dcnm_fabric: hardening (#349)

Two bits of vulnerable code found when porting to ndfc-python.

1. plugins/modules/dcnm_fabric.py

Accessing dictionary key directly can lead to a KeyError exception.

2. plugins/module_utils/fabric/replaced.py

If user omits the DEPLOY parameter from their playbook (ndfc-python) the DEPLOY key would be None, and not get popped from the payload.  This would cause NDFC to complain about an invalid key in the payload.  We need to unconditionally pop DEPLOY here, if it's present.  Hence, we've removed the value check (if DEPLOY is not None).

plugins/module_utils/fabric/replaced.py

@@ -468,7 +468,7 @@ def _send_payloads(self):
 
         for payload in self._payloads_to_commit:
             commit_payload = copy.deepcopy(payload)
-            if commit_payload.get("DEPLOY", None) is not None:
+            if "DEPLOY" in commit_payload:
                 commit_payload.pop("DEPLOY")
             try:
                 self._send_payload(commit_payload)

plugins/modules/dcnm_fabric.py

@@ -3032,7 +3032,7 @@ def get_need(self):
             fabric_name = want.get("FABRIC_NAME", None)
             fabric_type = want.get("FABRIC_TYPE", None)
 
-            if self.features[fabric_type] is False:
+            if self.features.get("fabric_type") is False:
                 msg = f"{self.class_name}.{method_name}: "
                 msg += f"Features required for fabric {fabric_name} "
                 msg += f"of type {fabric_type} are not running on the "
@@ -3361,7 +3361,7 @@ def get_need(self):
                 self.need_create.append(want)
                 continue
 
-            if self.features[fabric_type] is False:
+            if self.features.get("fabric_type") is False:
                 msg = f"{self.class_name}.{method_name}: "
                 msg += f"Features required for fabric {fabric_name} "
                 msg += f"of type {fabric_type} are not running on the "