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#     http://www.apache.org/licenses/LICENSE-2.0
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from nifiapi.flowfiletransform import FlowFileTransform, FlowFileTransformResult


class RotatingForwarder(FlowFileTransform):
    """
    Forwards flow files to a different relationship each time it is called in a round robin manner.
    """
    def __init__(self, **kwargs):
        self.relationship_index = 0
        self.relationships = ["first", "second", "third", "fourth"]

    def transform(self, context, flowFile):
        content = flowFile.getContentsAsBytes().decode()

        relationship = self.relationships[self.relationship_index % len(self.relationships)]
        self.relationship_index += 1
        self.relationship_index %= len(self.relationships)
        return FlowFileTransformResult(relationship, contents=content)