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Debugging a PySpark Pipeline
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Debugging a PySpark Pipeline

MediumPython

Problem

Can you walk through your process for debugging a complex PySpark pipeline? For the coding portion, implement first_bad_stage(stage_outputs, required_fields). stage_outputs is an ordered array of stage objects, each containing a name and output rows; required_fields maps each stage name to required field names. Return [stage_index, row_index] for the first row that is missing a required field or contains a null value, scanning stages and rows in order, or [-1, -1] when all outputs are valid.

Constraints

  • 1 <= stage_outputs.length <= 10^4
  • Each stage name is unique
  • Each stage contains zero or more row objects
  • Each required field name is a string
  • A row is valid when every required field exists and has a non-null value

Function Signature

def first_bad_stage(stage_outputs, required_fields):
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