[AIM] Improve validation output

Validation now catches any exception that leaks from driver validation
methods, reports the error, and exits indicating failure.

Binding of ports during validation is more verbose, indicating which
ports its attempting to bind and how many failed. Failure to bind any
ports now results in a "failed binding ports" rather than "failed
unrepairable" result, along with additonal information on how to
proceed.

Change-Id: I85a180d2a06d7f4442c47424a1c02bc307d1fc0e

gbpservice/neutron/services/grouppolicy/drivers/cisco/apic/aim_validation.py

@@ -122,6 +122,9 @@ class ValidationManager(object):
                     raise RollbackTransaction()
         except RollbackTransaction:
             pass
+        except Exception as exc:
+            self.output("Validation failed with exception: %s" % exc)
+            return api.VALIDATION_FAILED_UNREPAIRABLE
 
         # Bind unbound ports outside transaction.
         if (self.repair and
@@ -225,6 +228,10 @@ class ValidationManager(object):
         self.output("Failed UNREPAIRABLE due to %s" % reason)
         self.result = api.VALIDATION_FAILED_UNREPAIRABLE
 
+    def bind_ports_failed(self, message):
+        self.output(message)
+        self.result = api.VALIDATION_FAILED_BINDING_PORTS
+
     def _validate_aim_resources(self):
         for resource_class in self._expected_aim_resources.keys():
             self._validate_aim_resource_class(resource_class)

gbpservice/neutron/services/grouppolicy/group_policy_driver_api.py

@@ -22,6 +22,7 @@ VALIDATION_PASSED = "passed"
 VALIDATION_REPAIRED = "repaired"
 VALIDATION_FAILED_REPAIRABLE = "failed repairable"
 VALIDATION_FAILED_UNREPAIRABLE = "failed unrepairable"
+VALIDATION_FAILED_BINDING_PORTS = "failed binding ports"
 
 
 @six.add_metaclass(abc.ABCMeta)