chore: fix mypy errors (#197)

fastapi_mail/email_utils/email_check.py

@@ -1,6 +1,6 @@
 import inspect
 from abc import ABC, abstractmethod
-from typing import Any, Dict, List, Set, Union
+from typing import Any, Dict, List, Optional, Set, Union
 
 import dns.exception
 import dns.resolver
@@ -86,14 +86,14 @@ class DefaultChecker(AbstractEmailChecker):
 
     def __init__(
         self,
-        source: str = None,
-        db_provider: str = None,
+        source: Optional[str] = None,
+        db_provider: Optional[str] = None,
         *,
         redis_host: str = "localhost",
         redis_port: int = 6379,
         redis_db: int = 0,
-        redis_password: str = None,
-        username: str = None,
+        redis_password: Optional[str] = None,
+        username: Optional[str] = None,
         **options: dict,
     ):
 
@@ -294,19 +294,25 @@ async def check_mx_record(
     async def blocked_email_count(self) -> int:
         """count all blocked emails in redis"""
         if self.redis_enabled:
-            return await self.redis_client.get("email_counter")
+            result = await self.redis_client.get("email_counter")
+            if result is not None:
+                return result
         return len(self.BLOCKED_ADDRESSES)
 
     async def blocked_domain_count(self) -> int:
         """count all blocked domains in redis"""
         if self.redis_enabled:
-            return await self.redis_client.get("domain_counter")
+            result = await self.redis_client.get("domain_counter")
+            if result is not None:
+                return result
         return len(self.BLOCKED_DOMAINS)
 
     async def temp_email_count(self) -> int:
         """count all temporary emails in redis"""
         if self.redis_enabled:
-            return await self.redis_client.get("temp_counter")
+            result = await self.redis_client.get("temp_counter")
+            if result is not None:
+                return result
         return len(self.TEMP_EMAIL_DOMAINS)
 
     async def close_connections(self) -> bool:

fastapi_mail/fastmail.py

@@ -1,6 +1,6 @@
 from contextlib import contextmanager
 from email.message import EmailMessage, Message
-from typing import Any, Dict, Union
+from typing import Any, Dict, Optional, Union
 
 import blinker
 from jinja2 import Environment, Template
@@ -65,7 +65,7 @@ def check_data(data: Union[Dict[Any, Any], str, None]) -> Dict[Any, Any]:
         return data
 
     async def __prepare_message(
-        self, message: MessageSchema, template: Template = None
+        self, message: MessageSchema, template: Optional[Template] = None
     ) -> Union[EmailMessage, Message]:
         if template and message.template_body is not None:
             message.template_body = await self.__template_message_builder(
@@ -91,7 +91,7 @@ async def __sender(self) -> Union[EmailStr, str]:
         return sender
 
     async def send_message(
-        self, message: MessageSchema, template_name: str = None
+        self, message: MessageSchema, template_name: Optional[str] = None
     ) -> None:
         if not isinstance(message, MessageSchema):
             raise PydanticClassRequired(

fastapi_mail/msg.py

@@ -6,7 +6,7 @@
 from email.mime.multipart import MIMEMultipart
 from email.mime.text import MIMEText
 from email.utils import formatdate, make_msgid
-from typing import Any, Union
+from typing import Any, Optional, Union
 
 from .schemas import MessageType, MultipartSubtypeEnum
 
@@ -107,7 +107,9 @@ def attach_alternative(self, message: MIMEMultipart) -> MIMEMultipart:
         message.attach(tmpmsg)
         return message
 
-    async def _message(self, sender: str = None) -> Union[EmailMessage, Message]:
+    async def _message(
+        self, sender: Optional[str] = None
+    ) -> Union[EmailMessage, Message]:
         """
         Creates the email message
         """