consul: Always fail if no service_name was provided. (#25877)

Fixes a subtile bug introduced in PR #21737

lib/ansible/modules/clustering/consul.py

@@ -389,8 +389,8 @@ def parse_service(module):
             module.params.get('service_port'),
             module.params.get('tags'),
         )
-    elif module.params.get('service_port') and not module.params.get('service_name'):
-        module.fail_json(msg="service_port supplied but no service_name, a name is required to configure a service.")
+    elif not module.params.get('service_name'):
+        module.fail_json(msg="service_name is required to configure a service.")
 
 
 class ConsulService():

test/integration/roles/test_consul_service/tasks/main.yml

@@ -47,6 +47,17 @@
         - basic2_result.service_id == 'service2'
         - basic2_result.service_name == 'Basic Service'
 
+- name: register service without name
+  consul:
+    service_id: this_will_fail
+  register: noname_result
+  ignore_errors: True
+
+- name: verify registering service without name fails
+  assert:
+    that:
+        - noname_result | failed
+
 - name: register very basic service without service_port
   consul:
     service_name: Basic Service Without Port