Hi Azeez
At present, u cannot introduce a new LB algorithm impl without code
changes. Only round-robin load balancing is supported, and the
implementation has been somewhat hard-coded to use round-robin load
balancing. Users cannot do a config change and incorporate a new
algorithm. Ideally, we should let them specify the algorithm impl in
the synapse.xml file. There are two way this may be done.
*1.*
<definitions xmlns="http://ws.apache.org/ns/synapse";>
*<loadbalanceAlgorithms>**
*
* <algorithm name="ec2-autoscale-roundrobin"**
**
implementation="org.apache.synapse.algorithms.Ec2AutoScaleRoundRobin"/>**
** </loadbalanceAlgorithms>*
<endpoint name="dynamicLB">
<dynamicLoadbalance failover="true" policy="*ec2-autoscale-roundrobin*">
<membershipHandler
class="org.apache.synapse.core.axis2.Axis2LoadBalanceMembershipHandler">
<property name="applicationDomain" value="apache.axis2.app.domain"/>
</membershipHandler>
</dynamicLoadbalance>
</endpoint>
</definitions>
We haven't yet used the synapse.xml to "define" non mediation aspects of
Synapse. We already do have a synapse.properties, which defines
datasources for use by the synapse.xml's DB mediators. So I think we
should not do this in synapse.xml, but the properties file would be good..
*2.*
<definitions xmlns="http://ws.apache.org/ns/synapse";>
<endpoint name="dynamicLB">
<dynamicLoadbalance failover="true"
*algorithm="org.apache.synapse.algorithms.Ec2AutoScaleRoundRobin"*>
<membershipHandler
class="org.apache.synapse.core.axis2.Axis2LoadBalanceMembershipHandler">
<property name="applicationDomain" value="apache.axis2.app.domain"/>
</membershipHandler>
</dynamicLoadbalance>
</endpoint>
</definitions>
Both approaches preserve backwards compatibility. Please send in your
suggestions.
I think this approach is slightly better, since its all in "one file"..
and anyway you are just defining the algorithm impl class name as a String
So between the two, I personally prefer option #2
asankha
--
Asankha C. Perera
WSO2 - http://wso2.org
http://esbmagic.blogspot.com
