This document discusses caching and invalidating data using the NonPersistentManagedObjectStore in Mule. It shows how to configure caching in a flow using the cache scope, and how to configure the caching strategy to use the NonPersistentManagedObjectStore. It then demonstrates testing the cached web service, invalidating the cache to force hitting the database again, and configuring a flow to clear the entire cache.

1. Caching and invalidating
with managed-store

2. Today’s topic we will be discussing the
NonPersistentManagedObjectStore and we
will not be doing any complex Caching
configuration with spring beans in our Mule
config.
.

3. How ??? I will show you how
.

4. So, let us consider we have configured a web service with
the Mule cache scope in following way:-

5. <flow name="ServiceFlow" doc:name="ServiceFlow">
<http:inbound-endpoint exchange-pattern="request-response" host="localhost"
port="8082" path="mainData" doc:name="HTTP" />
<object-to-string-transformer doc:name="Object to String"/>
<ee:cache doc:name="Cache" cachingStrategy-ref="cachingStrategy" >
<vm:outbound-endpoint exchange-pattern="request-response" path="Flow1-WT-Main"
doc:name="VM"/>
<object-to-string-transformer doc:name="Object to String"/>
</ee:cache>
</flow>
<flow name="ServiceFlow2" doc:name="ServiceFlow2">
<vm:inbound-endpoint exchange-pattern="request-response" path="Flow1-WT-Main"
doc:name="VM"/>
<cxf:jaxws-service serviceClass="com.test.services.schema.maindata.v1.MainData"
doc:name="SOAP"/>
<component class="com.test.services.schema.maindata.v1.Impl.MainDataImpl"
doc:name="JavaMain_ServiceImpl"/>
</flow>
Corresponding Mule flow will be :-

6. Now we will configure our cachingStrategy with
NonPersistentManagedObjectStore as follows:-
<ee:object-store-caching-strategy name="cachingStrategy"
doc:name="cachingStrategy">
<managed-store
storeName="myNonPersistentManagedObjectStore"
maxEntries="-1" entryTTL="20000"
expirationInterval="5000"/> </ee:object-
store-caching-strategy>
So it is very simple right ?

7. In next step we will be running and testing the
application. This web servicewill intereact with
database retrieve a row from the database and show
the row value in the SOAP response.

8. Here how we will test the web service :-
You can see that we have used SoapUI to test the web service.
Now when we hit the service, you can see in the SOAP request, it
takes id as input and then fetches all the data from the database
for that id.

9. Now, what we will do is manually deleting the entire
row from the database. In my case, I have used sql
server and deleted the row from the table using a SQL
query:-

10. With this in place, if we again hit the service, we will
get the same response as we got earlier:-

11. You can see that, though the entire row is deleted
from the database table, it’s still showing the
response, which means it is fetching the response
from cache and not hitting the actual database

12. Now, let’s create a Mule flow that will invalidate and
clear all the Cache
So, with following flow we can clear all the Cache
that has been used:-

13. Corresponding Mule config will be :-
<flow name="cacheinvalidate"
doc:name="cacheinvalidate"> <http:inbound-
endpoint exchange-pattern="request-response"
address="http://localhost:8083/invalidate"
doc:name="HTTP"/> <object-to-string-
transformer doc:name="Object to String"/>
<ee:invalidate-cache cachingStrategy-
ref="cachingStrategy"/> <set-payload
value="All cache invalidated" doc:name="Set Payload"/>
</flow>
As we can see the above flow will use ee:invalidate-cache
to clear all the cache.

14. Now if we hit the url:-
http://localhost:8083/invalidate following way :-

15. So, we can hit the web service again to test the
output.
So, now if we hit service again after the cache has
been invalidated, we will find the following result
As you can see, it clearly shows no records are there in the
database, which means the cache has invalidated successfully
and the service is actually hitting the database.

16. It’s simple example.. isn’t it … we don’t need to
configure any complex configuration for the cache as
compared to the configuration we need to do in case
of using cache with EHCache.

17. Hope you enjoyed the simple usage of Cache with
NonPersistentManagedObjectStore and the way
of invalidating it.