Hi Matt, thanks! as you said the AbstractRecordProcessor was the missing bits to get me started. There is one more question thou that I would like to learn: how to create/manipulate schemas on the fly. Scouting some tests I saw how to create a new basic schema but I would like to understand how to create a new schema from a given pojo object, and how to add strcut attributes in a existing schema.
By the way I'm testing and cleaning my invokedscriptprocessor used to enhance data with multiples sql lookups, and I intent to share it here with all. If you want you can share it on you blog too. Cheers, Eric 2017-11-22 19:28 GMT-02:00 Matt Burgess <mattyb...@apache.org>: > Eric, > > If you're looking for examples on implementing a scripted record > reader/writer, you can see the unit test examples [1] or Drew Lim's > blog [2]. However I suspect you are looking to leverage an existing > RecordReader/Writer from a scripted processor such as ExecuteScript or > InvokeScriptedProcessor, to prototype a "record-aware" processor. A > general approach is implemented in AbstractRecordProcessor[3], I don't > believe the NiFi Scripting NAR has access to that class, but you can > certainly copy-and-paste the relevant bits of code. I don't think you > can (easily) get access to an existing RecordReader/Writer controller > service, but Mark Payne outlined the alternative in your mailing list > question about getting a DBCPService property. The recommended > approach is to use InvokeScriptedProcessor and specify your own > RecordReader/Writer properties which will be presented to the user in > the InvokeScriptedProcessor dialog (once the script has been applied). > Then you can get the RecordReader/Writer objects (see [3] lines > 100-101) and use them in a similar way as [3]. > > This (and the answer(s) to your questions in the other mailing list > post) would make excellent blog posts/articles, I hope to do some > relatively soon, will keep the list posted :) > > Regards, > Matt > > [1] https://github.com/apache/nifi/tree/master/nifi-nar- > bundles/nifi-scripting-bundle/nifi-scripting-processors/src/ > test/resources/groovy > [2] https://community.hortonworks.com/articles/115311/convert- > csv-to-json-avro-xml-using-convertrecord-p.html > [3] https://github.com/apache/nifi/blob/master/nifi-nar- > bundles/nifi-standard-bundle/nifi-standard-processors/src/ > main/java/org/apache/nifi/processors/standard/ > AbstractRecordProcessor.java#L94 > > > On Wed, Nov 22, 2017 at 3:00 PM, Eric Chaves <e...@uolet.com> wrote: > > Hi folks, > > > > Due to my lack of knowledge with Avro in my scripted processors I'm > required > > to convert them to JSON in order to be able to manipulate them. > > > > I would like to avoid this and write record based processors but I have > no > > clue about how should I do to actually read/write/modify record based > > content (including modifying underlying schemas). > > > > Do you have any reading material to recommend? > > > > Thanks in advance, > > > > Eric >
