[tor-commits] [stem/master] Skip empty files in descriptor tarballs

[atagar at torproject.org]

commit 0ce10154e9686f22deed58b6e627283bde9677a3
Author: Damian Johnson <atagar at torproject.org>
Date:   Fri Jan 15 10:00:34 2016 -0800

    Skip empty files in descriptor tarballs
    
    While reading a descriptor tarball from CollecTor we choked due to an empty file...
    
      Traceback (most recent call last):
        File "metrics.py", line 81, in <module>
          measure_average_advertised_bandwidth('/home/atagar/Desktop/server-descriptors-2015-11.tar')
        File "metrics.py", line 9, in measure_average_advertised_bandwidth
          for desc in parse_file(path):
        File "/home/atagar/Desktop/stem/stem/descriptor/__init__.py", line 171, in parse_file
          for desc in handler(descriptor_file, descriptor_type, validate, document_handler, **kwargs):
        File "/home/atagar/Desktop/stem/stem/descriptor/__init__.py", line 246, in _parse_file_for_tar_path
          for desc in parse_file(tar_file, *args, **kwargs):
        File "/home/atagar/Desktop/stem/stem/descriptor/__init__.py", line 171, in parse_file
          for desc in handler(descriptor_file, descriptor_type, validate, document_handler, **kwargs):
        File "/home/atagar/Desktop/stem/stem/descriptor/__init__.py", line 261, in _parse_file_for_tarfile
          for desc in parse_file(entry, *args, **kwargs):
        File "/home/atagar/Desktop/stem/stem/descriptor/__init__.py", line 228, in parse_file
          for desc in parse(descriptor_file):
        File "/home/atagar/Desktop/stem/stem/descriptor/__init__.py", line 226, in parse
          raise TypeError("Unable to determine the descriptor's type. filename: '%s', first line: '%s'" % (filename, first_line))
      TypeError: Unable to determine the descriptor's type. filename: 'f4b03227e12be3353af32761cbd25a62afb9ea42', first line: ''
    
    In particular this was from...
    
      server-descriptors-2015-11/f/4/f4b03227e12be3353af32761cbd25a62afb9ea42
    
    Not sure if this is a problem or not on CollecTor's end but making us a little
    more resilient by skipping empty files in tarballs.
---
 stem/descriptor/__init__.py |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/stem/descriptor/__init__.py b/stem/descriptor/__init__.py
index a2877c8..6b18d65 100644
--- a/stem/descriptor/__init__.py
+++ b/stem/descriptor/__init__.py
@@ -256,6 +256,9 @@ def _parse_file_for_tarfile(descriptor_file, *args, **kwargs):
     if tar_entry.isfile():
       entry = descriptor_file.extractfile(tar_entry)
 
+      if entry.size == 0:
+        continue
+
       try:
         for desc in parse_file(entry, *args, **kwargs):
           desc._set_archive_path(entry.name)