PR | System Checks Update

src/django_gauth/_checks.py

@@ -0,0 +1,86 @@
+# myapp/checks.py
+import logging
+from enum import Enum
+from typing import Any, Callable
+
+from django.conf import settings  # pylint: disable=E0401
+from django.core.checks import Error  # pylint: disable=E0401
+
+logger = logging.getLogger(__name__)
+
+__app_label__ = "django_gauth"
+
+
+class ErrorCodes(Enum):
+    """Error Codes for app checks"""
+
+    E001 = ("MISSING_REQUIRED_SETTINGS", "Please define the required project settings")
+    E002 = (
+        "MISSING_REQUIRED_MIDDLEWARE",
+        "Please include required middleware in settings",
+    )
+    E003 = (
+        "MISSING_REQUIRED_GOOGLE_CREDENTIALS",
+        "Please include required google oauth2 web client \
+        credentials ( GOOGLE_CLIENT_ID & GOOGLE_CLIENT_SECRET )",
+    )
+    E004 = (
+        "INVALID_GAUTH_SCOPE",
+        "Please set valid oauth2 SCOPE"
+    )
+
+formulate_check_id: Callable = lambda code: f"{__app_label__}.{code}"
+
+
+def check_project_settings(
+    app_configs: object, **kwargs: Any  # pylint: disable=W0613
+) -> list:
+    errors = []
+    if not hasattr(settings, "SECRET_KEY"):
+        errors.append(
+            Error(
+                "SECRET_KEY setting not defined. Required for app:{__app_label__} to work.",
+                hint="Define SECRET_KEY in your project settings.py",
+                id=formulate_check_id(ErrorCodes.E001.name),
+            )
+        )
+    if not hasattr(settings, "GOOGLE_CLIENT_ID"):
+        errors.append(
+            Error(
+                "GOOGLE_CLIENT_ID is not defined in settings."\
+                +   f"Required for app:{__app_label__} to work.",
+                hint="Define GOOGLE_CLIENT_ID in your project settings.py",
+                id=formulate_check_id(ErrorCodes.E003.name),
+            )
+        )
+    if not hasattr(settings, "GOOGLE_CLIENT_SECRET"):
+        errors.append(
+            Error(
+                "GOOGLE_CLIENT_SECRET is not defined in settings."\
+                +   f"Required for app:{__app_label__} to work.",
+                hint="Define GOOGLE_CLIENT_SECRET in your project settings.py",
+                id=formulate_check_id(ErrorCodes.E003.name),
+            )
+        )
+
+    return errors
+
+
+def check_project_middlewares(
+    app_configs: object, **kwargs: Any  # pylint: disable=W0613
+) -> list:
+    errors = []
+
+    session_middleware_path = "django.contrib.sessions.middleware.SessionMiddleware"
+
+    if not session_middleware_path in settings.MIDDLEWARE:
+        errors.append(
+            Error(
+                "Django SessionMiddleware is not included in settings. "\
+                    +   "Required for app:{__app_label__} to work.",
+                hint=f"Define {session_middleware_path} in your "\
+                    +   "project`s MIDDLEWARE variable in settings.py",
+                id=formulate_check_id(ErrorCodes.E002.name),
+            )
+        )
+    return errors

src/django_gauth/admin.py

@@ -1,18 +1,19 @@
 import pprint
-from django.contrib import admin                    # pylint: disable=E0401
+
+from django.contrib import admin  # pylint: disable=E0401
 from django.contrib.sessions.models import Session  # pylint: disable=E0401
 
+
 # pylint: disable=R0903
 class SessionAdmin(admin.ModelAdmin):
     """
     Session information on admin panel
     """
+
     list_display = ["session_key", "_session_data", "expire_date"]
     readonly_fields = ["_session_data"]
-    exclude = [
-        "session_data"
-    ]  # This line ensures that encoded session in not shown .
-       #    Comment this if you want to see the encoded session data as well .
+    exclude = ["session_data"]  # This line ensures that encoded session in not shown .
+    #    Comment this if you want to see the encoded session data as well .
 
