka thus allowing the
notification to reach all instances of a cluster within which
different services may be running, just as if it were a Saga Pattern.
This approach will allow each deployed domain to be self-consistent
but still receive information from events happening on other domains
and behave accordingly.
