[BEAM-12773] 404 Session not found, when querying Google Cloud Spanner with Python Dataflow.

• Type: Bug
• Status: Open
• Priority: P3
• Resolution: Unresolved
• Affects Version/s: 2.29.0, 2.33.0
• Component/s: io-py-gcp
• Assignee: Unassigned
• Reporter: Reto Egeter
• Created: 18/Aug/21 03:23
• Updated: 04/Jun/22 20:54

Description

My Dataflow copies a SQL table with 230M rows into Cloud Spanner. The initial run is successful, but any subsequent run fails with this error. "h1.google.api_core.exceptions.NotFound: 404 Session not found"
and also "504 Deadline Exceeded"

Here is part of the code:

SPANNER_QUERY = 'SELECT row_id, update_key FROM DomainsCluster2'

spanner_domains = (
      p
      | 'ReadFromSpanner' >> ReadFromSpanner(
          project_id, database, database, sql=SPANNER_QUERY)
      | 'KeyDomainsSpanner' >> beam.Map(_KeyDomainSpanner))

def _KeyDomainSpanner(entity):
  row = {}
  for i, column in enumerate(['row_id', 'update_key']):
    row[column] = entity[i]
  return row['row_id'], row

The Dataflow job is able to read around 10M rows with 2.29.0 but only a few thousand with 2.33.0