Вы должны установить параметры в элементе parameters модуля сценариев в виде выражения DataWeave.
<flow name="groovy-paramsFlow" >
<http:listener doc:name="Listener" config-ref="HTTP_Listener_config" path="/"/>
<set-variable value="#[123]" doc:name="Set Variable" variableName="myVar"/>
<scripting:execute doc:name="Execute" engine="groovy">
<scripting:code ><![CDATA[def proctext = 'curl -H "apiAccessKeyId: ' + vid + '" -H "apiSecretAccessKey: ' + vpass +'" -H "Accept:application/json" --form "file=@C:\\Files\\test.csv" --form "params={Type:Import}" -X POST http://mysuperserver/media/upload/']]></scripting:code>
<scripting:parameters ><![CDATA[#[{ vid: "abcd", vpass: "efgh" }]
]]></scripting:parameters>
</scripting:execute>
<logger level="INFO" message="Payload #[payload]"/>
</flow>
Output
Payload curl -H "apiAccessKeyId: abcd" -H "apiSecretAccessKey: efgh" -H "Accept:application/json" --form "file=@C:\Files\test.csv" --form "params={Type:Import}" -X POST http://mysuperserver/media/upload/