[rewrite] Added a security module from a fastapi example

backend/app/core/config.py

@@ -155,22 +155,27 @@ class EnvConfigField():
                           value=value)
 
 
-class EnvConfig:
-    """Singleton configuration loader for environment variables."""
+class EnvConfig():
 
     _instance = None
+    _initialized = False
 
     def __new__(cls):
-        """Ensures only one instance of EnvConfig is created."""
+        print("Called __new__")
         if cls._instance is None:
             cls._instance = super().__new__(cls)
         return cls._instance
 
     def __init__(self):
+        if EnvConfig._initialized:
+            return
+
         self.logger = logging.getLogger(__name__)
 
         self.fields = {}
 
+        EnvConfig._initialized = True
+
     def add_field(self, name: str, field: EnvConfigField):
         if name in self.fields:
             return

backend/app/core/security.py

@@ -0,0 +1,30 @@
+from datetime import datetime, timedelta, timezone
+from typing import Any
+
+import jwt
+
+from passlib.context import CryptContext
+
+from app.core.config import EnvConfig
+
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+
+
+ALGORITHM = "HS256"
+
+
+def create_access_token(subject: str | Any, expires_delta: timedelta) -> str:
+    config = EnvConfig()
+
+    expire = datetime.now(timezone.utc) + expires_delta
+    to_encode = {"exp": expire, "sub": str(subject)}
+    encoded_jwt = jwt.encode(to_encode, config["secret_key"], algorithm=ALGORITHM)
+    return encoded_jwt
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    return pwd_context.verify(plain_password, hashed_password)
+
+
+def get_password_hash(password: str) -> str:
+    return pwd_context.hash(password)