Skip to content

[Bug]: ReadFromCSV does not handle EmptyDataframe well internally #38742

Description

@riana-r

What happened?

Hello,

I am trying to read 50 csv files with 3 columns from a Cloud Dataflow / Apache Beam v2.67.0 job. Previously, I was using ReadFromText, then I wrote a lambda function to split each text line into 3 fields. I tried switching to beam.io.textio.ReadFromCsv (to handle quoted fields for example), but the job randomly fails with the following error :

Image

What I understand is :
ReadFromCsv is reading the data using the Pandas API, which results in 1 or multiple pandas Dataframes. Then it tries to convert each Dataframe into a Beam PCollection. In my case, it seems like an empty Dataframe can be generated sometimes, but the conversion process does not handle it well.

This code here : https://github.com/apache/beam/blob/master/sdks/python/apache_beam/runners/worker/opcounters.py#L221

mean_element_size = self.producer_batch_converter.estimate_byte_size(
       windowed_batch.values) / batch_length

Seems to be the issue, as the batch_length is 0,

The files are not empty of course, they all have around a million lines each

Issue Priority

Priority: 2 (default / most bugs should be filed as P2)

Issue Components

  • Component: Python SDK
  • Component: Java SDK
  • Component: Go SDK
  • Component: Typescript SDK
  • Component: IO connector
  • Component: Beam YAML
  • Component: Beam examples
  • Component: Beam playground
  • Component: Beam katas
  • Component: Website
  • Component: Infrastructure
  • Component: Spark Runner
  • Component: Flink Runner
  • Component: Prism Runner
  • Component: Twister2 Runner
  • Component: Hazelcast Jet Runner
  • Component: Google Cloud Dataflow Runner

Activity

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Metadata

Metadata

Assignees

No one assigned

    Type

    No type

    Projects

    No projects

      Milestone

      No milestone

      Relationships

      None yet

      Development

      No branches or pull requests

      Issue actions