import sqlite3 import os.path latest_db_version = 0 class Storage(object): def __init__(self, db_path): """Setup the database Runs an initial setup or migrations depending on whether a database file has already been created Args: db_path (str): The name of the database file """ self.db_path = db_path # Check if a database has already been connected if os.path.isfile(self.db_path): self._run_migrations() else: self._initial_setup() def _initial_setup(self): """Initial setup of the database""" print("Performing initial setup") # Initialize a connection to the database conn = sqlite3.connect(self.db_path) self.cursor = conn.cursor() # Sync token table self.cursor.execute("CREATE TABLE sync_token (" "token TEXT PRIMARY KEY" ")") def _run_migrations(self): """Execute database migrations""" # Initialize a connection to the database conn = sqlite3.connect(self.db_path) self.cursor = conn.cursor() print("Running migration") pass def get_sync_token(self): """Retrieve the next_batch token from the last sync response. Used to sync without retrieving messages we've processed in the past Returns: A str containing the last sync token or None if one does not exist """ self.cursor.execute("SELECT token FROM sync_token") rows = self.cursor.fetchone() if not rows: return None return rows[0] def save_sync_token(self, token): """Save a token from a sync response. Can be retrieved later to sync from where we left off Args: token (str): A next_batch token as part of a sync response """ self.cursor.execute("INSERT OR REPLACE INTO sync_token" " (token) VALUES (?)", (token,))