Topologies Updates
In Meridian the Kafka Producer uses topologies updates to send topology messages to Kafka.
Enhanced Linkd has six OnmsTopologyUpdaters
each sending its own NODES, BRIDGE, CDP, ISIS, LLDP, and OSPF protocol OnmsTopologyMessage
.
Kafka Producer implements an OnmsTopologyConsumer
that reads the OnmsTopologyMessage
to be shared over Kafka.
The Topologies updates APIs are available under opennms/features/topologies
OnmsTopologyUpdater
Three methods are required to set up an implementation class of OnmsTopologyUpdater
interface:
OnmsTopology getTopology();
OnmsTopologyProtocol getProtocol() throws OnmsTopologyException;
String getName();
An OnmsTopologyUpdater
holds the OnmsTopology
of the specified OnmsTopologyProtocol
.
To send OnmsTopologyMessage
to subscribers, the updater should register and send messages using the provided methods into OnmsTopologyDao
To register, use:
register(OnmsTopologyUpdater updater)
Only one updater per protocol is allowed to register over OnmsTopologyDao
.
To send messages to subscriber, use:
void update(OnmsTopologyUpdater updater,OnmsTopologyMessage message) throws OnmsTopologyException;
To unregister, use:
unregister(OnmsTopologyUpdater updater)
Registering updaters with OnmsTopologyDao will also provide topology using OnmsTopologyDao
.
To get a topology for a specific protocol, use:
OnmsTopology getTopology(String protocol)
OnmsTopologyRef
OnmsTopologyRef
is the topology basic interface.
All topology defined objects implement it.
The methods defining OnmsTopolgyRef are:
The ID: a unique string identifier of the topology object.
String getId();
The tool tip text: some additional information to describe the topology object.
String getToolTipText();
OnmsTopologyMessage
OnmsTopologyMessage
is defined by OnmsTopologyProtocol
, a TopologyMessageStatus
, and an OnmsTopologyRef
.
It is sent to all subscribers for the specified protocol by the registered updater via the `OnmsTopologyDao'.
OnmsTopologyProtocol
OnmsTopologyProtocol
represents a protocol.
It is defined by a string but is not case sensitive: CDP, cdp, and Cdp will define the same protocol.
An OnmsTopologyUpdater
can be an updater for only one protocol.
An OnmsTopologyConsumer
can be a consumer for several protocols.
TopologyMessageStatus
TopologyMessageStatus
is an enum whose allowed values are UPDATE or DELETE.
UPDATE message means that the topology message holds information about an OnmsTopologyRef
still available in topology.
DELETE message means that the object OnmsTopologyRef
has been deleted from topology.
OnmsTopology
A topology is made by vertices and edges, each uniquely identified by an OnmsTopologyRef
.
OnmsTopology
is a SET of OnmsTopologyVertex
and a SET of OnmsTopologyEdge
.
It is also possible to set and get a default vertex.
OnmsTopologyEdge
OnmsTopologyEdge
implements OnmsTopologyRef
and represents an edge.
It is made by two OnmsTopologyPort
: the source and the target of the edge.
OnmsTopologyPort
OnmsTopologyPort
implements OnmsTopologyRef
and represents a port belonging to a vertex, so has a property to set and get the OnmsTopologyVertex
.
The port is an element of the topology because it belongs to an edge and is the connection element.
Two vertices are connected by an edge by the corresponding port.
OnmsTopologyConsumer
Three methods are required to set up an implementation class of OnmsTopologyConsumer
interface:
String getName();
Set<OnmsTopologyProtocol> getProtocols();
void consume(OnmsTopologyMessage message);
An OnmsTopologyconsumer
consumes the OnmsTopologyMessage
of the specified list OnmsTopologyProtocol
provided by the getProtocols()
method implementing the method void consume(OnmsTopologyMessage message)
.
To receive OnmsTopologyMessage
from the registered "Updaters", the "Consumer" should subscribe OnmsTopologyDao
.
To subscribe, use:
void subscribe(OnmsTopologyConsumer consumer)
To unsubscribe, use:
void unsubscribe(OnmsTopologyConsumer consumer)