S3SignView: cleanup method signatures and use tz-aware datetime

A number of these methods are actually static methods, and don't rely on
the object instance. I'm cleaning up some of the code here, and also
updating the datetime.now() to call timezone.now(), as recommended by
Django and which we use everywhere else.

CHANGES

@@ -2,6 +2,8 @@
 ==================
 * Refactored upload logic out of view code
 * Added .avif image format.
+* Clean up SignS3View method signatures
+* Use timezone-aware datetime object in SignS3View
 
 0.4.1 (2025-01-10)
 ==================

s3sign/views.py

@@ -6,11 +6,10 @@
 
 import boto3
 
-from datetime import datetime
-
 from django.conf import settings
 from django.http import HttpResponse
 from django.views.generic import View
+from django.utils import timezone
 
 from s3sign.utils import s3_config, upload_file
 
@@ -59,34 +58,37 @@ def dispatch(self, request, *args, **kwargs):
         )
         return super().dispatch(request, *args, **kwargs)
 
-    def get_name_field(self):
+    def get_name_field(self) -> str:
         return self.name_field
 
-    def get_type_field(self):
+    def get_type_field(self) -> str:
         return self.type_field
 
     def get_expiration_time(self):
         return self.expiration_time
 
-    def get_mime_type_extensions(self):
+    def get_mime_type_extensions(self) -> list:
         return self.mime_type_extensions
 
-    def get_default_extension(self):
+    def get_default_extension(self) -> str:
         return self.default_extension
 
-    def get_root(self):
+    def get_root(self) -> str:
         return self.root
 
-    def get_path_string(self):
+    def get_path_string(self) -> str:
         return self.path_string
 
-    def get_aws_access_key(self):
+    @staticmethod
+    def get_aws_access_key() -> str:
         return settings.AWS_ACCESS_KEY
 
-    def get_aws_secret_key(self):
+    @staticmethod
+    def get_aws_secret_key() -> str:
         return settings.AWS_SECRET_KEY
 
-    def get_bucket(self):
+    @staticmethod
+    def get_bucket() -> str:
         return settings.AWS_UPLOAD_BUCKET
 
     def get_mimetype(self, request):
@@ -98,21 +100,24 @@ def extension_from_mimetype(self, mime_type):
                 return ext
         return self.get_default_extension()
 
-    def now(self):
-        return datetime.now()
+    @staticmethod
+    def now():
+        return timezone.now()
 
-    def now_time(self):
+    @staticmethod
+    def now_time():
         return time.time()
 
-    def basename(self, request):
+    @staticmethod
+    def basename():
         return str(uuid.uuid4())
 
     def extension(self, request):
         return self.extension_from_mimetype(self.get_mimetype(request))
 
     def get_object_name(self, request):
         now = self.now()
-        basename = self.basename(request)
+        basename = self.basename()
         extension = self.extension(request)
         return self.get_path_string().format(
             now=now, basename=basename, extension=extension,