[tor-commits] [stem/master] Don't raise a ValueError when descriptor information is unavialable

[atagar at torproject.org]

commit ce2d809ae979aad67d626437078f3a639597f9a6
Author: Damian Johnson <atagar at torproject.org>
Date:   Mon Nov 24 11:24:34 2014 -0800

    Don't raise a ValueError when descriptor information is unavialable
    
    Controller methods like get_network_status() raised a ValueError and pretty
    unhelpful error message when descriptor information is unavailable...
    
      ======================================================================
      ERROR: test_get_network_status
      ----------------------------------------------------------------------
      Traceback (most recent call last):
        File "/home/atagar/Desktop/stem/test/integ/control/controller.py", line 1108, in test_get_network_status
          self.assertRaises(stem.ControllerError, controller.get_network_status, 'blargg')
        File "/usr/lib/python2.7/unittest/case.py", line 471, in assertRaises
          callableObj(*args, **kwargs)
        File "/home/atagar/Desktop/stem/stem/control.py", line 384, in wrapped
          raise exc
      ValueError: Router status entries (v3) must have a 'r' line:
    
    I don't have a reliable repro for this, but I've seen it on occasion. We're not
    documented as raising ValueErrors, so raising a ControllerError instead with a
    slightly more descriptive message.
---
 stem/control.py |   21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/stem/control.py b/stem/control.py
index 6e34ec0..1079629 100644
--- a/stem/control.py
+++ b/stem/control.py
@@ -1454,6 +1454,10 @@ class Controller(BaseController):
       raise ValueError("'%s' isn't a valid fingerprint or nickname" % relay)
 
     desc_content = self.get_info(query, get_bytes = True)
+
+    if not desc_content:
+      raise stem.ControllerError("Descriptor information is unavailable, tor might still be downloading it")
+
     return stem.descriptor.microdescriptor.Microdescriptor(desc_content)
 
   @with_default(yields = True)
@@ -1546,6 +1550,10 @@ class Controller(BaseController):
         raise ValueError("'%s' isn't a valid fingerprint or nickname" % relay)
 
       desc_content = self.get_info(query, get_bytes = True)
+
+      if not desc_content:
+        raise stem.ControllerError("Descriptor information is unavailable, tor might still be downloading it")
+
       return stem.descriptor.server_descriptor.RelayDescriptor(desc_content)
     except Exception as exc:
       if not self._is_server_descriptors_available():
@@ -1581,8 +1589,11 @@ class Controller(BaseController):
 
     desc_content = self.get_info('desc/all-recent', get_bytes = True)
 
-    if not desc_content and not self._is_server_descriptors_available():
-      raise ValueError(SERVER_DESCRIPTORS_UNSUPPORTED)
+    if not desc_content:
+      if not self._is_server_descriptors_available():
+        raise stem.ControllerError(SERVER_DESCRIPTORS_UNSUPPORTED)
+      else:
+        raise stem.ControllerError("Descriptor information is unavailable, tor might still be downloading it")
 
     for desc in stem.descriptor.server_descriptor._parse_file(io.BytesIO(desc_content)):
       yield desc
@@ -1655,6 +1666,9 @@ class Controller(BaseController):
 
     desc_content = self.get_info(query, get_bytes = True)
 
+    if not desc_content:
+      raise stem.ControllerError("Descriptor information is unavailable, tor might still be downloading it")
+
     if self.get_conf('UseMicrodescriptors', '0') == '1':
       return stem.descriptor.router_status_entry.RouterStatusEntryMicroV3(desc_content)
     else:
@@ -1699,6 +1713,9 @@ class Controller(BaseController):
 
     desc_content = self.get_info('ns/all', get_bytes = True)
 
+    if not desc_content:
+      raise stem.ControllerError("Descriptor information is unavailable, tor might still be downloading it")
+
     desc_iterator = stem.descriptor.router_status_entry._parse_file(
       io.BytesIO(desc_content),
       True,