RecordTransformResult

Class nifiapi.recordtransform.RecordTransformResult

Parameters

Name	Type	Description
relationship	String; Default 'success'	Name of the relationship the FlowFile should be routed to
record	Dictionary	A JSON-serializable dictionary representing the transformed record.
schema	RecordSchema; Default None	An instance of Java class implementing the org.apache.nifi.serialization.record.RecordSchema interface
partition	Map<String, Object>	An instance of HashMap<partition-name, transformed-record>

partition

The partition parameter is used to define how records are grouped when writing to an output destination. This parameter allows users to specify a partitioning strategy, such as by a specific field or set of fields, which can help organize data into separate files based on the partitioning criteria.

info

Note that the expected value of the partition parameter is an instance of a Java HashMap.

e.g.:

from nifiapi.__jvm__ import JvmHolder
from nifiapi.recordtransform import (
    RecordTransform,
    RecordTransformResult
)
from nifiapi.properties import ProcessContext
from random import randint


class Processor(RecordTransform):
    (...)

    def __init__(self, *args, **kwargs):
        super().__init__()
        self.hash_map = JvmHolder.jvm.java.util.HashMap

    def transform(
        self, context: ProcessContext, record, schema, attribute_map
    ) -> RecordTransformResult:
        '''
        The following example will randomly partition incoming records
        into two sets: 'partition-0' and 'partition-1'.

        Parameters:
            context (ProcessContext)
            record (Mixed)
            schema (org.apache.nifi.serialization.record.RecordSchema)
            attribute_map (CachingAttributeMap)

        Returns:
            RecordTransformResult
        '''
        partition = self.hash_map()

        n = randint(0, 1)
        # Add a partitioning criterion 'random'
        partition["random"] = f"partition-{n}"

        return RecordTransformResult(
            relationship="success",
            record=record,
            partition=partition
        )