Splitter & Collection Aggregator in Mule
The Splitter Flow Control splits a message into separate fragments, then sends these fragments one at a time to the next message processor in the flow. Segments are identified based on an expression parameter, usually written in Mule Expression Language (MEL), but other formats can be employed also. You can then use a Collection Aggregator Flow Control to reassemble the parts of the original message. You can also include a Resequencer Flow Control to put the parts back into the original sequence in case they are shuffled out of order.
Splitting and aggregating the message is especially useful when you intend to process the split parts in asynchronous flows running on separate servers. Together, the splitter and aggregator flow controls allow you to share the workload among several servers and still be able to reassemble the message after it’s processed.
Flow of splitter & collection aggregator :
Splitter Configuration :
Since we are giving XML input payload so we have to use xpath expression to split our payload.We are splitting by 'Employee'
The splitted files are gathered in a folder named 'splitted' in src/main/resources
Then for aggregating files we need Collection Aggregator and it doesn't require any configuration.Aggregated payload is shown in output.
URL : http://localhost:8085/api/splitter
Method : POST
Below is the input for splitter which is splitted and stored in files in a folder and aggregated by Collection Aggregator.Final aggregated output is shown in output.
Input :
<Employees>
<Employee>
<FirstName>Himanshu</FirstName>
<LastName>Pal</LastName>
<Salary>120000</Salary>
</Employee>
<Employee>
<FirstName>Sonam</FirstName>
<LastName>Sharma</LastName>
<Salary>200000</Salary>
</Employee>
<Employee>
<FirstName>Piyush</FirstName>
<LastName>Joshi</LastName>
<Salary>300000</Salary>
</Employee>
<Employee>
<FirstName>Vinod</FirstName>
<LastName>Shukla</LastName>
<Salary>800000</Salary>
</Employee>
<Employee>
<FirstName>Kunal</FirstName>
<LastName>Verma</LastName>
<Salary>500000</Salary>
</Employee>
</Employees>
Output :
XML project code :
<?xml version="1.0" encoding="UTF-8"?>
<mule xmlns:file="http://www.mulesoft.org/schema/mule/file" xmlns:http="http://www.mulesoft.org/schema/mule/http" xmlns:mulexml="http://www.mulesoft.org/schema/mule/xml" xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation"
xmlns:spring="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
http://www.mulesoft.org/schema/mule/file http://www.mulesoft.org/schema/mule/file/current/mule-file.xsd
http://www.mulesoft.org/schema/mule/xml http://www.mulesoft.org/schema/mule/xml/current/mule-xml.xsd">
<http:listener-config name="HTTP_Listener_Configuration" host="0.0.0.0" port="8085" basePath="/api" doc:name="HTTP Listener Configuration"/>
<file:connector name="File" writeToDirectory="src/main/resources/splitted" autoDelete="false" streaming="false" validateConnections="true" doc:name="File"/>
<flow name="test_splitterFlow">
<http:listener config-ref="HTTP_Listener_Configuration" path="/splitter" doc:name="HTTP"/>
<splitter expression="#[xpath('//Employee')]" doc:name="Splitter"/>
<mulexml:dom-to-xml-transformer doc:name="DOM to XML"/>
<file:outbound-endpoint path="src/main/resources/splitted" connector-ref="File" responseTimeout="10000" doc:name="File"/>
<collection-aggregator failOnTimeout="true" doc:name="Collection Aggregator">
</collection-aggregator>
<mulexml:dom-to-xml-transformer doc:name="DOM to XML"/>
</flow>
</mule>
