[Resolved] Hi Team, quick question regarding transformers:

add_dataset_tags

What kind of output must my user defined function provide? A str or list of strings leads to errors. Thank you Example:

import logging

import datahub.emitter.mce_builder as builder
from datahub.metadata.schema_classes import (
    DatasetSnapshotClass,
    TagAssociationClass,
)

def custom_tags(current: DatasetSnapshotClass):
    """ Returns tags to associate to a dataset depending on custom logic

    This function receives a DatasetSnapshotClass, performs custom logic and returns
    a list of TagAssociationClass-wrapped tags.

    Args:
        current (DatasetSnapshotClass): Single DatasetSnapshotClass object

    Returns:
        List of TagAssociationClass objects.
    """

    tag_strings = []

    ### Add custom logic here
    tag_strings.append('custom1')
    tag_strings.append('custom2')
    
    tag_strings = [builder.make_tag_urn(tag=n) for n in tag_strings]
    tags = [TagAssociationClass(tag=tag) for tag in tag_strings]
    
    <http://logging.info|logging.info>(f"Tagging dataset {current.urn} with {tag_strings}.")
    return tags

Hi @clean-crayon-15379: it’s not a super ideal interface… but here’s what the contract is:

get_tags_to_add:         Callable[[DatasetSnapshotClass], List[TagAssociationClass]]

Fantastic, thank you very much!

Will be very welcome!!