[ARROW-5374] [Python] Misleading error message when calling pyarrow.read_record_batch on a complete IPC stream

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.15.0
• Component/s: Python
• Labels: beginner pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/21833
• Assignee: Wes McKinney
• Reporter: Antoine Pitrou
• Created: 20/May/19 09:50
• Updated: 11/Jan/23 07:40
• Resolved: 09/Sep/19 14:38

Description

>>> batch = pa.RecordBatch.from_arrays([pa.array([b"foo"], type=pa.utf8())], names=['strs'])                                                                   
>>> stream = pa.BufferOutputStream()
>>> writer = pa.RecordBatchStreamWriter(stream, batch.schema)
>>> writer.write_batch(batch)                                                                                                                                  
>>> writer.close()                                                                                                                                             
>>> buf = stream.getvalue()                                                                                                                                    
>>> pa.read_record_batch(buf, batch.schema)                                                                                                                    
Traceback (most recent call last):
  File "<ipython-input-31-4f168f453f3a>", line 1, in <module>
    pa.read_record_batch(buf, batch.schema)
  File "pyarrow/ipc.pxi", line 583, in pyarrow.lib.read_record_batch
    check_status(ReadRecordBatch(deref(message.message.get()),
  File "pyarrow/error.pxi", line 87, in pyarrow.lib.check_status
    raise ArrowIOError(message)
ArrowIOError: Expected IPC message of type schema got record batch

Issue Links

• links to: GitHub Pull Request #5313