Upgraded to pylint 2.x (#384)

* Removing Python 2 support

* Upgraded to Pylint 2.x and fixed all linter errors for Python 3

* Downgrading to pylint 2.3 since 2.4 won't install on Python 3.4

Author: hiranya911

.travis.yml

@@ -9,7 +9,7 @@ python:
 jobs:
   include:
     - name: "Lint"
-      python: "2.7"
+      python: "3.7"
       script: ./lint.sh all
 
 before_install:

firebase_admin/__init__.py

@@ -77,12 +77,12 @@ def initialize_app(credential=None, options=None, name=_DEFAULT_APP_NAME):
             'initialize_app() once. But if you do want to initialize multiple '
             'apps, pass a second argument to initialize_app() to give each app '
             'a unique name.'))
-    else:
-        raise ValueError((
-            'Firebase app named "{0}" already exists. This means you called '
-            'initialize_app() more than once with the same app name as the '
-            'second argument. Make sure you provide a unique name every time '
-            'you call initialize_app().').format(name))
+
+    raise ValueError((
+        'Firebase app named "{0}" already exists. This means you called '
+        'initialize_app() more than once with the same app name as the '
+        'second argument. Make sure you provide a unique name every time '
+        'you call initialize_app().').format(name))
 
 
 def delete_app(app):
@@ -106,11 +106,11 @@ def delete_app(app):
         raise ValueError(
             'The default Firebase app is not initialized. Make sure to initialize '
             'the default app by calling initialize_app().')
-    else:
-        raise ValueError(
-            ('Firebase app named "{0}" is not initialized. Make sure to initialize '
-             'the app by calling initialize_app() with your app name as the '
-             'second argument.').format(app.name))
+
+    raise ValueError(
+        ('Firebase app named "{0}" is not initialized. Make sure to initialize '
+         'the app by calling initialize_app() with your app name as the '
+         'second argument.').format(app.name))
 
 
 def get_app(name=_DEFAULT_APP_NAME):
@@ -137,14 +137,14 @@ def get_app(name=_DEFAULT_APP_NAME):
         raise ValueError(
             'The default Firebase app does not exist. Make sure to initialize '
             'the SDK by calling initialize_app().')
-    else:
-        raise ValueError(
-            ('Firebase app named "{0}" does not exist. Make sure to initialize '
-             'the SDK by calling initialize_app() with your app name as the '
-             'second argument.').format(name))
+
+    raise ValueError(
+        ('Firebase app named "{0}" does not exist. Make sure to initialize '
+         'the SDK by calling initialize_app() with your app name as the '
+         'second argument.').format(name))
 
 
-class _AppOptions(object):
+class _AppOptions:
     """A collection of configuration options for an App."""
 
     def __init__(self, options):
@@ -185,7 +185,7 @@ def _load_from_environment(self):
         return {k: v for k, v in json_data.items() if k in _CONFIG_VALID_KEYS}
 
 
-class App(object):
+class App:
     """The entry point for Firebase Python SDK.
 
     Represents a Firebase app, while holding the configuration and state

firebase_admin/_auth_utils.py

@@ -103,6 +103,7 @@ def validate_provider_id(provider_id, required=True):
     return provider_id
 
 def validate_photo_url(photo_url, required=False):
+    """Parses and validates the given URL string."""
     if photo_url is None and not required:
         return None
     if not isinstance(photo_url, six.string_types) or not photo_url:
@@ -118,6 +119,7 @@ def validate_photo_url(photo_url, required=False):
         raise ValueError('Malformed photo URL: "{0}".'.format(photo_url))
 
 def validate_timestamp(timestamp, label, required=False):
+    """Validates the given timestamp value. Timestamps must be positive integers."""
     if timestamp is None and not required:
         return None
     if isinstance(timestamp, bool):
@@ -181,7 +183,7 @@ def validate_custom_claims(custom_claims, required=False):
     if len(invalid_claims) > 1:
         joined = ', '.join(sorted(invalid_claims))
         raise ValueError('Claims "{0}" are reserved, and must not be set.'.format(joined))
-    elif len(invalid_claims) == 1:
+    if len(invalid_claims) == 1:
         raise ValueError(
             'Claim "{0}" is reserved, and must not be set.'.format(invalid_claims.pop()))
     return claims_str

firebase_admin/_http_client.py

@@ -32,7 +32,7 @@
     raise_on_status=False, backoff_factor=0.5)
 
 
-class HttpClient(object):
+class HttpClient:
     """Base HTTP client used to make HTTP calls.
 
