Sync charm-helpers

Change-Id: I7160ad3ac03c844f95352ba69c1139ba9005755e
Signed-off-by: Felipe Reyes <felipe.reyes@canonical.com>

charmhelpers/contrib/network/ip.py

@@ -134,6 +134,8 @@ def get_address_in_network(network, fallback=None, fatal=False):
 
 def is_ipv6(address):
     """Determine whether provided address is IPv6 or not."""
+    if not address:
+        return False
     try:
         address = netaddr.IPAddress(address)
     except netaddr.AddrFormatError:
@@ -467,9 +469,21 @@ def ns_query(address):
         return None
 
     try:
-        answers = dns.resolver.query(address, rtype)
+        resolv = dns.resolver.Resolver()
+        # The dnspython library sets a default DNS query lifetime of 5.0 seconds,
+        # as defined in BaseResolver.reset() (see https://github.com/rthalley/
+        # dnspython/blob/7ed1648b/dns/resolver.py#L709, commit 7ed1648b).
+        resolv.lifetime = config('dns-query-timeout') or 5.0
+        if hasattr(resolv, 'resolve'):
+            answers = resolv.resolve(address, rtype)
+        else:
+            answers = resolv.query(address, rtype)
     except (dns.resolver.NXDOMAIN, dns.resolver.NoNameservers):
         return None
+    except dns.exception.Timeout:
+        log("DNS query timed out for address {} with rtype {} and timeout "
+            "{}".format(address, rtype, resolv.lifetime), level=WARNING)
+        return None
 
     if answers:
         return str(answers[0])
@@ -618,7 +632,7 @@ def get_relation_ip(interface, cidr_network=None):
         # Currently IPv6 has priority, eventually we want IPv6 to just be
         # another network space.
         assert_charm_supports_ipv6()
-        return get_ipv6_addr()[0]
+        return get_ipv6_addr(dynamic_only=False)[0]
     elif cidr_network:
         # If a specific CIDR network is passed get the address from that
         # network.

charmhelpers/contrib/openstack/context.py

@@ -25,7 +25,10 @@ import socket
 import time
 
 from base64 import b64decode
-from distutils.version import LooseVersion
+try:
+    from distutils.version import LooseVersion
+except ImportError:
+    from looseversion import LooseVersion
 from subprocess import (
     check_call,
     check_output,

charmhelpers/core/host.py

@@ -357,7 +357,7 @@ def init_is_systemd(service_name=None):
     return os.path.isdir(SYSTEMD_SYSTEM)
 
 
-def adduser(username, password=None, shell='/bin/bash',
+def adduser(username, password=None, shell=None,
             system_user=False, primary_group=None,
             secondary_groups=None, uid=None, home_dir=None):
     """Add a user to the system.
@@ -389,11 +389,14 @@ def adduser(username, password=None, shell='/bin/bash',
         if home_dir:
             cmd.extend(['--home', str(home_dir)])
         if system_user or password is None:
-            cmd.append('--system')
+            cmd.extend([
+                '--system',
+                '--shell', shell if shell else '/usr/sbin/nologin'
+            ])
         else:
             cmd.extend([
                 '--create-home',
-                '--shell', shell,
+                '--shell', shell if shell else '/bin/bash',
                 '--password', password,
             ])
         if not primary_group:

charmhelpers/fetch/ubuntu.py

@@ -341,7 +341,7 @@ UBUNTU_OPENSTACK_RELEASE = OrderedDict([
 ])
 
 
-APT_NO_LOCK = 100  # The return code for "couldn't acquire lock" in APT.
+APT_ERROR_CODE = 100  # The return code for APT errors.
 CMD_RETRY_DELAY = 10  # Wait 10 seconds between command retries.
 CMD_RETRY_COUNT = 10  # Retry a failing fatal command X times.
 
@@ -464,6 +464,8 @@ def apt_upgrade(options=None, fatal=False, dist=False):
 def apt_update(fatal=False):
     """Update local apt cache."""
     cmd = ['apt-get', 'update']
+    if fatal:
+        cmd.append("--error-on=any")
     _run_apt_command(cmd, fatal)
 
 
@@ -1021,8 +1023,7 @@ def _run_apt_command(cmd, fatal=False, quiet=False):
     """
     if fatal:
         _run_with_retries(
-            cmd, retry_exitcodes=(1, APT_NO_LOCK,),
-            retry_message="Couldn't acquire DPKG lock",
+            cmd, retry_exitcodes=(1, APT_ERROR_CODE,),
             quiet=quiet)
     else:
         kwargs = {}