Remove None from util.py helpers

marathon_lb.py

@@ -1412,7 +1412,7 @@ def get_apps(marathon):
                         continue
 
             task_ip, task_ports = get_task_ip_and_ports(app, task)
-            if not task_ip:
+            if task_ip is None:
                 logger.warning("Task has no resolvable IP address - skip")
                 continue
 

tests/test_utils.py

@@ -2,6 +2,8 @@
 
 from mock import Mock, patch
 
+from common import cleanup_json
+
 import utils
 from utils import ServicePortAssigner
 
@@ -412,9 +414,36 @@ def test_ip_per_task_portMappings_null(self):
                 },
             ],
         }
-        self.assertEquals(self.assigner.get_service_ports(app),
+        # Calling cleanup_json because all entrypoints to get_service_ports
+        # also call cleanup_json, so None isn't expected at runtime
+        self.assertEquals(self.assigner.get_service_ports(cleanup_json(app)),
                           [10000, 10001])
 
+    def test_ip_per_task_portMappings_null_marathon15(self):
+        app = {
+            'container': {
+                'type': 'DOCKER',
+                'docker': {
+                    'image': 'nginx'
+                },
+                'portMappings': None
+            },
+            'networks': [
+                {
+                    'mode': 'container',
+                    'name': 'dcos'
+                }
+            ],
+            'tasks': [{
+                "id": "testtaskid",
+                "ipAddresses": [{"ipAddress": "1.2.3.4"}]
+            }],
+        }
+        # Calling cleanup_json because all entrypoints to get_service_ports
+        # also call cleanup_json, so None isn't expected at runtime
+        self.assertEquals(self.assigner.get_service_ports(cleanup_json(app)),
+                          [])
+
 
 def _get_app(idx=1, num_ports=3, num_tasks=1, ip_per_task=True,
              inc_service_ports=False):

utils.py

@@ -118,7 +118,7 @@ def get_service_ports(self, app):
         if mode == "container" or mode == "container/bridge":
             # Here we must use portMappings
             portMappings = get_app_port_mappings(app)
-            if portMappings:
+            if len(portMappings) > 0:
                 ports = filter(lambda p: p is not None,
                                map(lambda p: p.get('servicePort', None),
                                    portMappings))
@@ -138,7 +138,7 @@ def get_service_ports(self, app):
                 and len(app['tasks']) > 0:
             task = app['tasks'][0]
             task_ports = get_app_task_ports(app, task, mode)
-            if task_ports is not None:
+            if len(task_ports) > 0:
                 ports = [self._get_service_port(app, task_port)
                          for task_port in task_ports]
         logger.debug("Service ports: %r", ports)
@@ -257,8 +257,11 @@ def _split_lines_from_chunks(chunks):
 
 
 def resolve_ip(host):
-    cached_ip = ip_cache.get().get(host, None)
-    if cached_ip:
+    """
+    :return: string, an empty string indicates that no ip was found.
+    """
+    cached_ip = ip_cache.get().get(host, "")
+    if cached_ip != "":
         return cached_ip
     else:
         try:
@@ -267,7 +270,7 @@ def resolve_ip(host):
             ip_cache.get().set(host, ip)
             return ip
         except socket.gaierror:
-            return None
+            return ""
 
 
 class LRUCacheSingleton(object):
@@ -309,95 +312,105 @@ def get_app_networking_mode(app):
 
 
 def get_task_ip(task, mode):
+    """
+    :return: string, an empty string indicates that no ip was found.
+    """
     if mode == 'container':
         task_ip_addresses = task.get('ipAddresses', [])
-        if not task_ip_addresses:
+        if len(task_ip_addresses) == 0:
             logger.warning("Task %s does not yet have an ip address allocated",
                            task['id'])
-            return None
-        task_ip = task_ip_addresses[0].get('ipAddress')
-        if not task_ip:
+            return ""
+        task_ip = task_ip_addresses[0].get('ipAddress', "")
+        if task_ip == "":
             logger.warning("Task %s does not yet have an ip address allocated",
                            task['id'])
-            return None
+            return ""
         return task_ip
     else:
-        host = task.get('host')
-        if not host:
+        host = task.get('host', "")
+        if host == "":
             logger.warning("Could not find task host, ignoring")
+            return ""
         task_ip = resolve_ip(host)
-        if not task_ip:
+        if task_ip == "":
             logger.warning("Could not resolve ip for host %s, ignoring",
                            host)
+            return ""
         return task_ip
 
 
 def get_app_port_mappings(app):
+    """
+    :return: list
+    """
     portMappings = app.get('container', {})\
                       .get('docker', {})\
-                      .get('portMappings')
-    if portMappings is not None:
+                      .get('portMappings', [])
+    if len(portMappings) > 0:
         return portMappings
 