     def _session_data(self, obj):
 

src/django_gauth/apps.py

@@ -1,9 +1,124 @@
-from django.apps import AppConfig   # pylint: disable=E0401
+import warnings
+from typing import Any
+
+from django.apps import AppConfig  # pylint: disable=E0401
+
+# pylint: disable=E0602
+from django.conf import settings  # pylint: disable=E0401
+from django.core.checks import Info  # pylint: disable=E0401
+from django.core.checks import register  # pylint: disable=E0401
+from django.core.checks import Tags as DjangoTags  # pylint: disable=E0401
+from django.core.checks import Warning as SysCheckWarning  # pylint: disable=E0401
+
+from django_gauth import defaults
+from django_gauth._checks import (
+    check_project_middlewares,
+    check_project_settings,
+    formulate_check_id,
+    ErrorCodes
+)
+
+warnings.simplefilter("default")
+
+
+# pylint: disable=R0903
+class Tags(DjangoTags):
+    """Extending with Custom Tags
+
+    NOTE : Do this if none of the existing tags work for you:
+    https://docs.djangoproject.com/en/3.1/ref/checks/#builtin-tags
+    """
+
+    django_gauth_compatibility = "django_gauth_compatibility"
+
 
 # pylint: disable=R0903
 class DjangoGauthConfig(AppConfig):
     """
     App Configurator @ django_gauth
     """
+
     default_auto_field = "django.db.models.BigAutoField"
     name = "django_gauth"
+
+    def ready(self) -> None:
+        register(Tags.compatibility)(check_project_middlewares)
+        register(Tags.django_gauth_compatibility)(check_project_settings)
+
+
+@register(Tags.django_gauth_compatibility)
+def set_defaults(
+    app_configs: object, **kwargs: Any  # pylint: disable=W0613
+) -> list:
+    errors = []
+    if not hasattr(settings, "SCOPE"):
+        setattr(settings, "SCOPE", [])
+        errors.append(
+            SysCheckWarning(
+                "SCOPE setting is not defined. Defaulting to `[]`."\
+                +   "It may affect the normal flow of oauth and might not run as expected."\
+                +   "Please rectify ASAP.",
+                hint=(
+                    "See https://masterpiece93.github.io/django-gauth/settings/ "\
+                    +   "for more information."
+                ),
+                id=formulate_check_id(ErrorCodes.E004.name),
+            )
+        )
+
+    if not hasattr(settings, "GOOGLE_AUTH_FINAL_REDIRECT_URL"):
+        setattr(
+            settings,
+            "GOOGLE_AUTH_FINAL_REDIRECT_URL",
+            defaults.GOOGLE_AUTH_FINAL_REDIRECT_URL,
+        )
+        _msg = "GOOGLE_AUTH_FINAL_REDIRECT_URL settings is not defined."\
+        +f"Defaulting to `{defaults.GOOGLE_AUTH_FINAL_REDIRECT_URL}`"
+        warnings.warn(_msg)
+    else:
+        if not settings.GOOGLE_AUTH_FINAL_REDIRECT_URL:
+            _msg = "GOOGLE_AUTH_FINAL_REDIRECT_URL setting is set to"\
+            +   f"`{settings.GOOGLE_AUTH_FINAL_REDIRECT_URL}` which is logically incorrect."
+            info = Info(_msg)
+            errors.append(info)
+    if not hasattr(settings, "CREDENTIALS_SESSION_KEY_NAME"):
+        setattr(
+            settings,
+            "CREDENTIALS_SESSION_KEY_NAME",
+            defaults.CREDENTIALS_SESSION_KEY_NAME,
+        )
+        _msg = "CREDENTIALS_SESSION_KEY_NAME settings is not defined."\
+        +   "Defaulting to `{defaults.CREDENTIALS_SESSION_KEY_NAME}`"
+        warnings.warn(_msg)
+    else:
+        if not settings.CREDENTIALS_SESSION_KEY_NAME:
+            _msg = "CREDENTIALS_SESSION_KEY_NAME setting is set to"\
+            +   "`{settings.CREDENTIALS_SESSION_KEY_NAME}` which is logically incorrect."
+            info = Info(_msg)
+            errors.append(info)
+    if not hasattr(settings, "STATE_KEY_NAME"):
+        setattr(settings, "STATE_KEY_NAME", defaults.STATE_KEY_NAME)
+        _msg = "STATE_KEY_NAME settings is not defined."\
+        +   "Defaulting to `{defaults.STATE_KEY_NAME}`"
+        warnings.warn(_msg)
+    else:
+        if not settings.STATE_KEY_NAME:
+            _msg = f"STATE_KEY_NAME setting is set to `{settings.STATE_KEY_NAME}`"\
+            +   "which is logically incorrect."
+            info = Info(_msg)
+            errors.append(info)
+
+    if not hasattr(settings, "FINAL_REDIRECT_KEY_NAME"):
+        setattr(
+            settings, "FINAL_REDIRECT_KEY_NAME", defaults.FINAL_REDIRECT_KEY_NAME
+        )
+        _msg = "FINAL_REDIRECT_KEY_NAME settings is not defined."\
+        +   "Defaulting to `{defaults.FINAL_REDIRECT_KEY_NAME}`"
+        warnings.warn(_msg)
+    else:
+        if not settings.FINAL_REDIRECT_KEY_NAME:
+            _msg = "FINAL_REDIRECT_KEY_NAME setting is set to"\
+            +   "`{settings.FINAL_REDIRECT_KEY_NAME}` which is logically incorrect."
+            info = Info(_msg)
+            errors.append(info)
+    return errors

