@janapati10  Oh, too bad, this options for manipulating JSON with Expression Language are - as far as I know - not available before 1.10.0.   When the JSON-format is really stabil maybe this will work for you. UpdateAttribute ==> ${FF_CONTENT:substringBefore('['):append('["'):append(${callid}):append('"]'):append(${FF_CONTENT:substringAfter(']')})}   It is not "elegant" but I haven't got another idea, sorry. ... View more

NiFi 2.11 ? I must have missed something... Let's assume it is 1.11.0 then the used function should be available.   I think there is a typo in your Expression Language. ${FF_CONTENT:jsonPathAdd('$.linkedData', ${callid})} There has to be a dot between $ and linkedData. ... View more

Maybe you want to try this way. Worked on 1.10.0 ... View more

@janapati10  For me your question is to abstract, sorry. Could you show some of your data? Are we talking about JSON-array? If so and you are already using NiFi 1.10.0 there are some new options in expression language to manipulate JSON. ... View more

@mburgess  Matt, thank you so much for your quick response and help. It took me some time to figure out what you meant... but it works like a charm!   If anyone can use the solution, here it is: //====================================================================================================== // TEST java LocalDate.parse with groovy max-function // FF-Attribute RESPONSE contains [{"id":"(1208)", "datbis":"20180219" }, { "id":"(1210)", "datbis":"20191231" }, { "id":"(1212)", "datbis":"20200128" }] // FF-Atribute MAX_datbis returns 20200128 //====================================================================================================== import java.time.LocalDate def flowFile = session.get() if(!flowFile) return try { def objList = new groovy.json.JsonSlurper().parseText(flowFile.getAttribute('RESPONSE')) def max = objList.max {LocalDate.parse(it.datbis,"yyyyMMdd")} flowFile = session.putAttribute(flowFile, 'MAX_datbis', max.datbis.toString()) session.transfer(flowFile, REL_SUCCESS) } catch(e) { log.error("Error while determining max", e) session.transfer(flowFile, REL_FAILURE) } ... View more

@mburgess Hi Matt, your help is needed urgently. The script that reads a JSON structure from an attribute and determines the maximum value of the date worked fine. I haven't worked on the flow for a while and now it doesn't work anymore. In the meantime there was only an update from 1.9.2 to 1.10.0. Otherwise everything is as before. Since I still have no idea about Groovy, I can't fix the error. Please, could you help me again? Thanks.  This is content of attribute RESPONSE [ {"id":"(1208)", "datbis":"20190630" }, { "id":"(1210)", "datbis":"20191231" } ] ERROR   ExecuteScript[id=e70ffcf5-016f-1000-0000-000063865879] Error while determining max: groovy.lang.MissingMethodException: No signature of method: static java.util.Date.parse() is applicable for argument types: (String, String) values: [yyyyMMdd, 20190630] Possible solutions: parse(java.lang.String), wait(), clone(), any(), grep(), use(java.lang.Class, groovy.lang.Closure)​   ... View more

@MattWho  Thanks for this information. I haven't yet updated the registry because I can't do this myself. As soon as the update will be made sometime I will have a look on this an give you a reply. ... View more

@MattWho  refering to nifi-registry-bootstrap.log we use v0.3.0   But I'm pretty sure that I didn't watch this behaviour before using NiFi 1.10.0 (former version 1.9.2). Can you confirm this connection with the NiFi version?   Thanks! ... View more

@stevenmatison  Thanks for this information. Haven't found a hint to this problem.   1.10 is not ready for “production”... In terms of parameter handling or what does this mean? ... View more