1.5 KiB
Group Membership
Basic operations
One of the feature provided by the coordinator is the ability to handle group membership. Once a group is created, any coordinator can join the group and become a member of it. Any coordinator can be notified when a members joins or leaves the group.
../../../examples/group_membership.py
Note that all the operation are asynchronous. That means you cannot
be sure that your group has been created or joined before you call the
tooz.coordination.CoordAsyncResult.get method.
You can also leave a group using the tooz.coordination.CoordinationDriver.leave_group
method. The list of all available groups is retrievable via the tooz.coordination.CoordinationDriver.get_groups
method.
Watching Group Changes
It's possible to watch and get notified when the member list of a group changes. That's useful to run callback functions whenever something happens in that group.
../../../examples/group_membership_watch.py
Using tooz.coordination.CoordinationDriver.watch_join_group
and tooz.coordination.CoordinationDriver.watch_leave_group
your application can be notified each time a member join or leave a
group. To stop watching an event, the two methods tooz.coordination.CoordinationDriver.unwatch_join_group
and tooz.coordination.CoordinationDriver.unwatch_leave_group
allow to unregister a particular callback.