1.4.1 - Catch NXDOMAIN, plus travis install iputils-ping

Plus check for 'network is unreachable' when pinging, because travis-ci doesn't like IPv6...

Raise a warning if test_ping / test_ping_v6 fails due to NetworkUnreachable, to avoid full test suite
failure due to lack of IPv4 / IPv6

Author: Someguy123

.travis.yml

@@ -10,6 +10,9 @@ python:
   - "3.7-dev"
   - "3.8-dev"
   - "nightly"
+before_install:
+  - sudo apt-get update -qy
+  - sudo apt-get install -qy iputils-ping
 install:
   - pip install -r docs/requirements.txt
   - pip install .

privex/helpers/__init__.py

@@ -83,7 +83,7 @@ def _setup_logging(level=logging.WARNING):
 log = _setup_logging()
 name = 'helpers'
 
-VERSION = '1.4.0'
+VERSION = '1.4.1'
 
 
 

privex/helpers/exceptions.py

@@ -98,3 +98,11 @@ class NotConfigured(PrivexException):
     
     Example: Attempting to use a database dependant function/method without having configured any database details.
     """
+
+
+class NetworkUnreachable(PrivexException):
+    """
+    Thrown when a network interface or IP version (e.g. IPv4/v6) is unavailable.
+    
+    Example: when running ``ping`` with an IPv6 address on a system which has no IPv6.
+    """

privex/helpers/net.py

@@ -40,15 +40,15 @@
 import logging
 import platform
 import subprocess
-from privex.helpers.exceptions import BoundaryException
+from privex.helpers.exceptions import BoundaryException, NetworkUnreachable
 from privex.helpers import plugin
 from ipaddress import ip_address, IPv4Address, IPv6Address
 from typing import Union
 
 log = logging.getLogger(__name__)
 
 try:
-    from dns.resolver import Resolver, NoAnswer
+    from dns.resolver import Resolver, NoAnswer, NXDOMAIN
 
     def asn_to_name(as_number: Union[int, str], quiet: bool = True) -> str:
         """
@@ -83,7 +83,7 @@ def asn_to_name(as_number: Union[int, str], quiet: bool = True) -> str:
                 asname = str(res[0]).strip('"').split('|')[-1:][0].strip()
                 return str(asname)
             raise NoAnswer('privex.helpers.net.asn_to_name returned no results.')
-        except NoAnswer:
+        except (NoAnswer, NXDOMAIN):
             if quiet:
                 return 'Unknown ASN'
             raise KeyError('ASN {} was not found, or server did not respond.'.format(as_number))
@@ -262,5 +262,10 @@ def ping(ip: str, timeout: int = 30) -> bool:
     if platform.system() not in opts:
         raise NotImplementedError(f"{__name__}.ping is not fully supported on platform '{platform.system()}'...")
 
-    with subprocess.Popen(opts[platform.system()] + [ip], stdout=subprocess.PIPE) as proc:
-        return 'bytes from {}'.format(ip) in proc.stdout.read().decode('utf-8')
+    with subprocess.Popen(opts[platform.system()] + [ip], stdout=subprocess.PIPE, stderr=subprocess.PIPE) as proc:
+        out, err = proc.communicate()
+        err = err.decode('utf-8')
+        if 'network is unreachable' in err.lower():
+            raise NetworkUnreachable(f'Got error from ping: "{err}"')
+        
+        return 'bytes from {}'.format(ip) in out.decode('utf-8')

tests/test_general.py

@@ -42,7 +42,7 @@
 import warnings
 
 from privex import helpers
-from privex.helpers import ping
+from privex.helpers import ping, NetworkUnreachable
 from tests.base import PrivexBaseCase
 
 
@@ -66,6 +66,9 @@ def test_ping(self):
         except NotImplementedError as e:
             warnings.warn(f"Skipping test TestGeneral.test_ping as platform is not supported: {str(e)}")
             return
+        except NetworkUnreachable as e:
+            warnings.warn(f"Skipping test TestGeneral.test_ping as network is unavailable: \"{str(e)}\"")
+            return
 
     def test_ping_v6(self):
         """Test success & failure cases for ping function with IPv6, as well as input validation"""
@@ -81,6 +84,9 @@ def test_ping_v6(self):
         except NotImplementedError as e:
             warnings.warn(f"Skipping test TestGeneral.test_ping_v6 as platform is not supported: \"{str(e)}\"")
             return
+        except NetworkUnreachable as e:
+            warnings.warn(f"Skipping test TestGeneral.test_ping_v6 as network is unavailable: \"{str(e)}\"")
+            return
 
     def _check_asn(self, asn, expected_name):
         if not helpers.plugin.HAS_DNSPYTHON: