thanks for clarifying on getControllerServiceIdentifiers API. I have an other question: If I have a processor that is designed to have on side effect on FlowFile, what is the best/clean way to read content of the flowfile? e.g., my processor’s only job is to log content of FlowFile, is there a method like FlowFile.getContentAsString()? or do I have to do what I am doing here ? https://github.com/xmlking/nifi-websocket/blob/master/src/main/java/com/crossbusiness/nifi/processors/PublishEventBus.java#L102 <https://github.com/xmlking/nifi-websocket/blob/master/src/main/java/com/crossbusiness/nifi/processors/PublishEventBus.java#L102>
Thanks Sumo > On Sep 30, 2015, at 2:52 PM, Aldrin Piri <aldrinp...@gmail.com> wrote: > > Sumo, > > I did some digging around on your Github Repo and see that you've migrated > your ControllerService lookup to your @OnScheduled method, making use of > the ProcessContext. This approach is certainly more preferred in terms of > allowing configuration of the Processor than the prior method you outlined > above. That identifier is the unique ID generated by the framework for a > new controller service. However, to close the trail on the previous path, > from within init, you would have needed to do something along the lines of: > > context.getControllerServiceLookup().getControllerServiceIdentifiers( > VertxServiceInterface.class) > > to find all the instances available and then choose one of those > identifiers, if any were present, at the time the processor was initialized. > > To your second question, I believe you are on the right track, although I > am not overly familiar with Vertx. This seems to map quite closely with > the JMS family of processors (GetJMSTopic [1] in conjunction with its > abstract parent JmsConsumer [2]). If you find you need more granular > control of the session, you can create a Processor that extends > AbstractSessionFactoryProcessor instead of AbstractProcessor. > > Feel free to follow up with any additional questions or details you may > have. > > Thanks! > > [1] > https://github.com/apache/nifi/blob/master/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/GetJMSTopic.java > > <https://github.com/apache/nifi/blob/master/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/GetJMSTopic.java> > [2] > https://github.com/apache/nifi/blob/master/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/JmsConsumer.java > > <https://github.com/apache/nifi/blob/master/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/JmsConsumer.java> > > On Sun, Sep 27, 2015 at 3:24 PM, Sumanth Chinthagunta <xmlk...@gmail.com > <mailto:xmlk...@gmail.com>> > wrote: > >> >> Hi All, >> I am new to NiFi and I'm stuck with couple issues: >> >> 1. Unable to get hold of ControllerService from Processor’s init method. >> I wanted to pre-set some dependencies during init phase instead >> of querying them repeatedly in onTrigger method. >> I am getting null for service and not sure what I have to pass for >> 'serviceIdentifier’ . I couldn't find documentation or examples on how to >> give Identifier to a service. >> >> >> final VertxServiceInterface vertxService = (VertxServiceInterface) >> context.getControllerServiceLookup().getControllerService("VertxService”) >> >> >> https://github.com/xmlking/nifi-websocket/blob/master/src/main/java/com/crossbusiness/nifi/processors/PutEventBus.java#L55 >> < >> https://github.com/xmlking/nifi-websocket/blob/master/src/main/java/com/crossbusiness/nifi/processors/PutEventBus.java#L55 >> >> <https://github.com/xmlking/nifi-websocket/blob/master/src/main/java/com/crossbusiness/nifi/processors/PutEventBus.java#L55> >>> >> >> 2. for my usecase I get data published to a topic from EventBus with >> following code. >> >> EventBus eb = vertx.eventBus(); >> >> eb.consumer("news.uk.sport", message -> { >> System.out.println("I have received a message: " + >> message.body()); >> }); >> >> I am working on a date ingest processor (push based) that needs to >> listen for new messages on a topic and send to flow as FlowFile. >> In my case data source is EvenBus that expose emit messages via >> callback API. >> I am looking for ideas on how to call Processor’s onTrigger method >> when the above callback is evoked. >> Should I have to use my own intermediate queue and poll it in >> onTrigger method? >> is there a better way to trigger the onTrigger method >> programmatically ? >> >> Thanks >> Sumo
