Solve some issues pointed out by pylint in senza/templates/*

senza/templates/__init__.py

@@ -1,13 +1,22 @@
+"""
+Modules and functions for senza component templates
+"""
+
 from types import ModuleType, FunctionType
 import pkg_resources
 
 
-def get_template_description(name, module: ModuleType):
+def get_template_description(name, module: ModuleType) -> str:
+    """
+    Gets the human-readable template description based on the name of the
+    component and the component's module docstring
+    """
     return '{}: {}'.format(name, (module.__doc__ or "").strip())
 
 
 def has_functions(module, names):
-    return all(isinstance(getattr(module, function_name, None), FunctionType) for function_name in names)
+    return all(isinstance(getattr(module, function_name, None), FunctionType)
+               for function_name in names)
 
 
 def get_templates() -> dict:
@@ -16,15 +25,15 @@ def get_templates() -> dict:
     """
     entry_points = pkg_resources.iter_entry_points('senza.templates')
     template_modules = {}
-    for e in entry_points:  # type: pkg_resources.EntryPoint
+    for entry_point in entry_points:  # type: pkg_resources.EntryPoint
         try:
-            module = e.resolve()
+            module = entry_point.resolve()
         except ImportError:
             # ignore bad entry points
             continue
         else:
             # make sure the entry point resolves to a module with the essential interface functions
             if (isinstance(module, ModuleType) and
-               has_functions(module, ('gather_user_variables', 'generate_definition'))):
-                template_modules[e.name] = module
+                    has_functions(module, ('gather_user_variables', 'generate_definition'))):
+                template_modules[entry_point.name] = module
     return template_modules

senza/templates/postgresapp.py

@@ -398,7 +398,7 @@ def gather_user_variables(variables, region, account_info):
     prompt(variables, 'instance_type', 'EC2 instance type', default='t2.medium')
 
     variables['hosted_zone'] = account_info.Domain or defaults['hosted_zone']
-    if (variables['hosted_zone'][-1:] != '.'):
+    if variables['hosted_zone'][-1:] != '.':
         variables['hosted_zone'] += '.'
     prompt(variables, 'discovery_domain', 'ETCD Discovery Domain',
            default='postgres.' + variables['hosted_zone'][:-1])
@@ -503,11 +503,14 @@ def get_latest_image(registry_domain='registry.opensource.zalan.do', team='acid'
     Gets the full name of latest image for an artifact
     """
     try:
-        r = requests.get('https://{0}/teams/{1}/artifacts/{2}/tags'.format(registry_domain, team, artifact))
-        if r.ok:
+        url = 'https://{0}/teams/{1}/artifacts/{2}/tags'.format(registry_domain,
+                                                                team,
+                                                                artifact)
+        response = requests.get(url)
+        if response.ok:
             # sort the tags by creation date
             latest = None
-            for entry in sorted(r.json(), key=lambda t: t['created'], reverse=True):
+            for entry in sorted(response.json(), key=lambda t: t['created'], reverse=True):
                 tag = entry['name']
                 # try to avoid snapshots if possible
                 if 'SNAPSHOT' not in tag:

senza/templates/redisnode.py

@@ -1,6 +1,6 @@
-'''
+"""
 Elasticache node running redis, without replication / HA (for caching)
-'''
+"""
 
 from clickclick import warning
 from senza.utils import pystache_render
@@ -28,7 +28,10 @@
 '''
 
 
-def gather_user_variables(variables, region, account_info):
+def gather_user_variables(variables, region, account_info):  # pylint: disable=locally-disabled, unused-argument
+    """
+    Gather all the variables needed to create the redis node
+    """
     # maximal 32 characters because of the loadbalancer-name
     prompt(variables, 'application_id', 'Application ID', default='hello-world',
            value_proc=check_value(18, '^[a-zA-Z][-a-zA-Z0-9]*$'))
@@ -38,12 +41,15 @@ def gather_user_variables(variables, region, account_info):
 
     rules_missing = check_security_group(sg_name, [('tcp', 6379)], region, allow_from_self=True)
     if ('tcp', 6379) in rules_missing:
-        warning('Security group {} does not allow tcp/6379 access, you will not be able to access your redis'.format(
-            sg_name))
+        warning('Security group {} does not allow tcp/6379 access, '
+                'you will not be able to access your redis'.format(sg_name))
 
     return variables
 
 
 def generate_definition(variables):
+    """
+    Generates the redis node definition yaml from template
+    """
     definition_yaml = pystache_render(TEMPLATE, variables)
     return definition_yaml