-    portMappings = app.get('container', {})\
-                      .get('portMappings', [])
-    return portMappings
+    return app.get('container', {})\
+              .get('portMappings', [])
 
 
 def get_task_ports(task):
-    return task.get('ports')
+    """
+    :return: list
+    """
+    return task.get('ports', [])
 
 
 def get_port_definition_ports(app):
+    """
+    :return: list
+    """
     port_definitions = app.get('portDefinitions', [])
-    task_ports = [p['port']
-                  for p in port_definitions
-                  if 'port' in p]
-    if len(task_ports) == 0:
-        return None
-    return task_ports
+    return [p['port'] for p in port_definitions if 'port' in p]
 
 
 def get_ip_address_discovery_ports(app):
+    """
+    :return: list
+    """
     ip_address = app.get('ipAddress', {})
-    if ip_address:
-        discovery = app.get('ipAddress', {}).get('discovery', {})
-        task_ports = [int(p['number'])
-                      for p in discovery.get('ports', [])
-                      if 'number' in p]
-        if len(task_ports) > 0:
-            return task_ports
-    return None
+    if len(ip_address) == 0:
+        return []
+    discovery = app.get('ipAddress', {}).get('discovery', {})
+    return [int(p['number'])
+            for p in discovery.get('ports', [])
+            if 'number' in p]
 
 
 def get_port_mapping_ports(app):
+    """
+    :return: list
+    """
     port_mappings = get_app_port_mappings(app)
-    task_ports = [p['containerPort']
-                  for p in port_mappings
-                  if 'containerPort' in p]
-    if len(task_ports) == 0:
-        return None
-    return task_ports
+    return [p['containerPort'] for p in port_mappings if 'containerPort' in p]
 
 
 def get_app_task_ports(app, task, mode):
+    """
+    :return: list
+    """
     if mode == 'host':
         task_ports = get_task_ports(task)
-        if task_ports:
+        if len(task_ports) > 0:
             return task_ports
         return get_port_definition_ports(app)
     elif mode == 'container/bridge':
         task_ports = get_task_ports(task)
-        if task_ports:
+        if len(task_ports) > 0:
             return task_ports
         # Will only work for Marathon < 1.5
         task_ports = get_port_definition_ports(app)
-        if task_ports:
+        if len(task_ports) > 0:
             return task_ports
         return get_port_mapping_ports(app)
     else:
         task_ports = get_ip_address_discovery_ports(app)
-        if task_ports:
+        if len(task_ports) > 0:
             return task_ports
         return get_port_mapping_ports(app)
 
@@ -417,6 +430,7 @@ def get_task_ip_and_ports(app, task):
     mode = get_app_networking_mode(app)
     task_ip = get_task_ip(task, mode)
     task_ports = get_app_task_ports(app, task, mode)
+    # The overloading of empty string, and empty list as False is intentional.
     if not (task_ip and task_ports):
         return None, None
     logger.debug("Returning: %r, %r", task_ip, task_ports)

zdd.py

@@ -222,7 +222,7 @@ def select_drained_listeners(listeners):
 
 def get_svnames_from_task(app, task):
     prefix = task['host'].replace('.', '_')
-    task_ip, task_port = get_task_ip_and_ports(app, task)
+    task_ip, _ = get_task_ip_and_ports(app, task)
     if task['host'] == task_ip:
         for port in task['ports']:
             yield('{}_{}'.format(prefix, port))
@@ -645,7 +645,7 @@ def prepare_deploy(args, previous_deploys, app):
 
 def load_app_json(args):
     with open(args.json) as content_file:
-        return json.load(content_file)
+        return cleanup_json(json.load(content_file))
 
 
 def safe_resume_deploy(args, previous_deploys):