Brian, The NAR dependency stuff all breaks down to providing classpath isolation and not polluting the classpath of downstream NARs with dependencies required for Controller Service implementation. We try to keep Controller Service interfaces lean by not depending on external libs in the interface (generally a good practice anyways). Both the implementation of the Controller Service and the any Processor NAR that want to consume the Controller Service needs to depend on the Controller Service API NAR (where the interface lives). This established a common parent ClassLoader which allows the service to be access across NARs. If your building Processor NARs that depend on custom Controller Services and standard Controller Services, you'll want to have your custom Controller Services API NAR depend on the standard Controller Services API NAR. The NAR dependency tree (if you will) maps to a ClassLoader hierarchy within NiFi.
Controller Services being added in a disabled state is remaining consistent with Processors (and other components) in template. Also, because sensitive properties are not included in templates, they may require the user to complete the configuration prior to enabling. Matt On Fri, Aug 14, 2015 at 8:01 AM, Brian Ghigiarelli <[email protected]> wrote: > Bryan, > > Thank you!! Adding a NAR dependency to my standard-processors NAR did the > trick to get NiFi to recognize the service for these processors and > auto-create a new instance of the Controller Service on template import. I > owe ya a beer or six the next time our paths cross. > > How did you figure out the required NAR dependency? Any great debugging > tricks to share, or was it your existing depth of NiFi knowledge that led > you to that solution? > > As a follow-on to that, I'm seeing that Controller Services created via > Template instantiation are created in "Disabled" state. Is that expected? > Is there any way to drag-and-drop a template with controller services onto > a canvas and have the newly created controller services enabled? > > Thanks again, > Brian > > On Thu, Aug 13, 2015 at 5:57 PM, Bryan Bende <[email protected]> wrote: > > > Brian, > > > > I just ran into this exact scenario today while testing a custom > controller > > service. > > > > The cause of the problem was that my custom service NAR, did not have a > NAR > > dependency on the service API NAR because I had accidentally marked the > API > > NAR as provided in the pom file. Once I removed the provided scope > > everything worked. > > > > You can check the MANIFEST file in your custom service NAR... under your > > NIFI_HOME/work/nar/extensions/{your-nar}/META-INF/MANIFEST.MF it should > > have a "Nar-Dependency-Id" on your API NAR. If it is missing that, that > is > > likely the problem. > > > > -Bryan > > > > > > > > On Thu, Aug 13, 2015 at 5:22 PM, Brian Ghigiarelli <[email protected]> > > wrote: > > > > > NiFi Gurus, > > > > > > Regarding Controller Services, I'm seeing some strange behavior > > regarding a > > > custom Controller Service only showing its ID in a Processor and was > > > wondering if anyone's encountered similar issues. Seeing this on the > > > latest develop branch, 0.3.0-SNAPSHOT. > > > > > > Steps taken: > > > 1. Create instance of Controller Service in the Controller Settings > > > > Controller Services tab > > > 1a. Enable that instance of the Controller Service > > > 2. Add new Processor on canvas that will use Controller Service > > > 3. Configure Processor > > > 3a. Existing Controller Service does not show in property options. Only > > "No > > > value" and "Create new service..." > > > 3b. Clicking "Create new service..." opens modal with the custom > > Controller > > > Service as the only item in the dropdown > > > 3c. Clicking "Create" button succeeds, but puts the UUID of the > > Controller > > > Service in the Value of the Processor Property. > > > > > > Observed state: > > > - Processor is still invalid > > > - The ID in the Processor Property matches the ID of the second > > (disabled) > > > instance of the Controller Service in the Controller Settings modal. > > > > > > There are no errors in nifi-app.log - only contains log messages from > the > > > StandardControllerServiceProvider that it "Created Controller Service > of > > > type [my-implementation-class] with identifier > > > [UUID-that-shows-in-the-GUI]" > > > > > > Adding a DetectDuplicate processor with the > > > DistributedMapCacheClientService works just fine, so it'd hard to point > > > fingers at the framework. Any thoughts on where to begin debugging > > and/or > > > loggers to turn up would be greatly appreciated! > > > > > > Thanks, > > > Brian > > > > > > > > > -- > Brian Ghigiarelli > 570-878-9139 >
