Merge pull request #43361 from rallytime/bp-43329

Back-port #43329 to 2016.11

salt/cache/consul.py

@@ -4,6 +4,8 @@ Minion data cache plugin for Consul key/value data store.
 
 .. versionadded:: 2016.11.2
 
+:depends: python-consul >= 0.2.0
+
 It is up to the system administrator to set up and configure the Consul
 infrastructure. All is needed for this plugin is a working Consul agent
 with a read-write access to the key-value store.
@@ -81,8 +83,11 @@ def __virtual__():
             'verify': __opts__.get('consul.verify', True),
             }
 
-    global api
-    api = consul.Consul(**consul_kwargs)
+    try:
+        global api
+        api = consul.Consul(**consul_kwargs)
+    except AttributeError:
+        return (False, "Failed to invoke consul.Consul, please make sure you have python-consul >= 0.2.0 installed")
 
     return __virtualname__