mule studio - How to print record values without repeating certain fields in dataweave in CSV format based on specific conditions -

please consider following input sample in csv

company,firstname,lastname,email rate,manule,reaya,reaya@egetmetus.org rate,sholy,bonvgy,bonvage@mollis.org 

the output should follows :

company,firstname,lastname,email rate,manule,reaya,reaya@egetmetus.org ,sholy,bonvgy,bonvage@mollis.org 

the condition : if company name repeats different records in input, should null in output csv.

please let me know if can handled in dataweave component in mule

below updated code

<?xml version="1.0" encoding="utf-8"?>  <mule xmlns:file="http://www.mulesoft.org/schema/mule/file" xmlns:dw="http://www.mulesoft.org/schema/mule/ee/dw" 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/file http://www.mulesoft.org/schema/mule/file/current/mule-file.xsd http://www.mulesoft.org/schema/mule/ee/dw http://www.mulesoft.org/schema/mule/ee/dw/current/dw.xsd">      <configuration doc:name="configuration">      <expression-language>          <global-functions>             def getcompanyname(company){                  if (flowvars.companylist contains company) {                     return "";                  }  else {                     flowvars.companylist.add(company);                     return company;                  }             }           </global-functions>      </expression-language>  </configuration>     <file:connector name="file" autodelete="true" streaming="true" validateconnections="true" doc:name="file"/>     <file:connector name="file1" autodelete="true" outputappend="true" streaming="true" validateconnections="true" doc:name="file"/>     <flow name="csvtocsvrecordemptyflow">         <file:inbound-endpoint path="src\test\resources\input" connector-ref="file" responsetimeout="10000" doc:name="file"/>         <set-variable variablename="companylist" value="[[]]" doc:name="variable"/>         <dw:transform-message doc:name="transform message">             <dw:set-payload><![cdata[%dw 1.0 %output application/csv header=true --- payload map {     companyname: getcompanyname($.company),     name:$.firstname }]]></dw:set-payload>         </dw:transform-message>          <file:outbound-endpoint path="src\test\resources\output" outputpattern="test.csv" connector-ref="file1" responsetimeout="10000" doc:name="file"/>     </flow> </mule> 

afaik, problem store used company names within memory using dataweave. don't think can done. if combine, mel global functions , dataweave, should able achieve this.

add global mel function in mule config below -

<configuration doc:name="configuration">      <expression-language>          <global-functions>             def getcompanyname(name){                  if (flowvars.companylist contains name) {                     return "";                  }  else {                     flowvars.companylist.add(name);                     return name;                  }             }           </global-functions>      </expression-language>  </configuration> 

in flow, initialize empty array before dataweave.

<set-variable value="#[[]]" variablename="companylist" doc:name="variable" /> 

then, in dataweave, use mel function -

... companyname: getcompanyname($.name) ... 

you can write custom logic in mel function can evaluate name , return value dataweave.