[PATCH master 19/28] Create a constant for inst communication tap prefix

[Dimitris Bliablias]

Add a constant value for instance communcation tap prefix "gnt.com.",
named INSTANCE_COMMUNICATION_TAP_PREFIX.

Signed-off-by: Dimitris Bliablias <db...@skroutz.gr>
---
 lib/hypervisor/hv_base.py | 6 +++---
 lib/hypervisor/hv_xen.py  | 3 ++-
 src/Ganeti/Constants.hs   | 3 +++
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/hypervisor/hv_base.py b/lib/hypervisor/hv_base.py
index d4261c6..cb53ccd 100644
--- a/lib/hypervisor/hv_base.py
+++ b/lib/hypervisor/hv_base.py
@@ -196,8 +196,8 @@ def GenerateTapName():
     if len(parts) < 2:
       raise errors.HypervisorError("Failed to parse TUN/TAP interfaces")
 
-    r = re.match(r"gnt\.com\.([0-9]+)", parts[1])
-
+    r = re.match(r"%s([0-9]+)" % constants.INSTANCE_COMMUNICATION_TAP_PREFIX,
+                 parts[1])
     if r is not None:
       idxs.add(int(r.group(1)))
 
@@ -206,7 +206,7 @@ def GenerateTapName():
   else:
     idx = 0
 
-  return "gnt.com.%d" % idx
+  return "".join((constants.INSTANCE_COMMUNICATION_TAP_PREFIX, str(idx)))
 
 
 def ConfigureNIC(cmd, instance, seq, nic, tap):
diff --git a/lib/hypervisor/hv_xen.py b/lib/hypervisor/hv_xen.py
index 2bf021f..7a98a2f 100644
--- a/lib/hypervisor/hv_xen.py
+++ b/lib/hypervisor/hv_xen.py
@@ -899,7 +899,8 @@ class XenHypervisor(hv_base.BaseHypervisor):
                                     result.output, stashed_config))
 
     for nic_seq, nic in enumerate(instance.nics):
-      if nic.name and nic.name.startswith("gnt.com."):
+      if (nic.name and
+          nic.name.startswith(constants.INSTANCE_COMMUNICATION_TAP_PREFIX)):
         _ConfigureNIC(instance, nic_seq, nic, nic.name)
 
   def StopInstance(self, instance, force=False, retry=False, name=None,
diff --git a/src/Ganeti/Constants.hs b/src/Ganeti/Constants.hs
index 7e81446..cf0e689 100644
--- a/src/Ganeti/Constants.hs
+++ b/src/Ganeti/Constants.hs
@@ -5463,6 +5463,9 @@ instanceCommunicationNetworkMode = nicModeRouted
 instanceCommunicationNicPrefix :: String
 instanceCommunicationNicPrefix = "ganeti:communication:"
 
+instanceCommunicationTapPrefix :: String
+instanceCommunicationTapPrefix = "gnt.com."
+
 -- | Parameters that should be protected
 --
 -- Python does not have a type system and can't automatically infer what should
-- 
2.1.4