src/django_gauth/urls.py

@@ -1,6 +1,6 @@
 # urls
 
-from django.urls import path    # pylint: disable=E0401
+from django.urls import path  # pylint: disable=E0401
 
 from . import views
 

src/django_gauth/utilities.py

@@ -2,8 +2,8 @@
 from typing import Any, Dict, Tuple, Union
 from urllib.parse import urlparse
 
-from django.conf import Settings, settings          # pylint: disable=E0401
-from google.oauth2.credentials import Credentials   # pylint: disable=E0401
+from django.conf import Settings, settings  # pylint: disable=E0401
+from google.oauth2.credentials import Credentials  # pylint: disable=E0401
 
 __all__ = [
     "credentials_to_dict",
@@ -60,8 +60,8 @@ def check_gauth_authentication(session: Settings) -> Tuple[bool, object]:
 
 
 def is_valid_google_url(url: str) -> bool:
-    VALID_SCHEME = "https"              # pylint: disable=C0103
-    VALID_DOMAIN = "docs.google.com"    # pylint: disable=C0103
+    VALID_SCHEME = "https"  # pylint: disable=C0103
+    VALID_DOMAIN = "docs.google.com"  # pylint: disable=C0103
     try:
         result = urlparse(url)
         return (

src/django_gauth/views.py

@@ -3,46 +3,14 @@
 ~@ankit.kumar05
 """
 
-from django.conf import settings                # pylint: disable=E0401
-from django.shortcuts import redirect, render   # pylint: disable=E0401
-from django.urls import reverse                 # pylint: disable=E0401
-from google.auth.transport import requests      # pylint: disable=E0401
-from google.oauth2 import id_token              # pylint: disable=E0401
-from google_auth_oauthlib.flow import Flow      # pylint: disable=E0401
-
-from django_gauth import defaults
-from django_gauth.utilities import check_gauth_authentication, credentials_to_dict
+from django.conf import settings  # pylint: disable=E0401
+from django.shortcuts import redirect, render  # pylint: disable=E0401
+from django.urls import reverse  # pylint: disable=E0401
+from google.auth.transport import requests  # pylint: disable=E0401
+from google.oauth2 import id_token  # pylint: disable=E0401
+from google_auth_oauthlib.flow import Flow  # pylint: disable=E0401
 
