कैसे अपने स्वयं के प्रोसेसर लिखने या NiFi में कार्यक्षमता का विस्तार करने के लिए

ExecuteScript

flowFile = session.get() 
if(!flowFile) return

flowFile = session.create()
// Additional processing here

flowFile = session.get() 
if(!flowFile) return
flowFile = session.putAttribute(flowFile, 'myAttr', 'myValue')

flowFile = session.get() if(!flowFile) return
flowFile.getAttributes().each { key,value ->
// Do something with the key/value pair
}

log.info('Found these things: {} {} {}', ['Hello',1,true] as Object[])

ExecuteGroovyScript

RecordWriter          HashMap<String,RecordSetWriterFactory>
RecordReader         HashMap<String,RecordReaderFactory>
SQL                       HashMap<String,groovy.sql.Sql> 
CTL                       HashMap<String,ControllerService>

import org.apache.nifi.processor.ProcessContext
...
static onStart(ProcessContext context){
// your code
}
static onStop(ProcessContext context){
// your code
}
REL_SUCCESS << flowFile

InvokeScriptedProcessor

class GroovyProcessor implements Processor {
          @Override
          void initialize(ProcessorInitializationContext context) { log = context.getLogger()
          }

          @Override
          void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) thr

          @Override
          Collection<ValidationResult> validate(ValidationContext context) { return null 

          @Override
          PropertyDescriptor getPropertyDescriptor(String name) { return null	}

          @Override
          void onPropertyModified(PropertyDescriptor descriptor, String oldValue, String n

          @Override
          List<PropertyDescriptor> getPropertyDescriptors() { return null }

          @Override
          String getIdentifier() { return null }
}

 @Override
void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) throw s ProcessException {
            final ProcessSession session = sessionFactory.createSession(); def 
            flowFile = session.create()
           if (!flowFile) return
                 // your code
           try 
                 { session.commit();
           } catch (final Throwable t) { 
                 session.rollback(true); 
                 throw t;
           }
}

abstract void executeScript(ProcessContext context, ProcessSession session)

void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory)

import org.apache.nifi.components.PropertyDescriptor import org.apache.nifi.components.ValidationContext import org.apache.nifi.components.ValidationResult import org.apache.nifi.logging.ComponentLog
import org.apache.nifi.processor.ProcessContext import org.apache.nifi.processor.ProcessSession
import org.apache.nifi.processor.ProcessSessionFactory import org.apache.nifi.processor.Processor
import org.apache.nifi.processor.ProcessorInitializationContext import org.apache.nifi.processor.Relationship
import org.apache.nifi.processor.exception.ProcessException 

abstract class BaseGroovyProcessor implements Processor {

	public ComponentLog log

	public Set<Relationship> relationships; 

	@Override
	void initialize(ProcessorInitializationContext context) { log = context.getLogger()
	}

	@Override
	void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) thr final ProcessSession session = sessionFactory.createSession();
	try {
		executeScript(context, session); 
		session.commit();
	} catch (final Throwable t) { 
		session.rollback(true); 
		throw t;
	}
}

	abstract void executeScript(ProcessContext context, ProcessSession session) thro

	@Override
	Collection<ValidationResult> validate(ValidationContext context) { return null }

	@Override
	PropertyDescriptor getPropertyDescriptor(String name) { return null	} 

	@Override
	void onPropertyModified(PropertyDescriptor descriptor, String oldValue, String n

	@Override
	List<PropertyDescriptor> getPropertyDescriptors() { return null }
	
	@Override
	String getIdentifier() { return null }

}

import org.apache.commons.lang3.tuple.Pair
import org.apache.nifi.expression.ExpressionLanguageScope import org.apache.nifi.processor.util.StandardValidators import ru.rt.nifi.common.BaseGroovyProcessor

import org.apache.nifi.components.PropertyDescriptor import org.apache.nifi.dbcp.DBCPService
import org.apache.nifi.processor.ProcessContext import org.apache.nifi.processor.ProcessSession
import org.apache.nifi.processor.exception.ProcessException import org.quartz.CronExpression

import java.sql.Connection
import java.sql.PreparedStatement import java.sql.ResultSet
import java.sql.SQLException import java.sql.Statement

class InvokeScripted extends BaseGroovyProcessor {
	public static final REL_SUCCESS = new Relationship.Builder()
		.name("success")
		.description("If the cache was successfully communicated with it will be rou
		.build()

	public static final REL_FAILURE = new Relationship.Builder()
		.name("failure")
		.description("If unable to communicate with the cache or if the cache entry
		.build()

	@Override
	void executeScript(ProcessContext context, ProcessSession session) throws Proces 	def flowFile = session.create()
		if (!flowFile) return

		try {
				// your code

			session.transfer(flowFile, REL_SUCCESS)
		} catch(ProcessException | SQLException e) { 
			session.transfer(flowFile, REL_FAILURE)
			log.error("Unable to execute SQL select query {} due to {}. No FlowFile
		}
	}
}

निष्कर्ष