     HttpClient maintains an HTTP session, and handles request authentication and retries if

firebase_admin/_messaging_encoder.py

@@ -25,7 +25,7 @@
 import firebase_admin._messaging_utils as _messaging_utils
 
 
-class Message(object):
+class Message:
     """A message that can be sent via Firebase Cloud Messaging.
 
     Contains payload information as well as recipient information. In particular, the message must
@@ -61,7 +61,7 @@ def __str__(self):
         return json.dumps(self, cls=MessageEncoder, sort_keys=True)
 
 
-class MulticastMessage(object):
+class MulticastMessage:
     """A message that can be sent to multiple tokens via Firebase Cloud Messaging.
 
     Args:
@@ -88,7 +88,7 @@ def __init__(self, tokens, data=None, notification=None, android=None, webpush=N
         self.fcm_options = fcm_options
 
 
-class _Validators(object):
+class _Validators:
     """A collection of data validation utilities.
 
     Methods provided in this class raise ``ValueErrors`` if any validations fail.
@@ -102,8 +102,7 @@ def check_string(cls, label, value, non_empty=False):
         if not isinstance(value, six.string_types):
             if non_empty:
                 raise ValueError('{0} must be a non-empty string.'.format(label))
-            else:
-                raise ValueError('{0} must be a string.'.format(label))
+            raise ValueError('{0} must be a string.'.format(label))
         if non_empty and not value:
             raise ValueError('{0} must be a non-empty string.'.format(label))
         return value
@@ -647,6 +646,7 @@ def encode_notification(cls, notification):
 
     @classmethod
     def sanitize_topic_name(cls, topic):
+        """Removes the /topics/ prefix from the topic name, if present."""
         if not topic:
             return None
         prefix = '/topics/'
@@ -657,20 +657,20 @@ def sanitize_topic_name(cls, topic):
             raise ValueError('Malformed topic name.')
         return topic
 
-    def default(self, obj): # pylint: disable=method-hidden
-        if not isinstance(obj, Message):
-            return json.JSONEncoder.default(self, obj)
+    def default(self, o): # pylint: disable=method-hidden
+        if not isinstance(o, Message):
+            return json.JSONEncoder.default(self, o)
         result = {
-            'android': MessageEncoder.encode_android(obj.android),
-            'apns': MessageEncoder.encode_apns(obj.apns),
+            'android': MessageEncoder.encode_android(o.android),
+            'apns': MessageEncoder.encode_apns(o.apns),
             'condition': _Validators.check_string(
-                'Message.condition', obj.condition, non_empty=True),
-            'data': _Validators.check_string_dict('Message.data', obj.data),
-            'notification': MessageEncoder.encode_notification(obj.notification),
-            'token': _Validators.check_string('Message.token', obj.token, non_empty=True),
-            'topic': _Validators.check_string('Message.topic', obj.topic, non_empty=True),
-            'webpush': MessageEncoder.encode_webpush(obj.webpush),
-            'fcm_options': MessageEncoder.encode_fcm_options(obj.fcm_options),
+                'Message.condition', o.condition, non_empty=True),
+            'data': _Validators.check_string_dict('Message.data', o.data),
+            'notification': MessageEncoder.encode_notification(o.notification),
+            'token': _Validators.check_string('Message.token', o.token, non_empty=True),
+            'topic': _Validators.check_string('Message.topic', o.topic, non_empty=True),
+            'webpush': MessageEncoder.encode_webpush(o.webpush),
+            'fcm_options': MessageEncoder.encode_fcm_options(o.fcm_options),
         }
         result['topic'] = MessageEncoder.sanitize_topic_name(result.get('topic'))
         result = MessageEncoder.remove_null_values(result)

firebase_admin/_messaging_utils.py

@@ -17,7 +17,7 @@
 from firebase_admin import exceptions
 
 
-class Notification(object):
+class Notification:
     """A notification that can be included in a message.
 
     Args:
@@ -32,7 +32,7 @@ def __init__(self, title=None, body=None, image=None):
         self.image = image
 
 
-class AndroidConfig(object):
+class AndroidConfig:
     """Android-specific options that can be included in a message.
 
     Args:
@@ -62,7 +62,7 @@ def __init__(self, collapse_key=None, priority=None, ttl=None, restricted_packag
         self.fcm_options = fcm_options
 
 
-class AndroidNotification(object):
+class AndroidNotification:
     """Android-specific notification parameters.
 
     Args:
@@ -178,7 +178,7 @@ def __init__(self, title=None, body=None, icon=None, color=None, sound=None, tag
         self.notification_count = notification_count
 
 
-class LightSettings(object):
+class LightSettings:
     """Represents settings to control notification LED that can be included in a
     ``messaging.AndroidNotification``.
 
