Marking internal properties as private

Providing accessors, to hint that we are accessing mutable state

src/replit/__init__.py

@@ -33,5 +33,5 @@ def clear() -> None:
 # lazily.
 def __getattr__(name: str) -> Any:
     if name == "db":
-        return LazyDB.get_instance().db
+        return LazyDB.get_db()
     raise AttributeError(name)

src/replit/database/__init__.py

@@ -24,7 +24,7 @@
 # lazily.
 def __getattr__(name: str) -> Any:
     if name == "db":
-        return LazyDB.get_instance().db
+        return LazyDB.get_db()
     if name == "db_url":
-        return LazyDB.get_instance().db_url
+        return LazyDB.get_db_url()
     raise AttributeError(name)

src/replit/database/default_db.py

@@ -26,10 +26,10 @@ class LazyDB:
     _instance: Optional["LazyDB"] = None
 
     def __init__(self) -> None:
-        self.db: Optional[Database] = None
-        self.db_url = get_db_url()
-        if self.db_url:
-            self.db = Database(self.db_url)
+        self._db: Optional[Database] = None
+        self._db_url = get_db_url()
+        if self._db_url:
+            self._db = Database(self._db_url)
             self.refresh_db()
         else:
             logging.warning(
@@ -38,11 +38,11 @@ def __init__(self) -> None:
 
     def refresh_db(self) -> None:
         """Refresh the DB URL every hour."""
-        if not self.db:
+        if not self._db:
             return
-        self.db_url = get_db_url()
-        if self.db_url:
-            self.db.update_db_url(self.db_url)
+        self._db_url = get_db_url()
+        if self._db_url:
+            self._db.update_db_url(self._db_url)
         threading.Timer(3600, self.refresh_db).start()
 
     @classmethod
@@ -52,14 +52,22 @@ def get_instance(cls) -> "LazyDB":
             cls._instance = LazyDB()
         return cls._instance
 
+    @classmethod
+    def get_db(cls) -> Optional[Database]:
+        return cls.get_instance()._db
+
+    @classmethod
+    def get_db_url(cls) -> Optional[str]:
+        return cls.get_instance()._db_url
+
 
 # Previous versions of this library would just have side-effects and always set
 # up a database unconditionally. That is very undesirable, so instead of doing
 # that, we are using this egregious hack to get the database / database URL
 # lazily.
 def __getattr__(name: str) -> Any:
     if name == "db":
-        return LazyDB.get_instance().db
+        return LazyDB.get_db()
     if name == "db_url":
-        return LazyDB.get_instance().db_url
+        return LazyDB.get_db_url()
     raise AttributeError(name)

src/replit/database/server.py

@@ -20,7 +20,7 @@ def make_database_proxy_blueprint(view_only: bool, prefix: str = "") -> Blueprin
     app = Blueprint("database_proxy" + ("_view_only" if view_only else ""), __name__)
 
     def list_keys() -> Any:
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             return "Database is not configured", 500
         user_prefix = request.args.get("prefix", "")
@@ -34,7 +34,7 @@ def list_keys() -> Any:
             return "\n".join(keys)
 
     def set_key() -> Any:
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             return "Database is not configured", 500
         if view_only:
@@ -50,7 +50,7 @@ def index() -> Any:
         return set_key()
 
     def get_key(key: str) -> Any:
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             return "Database is not configured", 500
         try:
@@ -59,7 +59,7 @@ def get_key(key: str) -> Any:
             return "", 404
 
     def delete_key(key: str) -> Any:
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             return "Database is not configured", 500
         if view_only:

src/replit/web/__init__.py

@@ -20,5 +20,5 @@
 # lazily.
 def __getattr__(name: str) -> Any:
     if name == "db":
-        return LazyDB.get_instance().db
+        return LazyDB.get_db()
     raise AttributeError(name)

src/replit/web/user.py

@@ -33,13 +33,13 @@ def set_value(self, value: str) -> None:
         Raises:
             RuntimeError: Raised if the database is not configured.
         """
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             raise RuntimeError("database not configured")
         db[self.db_key()] = value
 
     def _ensure_value(self) -> Any:
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             raise RuntimeError("database not configured")
         try:
@@ -110,7 +110,7 @@ def __getitem__(self, name: str) -> User:
         return User(username=name, prefix=self.prefix)
 
     def __iter__(self) -> Iterator[str]:
-        db = LazyDB.get_instance().db
+        db = LazyDB.get_db()
         if db is None:
             raise RuntimeError("database not configured")
         for k in db.keys():