About FlowFileTransformResult

Class nifiapi.flowfiletransform.FlowFileTransformResult

The FlowFileTransformResult class provides an interface for extending and modifying attributes and content of a FlowFile, as well as define the outgoing relationship.

Parameters

Name	Type	Description
relationship	String	Name of the relationship the FlowFile should be routed to
attributes	Dictionary; Default None	A key-value pairs representing modified FlowFile attributes
contents	Byte Array or String; Default None	Content of the FlowFile

e.g:

return FlowFileTransformResult(
    'success',
    attributes={},
    contents=None
)

Modifying FlowFile attributes

The FlowFileTransformResult provides an interface to add or modify existing FlowFile attributes.

important

Note that all attributes must be represented as strings.

from nifiapi.flowfiletransform import (
    FlowFileTransform,
    FlowFileTransformResult,
)
from nifiapi.properties import ProcessContext


class Processor(FlowFileTransform):
    (...)

    def transform(
        self, context: ProcessContext, flow_file
    ) -> FlowFileTransformResult:
        '''
        Parameters:
            context (ProcessContext)
            flow_file

        Returns:
            FlowFileTransformResult
        '''
        return FlowFileTransformResult('success', attributes={
            "new_attribute": str(1234)
        })

Modifying FlowFile content

You can modify the contents of a FlowFile through the FlowFileTransformResult. Simply pass a new value in the contents parameter:

important

Note that the new content must be either a Byte Array or String type.

from nifiapi.flowfiletransform import (
    FlowFileTransform,
    FlowFileTransformResult,
)
from nifiapi.properties import ProcessContext


class Processor(FlowFileTransform):
    (...)

    def transform(
        self, context: ProcessContext, flow_file
    ) -> FlowFileTransformResult:
        '''
        Parameters:
            context (ProcessContext)
            flow_file

        Returns:
            FlowFileTransformResult
        '''
        return FlowFileTransformResult('success', contents="New content")