Apache NiFi Custom processor.

This will help you to learn about how to create apache nifi plugin/processor. You can also leverage the existing controller service in the processor to access the details. In this case I am trying to access AWS authentication service in my custom processor.

Here are the use cases which i have covered in this repo.

1. Using a controller in the custom processor.
2. Sending out multiple responses from the custom processor.

NiFi custom processor

install JAVA and maven

To check the if these are installed run these commands

java -version The version must be 11 or more.

To check the maven installation mvn -version Maven can be latest also.

Now you need to generate the code boilerplate for the custom processors.

1. mvn archetype:generate

2. This will search all available sources. Now it will ask for search. Enter nifi in search to search nifi.

3. Now Once you will select the nifi it will ask for what type of application

4. You need to select between processor or service

5. next step is tell the project name(Artifact base name) - it could be anything like sample

6. Next it will ask the groupId - name that as package name com.org so your project will be .processors.

7. Artifact Id - wil be part of your project artifact id. Which is there in pom.xml

8. Next specify the version for the processor.

9. Next specify name for the project.

10. In last say Yes

Now that will generate the boilerplate code for you.

To build

mvn clean install -Denforcer.skip=true

Deploy

Now a folder would have been generated like nifi-<app-name>-nar

Move inside the folder and then go to target

from this folder you can copy the nar file and then you need to deploy this into the nifi installation directory.

You have 2 options

1. extensions folder where the plugin will be available without the restart.
2. in lib folder you need to restart.

Note - In both cases I had to restart the server.

once the deployment is done your processor will be available in the processor section.

To add log for your custom processors

in nifi folder navigate to conf folder and add this line in bottom. You can define you level of logging here also.

<logger name="com.astuto.processors.cloudwatchLogReader.MetricReader" level="DEBUG"/>

This line you will get in your src/main/resources/META-INF.service/org.apache.nifi.processor.Processor file. At the bottom of this file the path will be there.

com.org.processors.artifact.main