[AVRO-1741] Python 3 code should check if avro.codec is None before decoding

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.7.7, 1.8.2
• Assignee: Matthew Hayes
• Reporter: Matthew Hayes
• Created: 15/Sep/15 23:27
• Updated: 25/Oct/19 20:01
• Resolved: 20/Dec/18 20:29

Description

I'm getting the error below when trying to read an Avro file in Python 3. FWIW, I generated this Avro file from Pig. I don't know if that makes a difference.

avro.datafile.DataFileReader(open("test.avro","rb"),avro.io.DatumReader())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/mhayes/.pyenv/versions/3.4.2/lib/python3.4/site-packages/avro/datafile.py", line 352, in __init__
    self.codec = self.GetMeta('avro.codec').decode('utf-8')
AttributeError: 'NoneType' object has no attribute 'decode'

It appears the problem is in the following code. It should check if GetMeta returns None before trying to decode it. The Python 2 code doesn't have this problem because it is already decoded.

    # ensure codec is valid
    self.codec = self.GetMeta('avro.codec').decode('utf-8')
    if self.codec is None:
      self.codec = "null"
    if self.codec not in VALID_CODECS:
      raise DataFileException('Unknown codec: %s.' % self.codec)