change that GameplayDatabase can have different backends, sqlite and postgresql with a Template example backend

server/bootstrap.py

@@ -23,11 +23,13 @@ def build_server_from_env(default_snake_type:str) -> Server:
   metrics_ttl_sec = env_int('METRICS_TTL_SEC', 900) if metrics_ttl_sec_raw is not None else None
 
   gameplay_db_enabled = env_bool('GAMEPLAY_DB_ENABLED', True)
+  gameplay_db_backend = os.environ.get('GAMEPLAY_DB_BACKEND', 'sqlite')
   gameplay_db_path = os.environ.get(
     'GAMEPLAY_DB_PATH',
     os.path.join(data_path, 'data', 'database', 'gameplay.sqlite3'),
   )
   gameplay_db_busy_timeout_ms = env_int('GAMEPLAY_DB_BUSY_TIMEOUT_MS', 5000)
+  gameplay_db_pg_dsn = os.environ.get('GAMEPLAY_DB_PG_DSN', None)
 
   server = Server(
     data_path=data_path,
@@ -39,8 +41,10 @@ def build_server_from_env(default_snake_type:str) -> Server:
     metrics_redis_url=metrics_redis_url,
     metrics_ttl_sec=metrics_ttl_sec,
     gameplay_db_enabled=gameplay_db_enabled,
+    gameplay_db_backend=gameplay_db_backend,
     gameplay_db_path=gameplay_db_path,
     gameplay_db_busy_timeout_ms=gameplay_db_busy_timeout_ms,
+    gameplay_db_pg_dsn=gameplay_db_pg_dsn,
   )
 
   if env_bool('STORE_GAME_HISTORY'):