-if hasattr(settings, "SCOPE") and settings.SCOPE:
-    SCOPE = settings.SCOPE
-else:
-    SCOPE = []
-
-if (
-    hasattr(settings, "GOOGLE_AUTH_FINAL_REDIRECT_URL")
-    and settings.GOOGLE_AUTH_FINAL_REDIRECT_URL
-):
-    GOOGLE_AUTH_FINAL_REDIRECT_URL = settings.GOOGLE_AUTH_FINAL_REDIRECT_URL
-else:
-    GOOGLE_AUTH_FINAL_REDIRECT_URL = defaults.GOOGLE_AUTH_FINAL_REDIRECT_URL
-
-if (
-    hasattr(settings, "CREDENTIALS_SESSION_KEY_NAME")
-    and settings.CREDENTIALS_SESSION_KEY_NAME
-):
-    CREDENTIALS_SESSION_KEY_NAME = settings.CREDENTIALS_SESSION_KEY_NAME
-else:
-    CREDENTIALS_SESSION_KEY_NAME = defaults.CREDENTIALS_SESSION_KEY_NAME
-
-if hasattr(settings, "STATE_KEY_NAME") and settings.STATE_KEY_NAME:
-    STATE_KEY_NAME = settings.STATE_KEY_NAME
-else:
-    STATE_KEY_NAME = defaults.STATE_KEY_NAME
-
-if hasattr(settings, "FINAL_REDIRECT_KEY_NAME") and settings.FINAL_REDIRECT_KEY_NAME:
-    FINAL_REDIRECT_KEY_NAME = settings.STATE_KEY_NAME
-else:
-    FINAL_REDIRECT_KEY_NAME = defaults.FINAL_REDIRECT_KEY_NAME
+from django_gauth.utilities import check_gauth_authentication, credentials_to_dict
 
 
 def index(request):  # type: ignore
@@ -78,7 +46,7 @@ def login(request):  # type: ignore
         }
         # if you need additional scopes, add them here
         ,
-        scopes=SCOPE,
+        scopes=settings.SCOPE,
     )
 
     # flow.redirect_uri = get_redirect_uri(request) # use this when
@@ -88,13 +56,13 @@ def login(request):  # type: ignore
         access_type="offline", prompt="select_account", include_granted_scopes="true"
     )
 
-    request.session[STATE_KEY_NAME] = state
+    request.session[settings.STATE_KEY_NAME] = state
     if (
         "final_redirect" not in request.session
-        or not request.session[FINAL_REDIRECT_KEY_NAME]
+        or not request.session[settings.FINAL_REDIRECT_KEY_NAME]
     ):
-        request.session[FINAL_REDIRECT_KEY_NAME] = (
-            GOOGLE_AUTH_FINAL_REDIRECT_URL
+        request.session[settings.FINAL_REDIRECT_KEY_NAME] = (
+            settings.GOOGLE_AUTH_FINAL_REDIRECT_URL
             or request.build_absolute_uri(reverse("django_gauth:index"))
         )  # directs where to land after login is successful.
 
@@ -106,7 +74,7 @@ def callback(request):  # type: ignore
     - Google IDP response control transfer
     """
     # pull the state from the session
-    session_state = request.session.get(STATE_KEY_NAME)
+    session_state = request.session.get(settings.STATE_KEY_NAME)
     redirect_uri = request.build_absolute_uri(reverse("django_gauth:callback"))
     authorization_response = request.build_absolute_uri()
     # Flow Creation
@@ -135,15 +103,17 @@ def callback(request):  # type: ignore
     credentials = flow.credentials
     # verify token, while also retrieving information about the user
     id_info = id_token.verify_oauth2_token(
-        id_token=credentials._id_token,     # pylint: disable=W0212
+        id_token=credentials._id_token,  # pylint: disable=W0212
         request=requests.Request(),
         audience=settings.GOOGLE_CLIENT_ID,
         clock_skew_in_seconds=5,
     )
     # session setting
     request.session["id_info"] = id_info
-    request.session[CREDENTIALS_SESSION_KEY_NAME] = credentials_to_dict(credentials)
+    request.session[settings.CREDENTIALS_SESSION_KEY_NAME] = credentials_to_dict(
+        credentials
+    )
     # redirecting to the final redirect (i.e., logged in page)
-    redirect_response = redirect(request.session[FINAL_REDIRECT_KEY_NAME])
+    redirect_response = redirect(request.session[settings.FINAL_REDIRECT_KEY_NAME])
 
     return redirect_response