Fix node generation if param is None
diff --git a/sphinx/files/salt/source/nodes/node.rst b/sphinx/files/salt/source/nodes/node.rst
index e08358b..8b622b1 100644
--- a/sphinx/files/salt/source/nodes/node.rst
+++ b/sphinx/files/salt/source/nodes/node.rst
@@ -24,12 +24,14 @@
- **Value**
{%- if service.role is mapping %}
{%- for role_name, role in service.role.iteritems() %}
+{%- if role.get('param', {}) %}
{%- for param_name, param in role.get('param', {}).iteritems() %}
* - {{ service_name }}-{{ role_name }}
- {{ param.get('name', param_name) }}
-
{{ render_list(param.value)|indent(8, True) }}
{%- endfor %}
+{%- endif %}
{%- endfor %}
{%- endif %}