apache/beam · error · NotImplementedError

{op!r} is not implemented yet. If support for {op!r} is impo

Error message

{op!r} is not implemented yet. If support for {op!r} is important to you, please let the Beam community know by writing to user@beam.apache.org (see https://beam.apache.org/community/contact-us/) or commenting on {issue_url}

What it means

The frame_base.not_implemented/op decorator installs a stub that raises NotImplementedError with guidance to contact the Beam community or comment/vote on the associated tracking issue (BEAM-xxxxx Jira or GitHub issue). It means the pandas method exists in the API surface but has no Beam implementation yet.

Source

Thrown at sdks/python/apache_beam/dataframe/frame_base.py:424

      f":meth:`{_prettify_pandas_type(base_type)}.{name}` is not yet supported "
      f"in the Beam DataFrame API {reason_data['explanation']}")

  if 'url' in reason_data:
    wrapper.__doc__ += f"\n\n For more information see {reason_data['url']}."

  return wrapper


def not_implemented_method(op, issue='20318', base_type=None):
  """Generate a stub method for ``op`` that simply raises a NotImplementedError.

  For internal use only. No backwards compatibility guarantees."""
  assert base_type is not None, "base_type must be specified"
  issue_url = f"https://issues.apache.org/jira/{issue}." if issue.startswith(
      "BEAM-") else f"https://github.com/apache/beam/issues/{issue}"

  def wrapper(*args, **kwargs):
    raise NotImplementedError(
        f"{op!r} is not implemented yet. "
        f"If support for {op!r} is important to you, please let the Beam "
        "community know by writing to user@beam.apache.org "
        "(see https://beam.apache.org/community/contact-us/) or commenting on "
        f"{issue_url}")

  wrapper.__name__ = op
  wrapper.__doc__ = (
      f":meth:`{_prettify_pandas_type(base_type)}.{op}` is not implemented yet "
      "in the Beam DataFrame API.\n\n"
      f"If support for {op!r} is important to you, please let the Beam "
      "community know by `writing to user@beam.apache.org "
      "<https://beam.apache.org/community/contact-us/>`_ or commenting on "
      f"`{issue} <{issue_url}>`_.")

  return wrapper

View on GitHub (pinned to 12126d8942)

Solutions

Implement the equivalent logic with supported dataframe operations or native Beam transforms (map, GroupBy, beam.CombinePerKey).
Materialize to concrete pandas via to_pcollection + pandas and run the method locally.
Track/vote on the issue URL given in the message and upgrade Beam when support lands.
Contribute an implementation upstream if the operation maps to an existing Beam PTransform.

Example fix

// before
result = df.rolling('2s').mean()
// after
# materialize then use pandas, or approximate with Beam windowing:
result = (pcoll | beam.WindowInto(beam.window.Sessions(2))
               | beam.CombinePerKey(beam.combiners.MeanCombineFn()))

Defensive patterns

Strategy: try-catch

Validate before calling

NOT_IMPLEMENTED_OPS = {'resample', 'ewm', 'plot'}
if op_name in NOT_IMPLEMENTED_OPS:
    use_beam_transform_fallback(op_name)

Try / catch

try:
    result = df.resample('1D').mean()
except NotImplementedError:
    result = (pcoll | beam.WindowInto(beam.window.FixedWindows(86400))
                   | beam.CombinePerKey(beam.combiners.MeanCombineFn()))

Prevention

Read the NotImplementedError message: it names the tracking issue and expected support timeline.
Prototype the full dataframe pipeline early to enumerate unsupported methods.
Have a native-Beam fallback plan for each pandas method your port relies on.

When it happens

Trigger: Calling any pandas method registered via the not_implemented(op, issue=...) decorator, e.g. certain resample, rolling, or plotting methods, each carrying its tracking issue URL in the message.

Common situations: Using newer pandas surface area not yet ported to Beam; following pandas tutorials verbatim; encountering methods whose implementation is in progress on the referenced Jira/GitHub issue.

Related errors

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/6d0e5035d141b26e. Report an issue: GitHub.