@@ -196,7 +196,7 @@ def __init__(self, color, light_on_duration_millis,
         self.light_off_duration_millis = light_off_duration_millis
 
 
-class AndroidFCMOptions(object):
+class AndroidFCMOptions:
     """Options for features provided by the FCM SDK for Android.
 
     Args:
@@ -208,7 +208,7 @@ def __init__(self, analytics_label=None):
         self.analytics_label = analytics_label
 
 
-class WebpushConfig(object):
+class WebpushConfig:
     """Webpush-specific options that can be included in a message.
 
     Args:
@@ -230,7 +230,7 @@ def __init__(self, headers=None, data=None, notification=None, fcm_options=None)
         self.fcm_options = fcm_options
 
 
-class WebpushNotificationAction(object):
+class WebpushNotificationAction:
     """An action available to the users when the notification is presented.
 
     Args:
@@ -245,7 +245,7 @@ def __init__(self, action, title, icon=None):
         self.icon = icon
 
 
-class WebpushNotification(object):
+class WebpushNotification:
     """Webpush-specific notification parameters.
 
     Refer to the `Notification Reference`_ for more information.
@@ -302,7 +302,7 @@ def __init__(self, title=None, body=None, icon=None, actions=None, badge=None, d
         self.custom_data = custom_data
 
 
-class WebpushFCMOptions(object):
+class WebpushFCMOptions:
     """Options for features provided by the FCM SDK for Web.
 
     Args:
@@ -314,7 +314,7 @@ def __init__(self, link=None):
         self.link = link
 
 
-class APNSConfig(object):
+class APNSConfig:
     """APNS-specific options that can be included in a message.
 
     Refer to `APNS Documentation`_ for more information.
@@ -335,7 +335,7 @@ def __init__(self, headers=None, payload=None, fcm_options=None):
         self.fcm_options = fcm_options
 
 
-class APNSPayload(object):
+class APNSPayload:
     """Payload of an APNS message.
 
     Args:
@@ -349,7 +349,7 @@ def __init__(self, aps, **kwargs):
         self.custom_data = kwargs
 
 
-class Aps(object):
+class Aps:
     """Aps dictionary to be included in an APNS payload.
 
     Args:
@@ -379,7 +379,7 @@ def __init__(self, alert=None, badge=None, sound=None, content_available=None, c
         self.custom_data = custom_data
 
 
-class CriticalSound(object):
+class CriticalSound:
     """Critical alert sound configuration that can be included in ``messaging.Aps``.
 
     Args:
@@ -398,7 +398,7 @@ def __init__(self, name, critical=None, volume=None):
         self.volume = volume
 
 
-class ApsAlert(object):
+class ApsAlert:
     """An alert that can be included in ``messaging.Aps``.
 
     Args:
@@ -437,7 +437,7 @@ def __init__(self, title=None, subtitle=None, body=None, loc_key=None, loc_args=
         self.custom_data = custom_data
 
 
-class APNSFCMOptions(object):
+class APNSFCMOptions:
     """Options for features provided by the FCM SDK for iOS.
 
     Args:
@@ -452,7 +452,7 @@ def __init__(self, analytics_label=None, image=None):
         self.image = image
 
 
-class FCMOptions(object):
+class FCMOptions:
     """Options for features provided by SDK.
 
     Args:

firebase_admin/_sseclient.py

@@ -40,7 +40,7 @@ def rebuild_auth(self, prepared_request, response):
         pass
 
 
-class _EventBuffer(object):
+class _EventBuffer:
     """A helper class for buffering and parsing raw SSE data."""
 
     def __init__(self):
@@ -68,7 +68,7 @@ def buffer_string(self):
         return ''.join(self._buffer)
 
 
-class SSEClient(object):
+class SSEClient:
     """SSE client implementation."""
 
     def __init__(self, url, session, retry=3000, **kwargs):
@@ -140,7 +140,7 @@ def __next__(self):
         if event.data == 'credential is no longer valid':
             self._connect()
             return None
-        elif event.data == 'null':
+        if event.data == 'null':
             return None
 
         # If the server requests a specific retry delay, we need to honor it.
@@ -157,7 +157,7 @@ def next(self):
         return self.__next__()
 
 
-class Event(object):
+class Event:
     """Event represents the events fired by SSE."""
 
     sse_line_pattern = re.compile('(?P<name>[^:]*):?( ?(?P<value>.*))?')
@@ -192,7 +192,7 @@ def parse(cls, raw):
             if name == '':
                 # line began with a ":", so is a comment.  Ignore
                 continue
-            elif name == 'data':
+            if name == 'data':
                 # If we already have some data, then join to it with a newline.
                 # Else this is it.
                 if event.data: