Updated config.py with additional environment variables, validation, and structured settings

backend/config.py

@@ -1,12 +1,32 @@
 from pydantic_settings import BaseSettings, SettingsConfigDict
+from pydantic import field_validator
+
 
 class Settings(BaseSettings):
-    DATABASE_URL : str
-    ## add the variable and variable type in .env file
-    ## Note: var name should match that in .env file
-    setting = SettingsConfigDict(
-        env_file= "backend/.env",
-        extra= "ignore"
+    # Database
+    DATABASE_URL: str
+
+    # Application
+    DEBUG: bool = False
+    SECRET_KEY: str
+    API_VERSION: str = "v1"
+
+    # Logging
+    LOG_LEVEL: str = "INFO"
+
+    # Pydantic Settings configuration
+    model_config = SettingsConfigDict(
+        env_file="backend/.env",
+        extra="ignore"
     )
 
-setting = Settings()
+    # Validator for database URL
+    @field_validator("DATABASE_URL")
+    def check_db_url(cls, v: str) -> str:
+        if not v.startswith("postgresql://"):
+            raise ValueError("DATABASE_URL must start with 'postgresql://'")
+        return v
+
+
+# Global settings instance
+setting = Settings()