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  1. Spark
  2. SPARK-19159 PySpark UDF API improvements
  3. SPARK-19165

UserDefinedFunction should verify call arguments and provide readable exception in case of mismatch

    Details

    • Type: Sub-task
    • Status: Resolved
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 1.6.0, 2.0.0, 2.1.0, 2.2.0
    • Fix Version/s: 2.3.0
    • Component/s: PySpark, SQL
    • Labels:
      None

      Description

      Invalid arguments to UDF call fail with a bit cryptic Py4J errors:

      In [5]: g = udf(lambda x: x)
      
      In [6]: df.select(f([]))
      
      ---------------------------------------------------------------------------
      Py4JError                                 Traceback (most recent call last)
      <ipython-input-10-5fb48a5d66d2> in <module>()
      ----> 1 df.select(f([]))
      ....
      Py4JError: An error occurred while calling z:org.apache.spark.sql.functions.col. Trace:
      py4j.Py4JException: Method col([class java.util.ArrayList]) does not exist
      	at py4j.reflection.ReflectionEngine.getMethod(ReflectionEngine.java:318)
      	at py4j.reflection.ReflectionEngine.getMethod(ReflectionEngine.java:339)
      	at py4j.Gateway.invoke(Gateway.java:274)
      	at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
      	at py4j.commands.CallCommand.execute(CallCommand.java:79)
      	at py4j.GatewayConnection.run(GatewayConnection.java:214)
      	at java.lang.Thread.run(Thread.java:745)
      
      

      It is pretty easy to perform basic input validation:

      In [8]: f = udf(lambda x: x)
      
      In [9]: f(1)
      ---------------------------------------------------------------------------
      TypeError                                 Traceback (most recent call last)
      
      ...
      TypeError: All arguments should be Columns or strings representing column names. Got 1 of type <class 'int'>
      
      

      This can be further extended to check for expected number of arguments or even, with some type of annotations, SQL types.

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            • Assignee:
              hyukjin.kwon Hyukjin Kwon
              Reporter:
              zero323 Maciej Szymkiewicz
            • Votes:
              1 Vote for this issue
              Watchers:
              4 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: