Truncate edge appliance name when too long

This patch addresses an issue when a user sets a very long name to an
exclusive or distributed routers.
Currently we set the edge appliance name to <router-name>-<router-id> and
this may exceed the maximum length which is allowed by NSXv.

Change-Id: I9db4b5420227fe9cb4356743de86792e0440b575

vmware_nsx/common/nsxv_constants.py

@@ -36,6 +36,9 @@ INTERNAL_TENANT_ID = 'a1b2c3d4-e5f6-eeff-ffee-6f5e4d3c2b1a'
 # L2 gateway edge name prefix
 L2_GATEWAY_EDGE = 'L2 bridging'
 
+# An artificial limit for router name length - subtract 1 for the - separator
+ROUTER_NAME_LENGTH = (78 - 1)
+
 # LoadBalancer Certificate constants
 #NOTE(abhiraut): Number of days specify the total number of days for which the
 #                the certificate will be active. This certificate will expire

vmware_nsx/plugins/nsx_v/vshield/edge_utils.py

@@ -645,7 +645,10 @@ class EdgeManager(object):
         self, context, lrouter, lswitch=None, dist=False,
         appliance_size=vcns_const.SERVICE_SIZE_MAPPING['router']):
         """Create an edge for logical router support."""
-        router_name = lrouter['name'] + '-' + lrouter['id']
+        router_name = (
+            lrouter['name'][:nsxv_constants.ROUTER_NAME_LENGTH -
+                            len(lrouter['id'])] +
+            '-' + lrouter['id'])
         self._allocate_edge_appliance(
             context, lrouter['id'], router_name,
             appliance_size=appliance_size,