no idea

solid/open_close/users.py

@@ -0,0 +1,45 @@
+import sqlite3
+
+
+class User:
+    def __init__(self, name: str):
+        self.name = name
+
+
+class UserStorage:
+    def __init__(self):
+        self._memory: list[User] = []
+
+    def save(self, user: User) -> None:
+        self._memory.append(user)
+
+    def get(self, name: str) -> User | None:
+        for user in self._memory:
+            if user.name == name:
+                return user
+
+    def get_if_name_starts_by_a(self, name: str) -> User | None:
+        if name.lower().startswith('a'):
+            return self.get(name)
+
+
+class SQliteUserStorage(UserStorage):
+    def __init__(self, conn: sqlite3.Connection):
+        self._conn = conn
+
+    @classmethod
+    def create(cls, url: str) -> 'SQliteUserStorage':
+        conn = sqlite3.connect(url)
+        conn.execute('''CREATE TABLE IF NOT EXISTS users(name TEXT UNIQUE NOT NULL)''')
+        return cls(conn)
+
+    def save(self, user: User) -> None:
+        self._conn.execute(
+            '''INSERT INTO users(name) VALUES (?)''', (user.name, )
+        )
+
+    def get(self, name: str) -> User | None:
+        res = self._conn.execute("""SELECT name FROM users WHERE name = ?""", (name, )).fetchone()
+        if res is None:
+            return None
+        return User(res[0])