Add a counter example using hyperdrive and Durable Objects

[ryanking13]

This example shows creating a counter using Durable Objects and storing the data into PostgreSQL-backed Hyperdrive.

1. there is one Durable objects per room that hold the counter, and multiple workers can add a counter or query the current counter from that DO.
2. DO stores the counter in 3-levels.

• In memory (caching)
• sqlite3 (per room, faster and cheaper storage)
• postgreSQL (hyperdrive, storing all counter for all rooms)

3. DO stores counter in memory first ==> then stores the value to sqlite3.

4. For every 5 seconds, it accumulates the counter and stores the value to Hyperdrive.

Screen.Recording.2026-09-02.at.6.22.12.PM.mov

[hoodmane]

Suggested change

	connection = None
	try:
	connection = self._connection()
	with self._connection() as connection:
	try:

[hoodmane]

Perhaps we should include hyperdrive in the folder name?

[hoodmane]

I tried it out and got a bunch of errors like AttributeError: module 'hashlib' has no attribute 'pbkdf2_hmac'. It says "Function only available when Python is compiled with OpenSSL."
https://docs.python.org/3/library/hashlib.html#hashlib.pbkdf2_hmac

I guess in Pyodide 0.29.x it is available, but in 314.x it has been removed.

Traceback

Exception in ASGI application after response started
Traceback (most recent call last):
  File "/session/metadata/python_modules/workers/asgi.py", line 283, in run_app
    await app(request_to_scope(req, env, state=state), receive, send)
  File "/session/metadata/python_modules/starlette/applications.py", line 96, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/session/metadata/python_modules/starlette/middleware/errors.py", line 186, in __call__
    raise exc
  File "/session/metadata/python_modules/starlette/middleware/errors.py", line 164, in __call__
    await self.app(scope, receive, _send)
  File "/session/metadata/python_modules/starlette/middleware/exceptions.py", line 63, in __call__
    await wrap_app_handling_exceptions(self.app, conn)(scope, receive, send)
  File "/session/metadata/python_modules/starlette/_exception_handler.py", line 53, in wrapped_app
    raise exc
  File "/session/metadata/python_modules/starlette/_exception_handler.py", line 42, in wrapped_app
    await app(scope, receive, sender)
  File "/session/metadata/python_modules/starlette/routing.py", line 670, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/session/metadata/python_modules/starlette/routing.py", line 690, in app
    await route.handle(scope, receive, send)
  File "/session/metadata/python_modules/starlette/routing.py", line 280, in handle
    await self.app(scope, receive, send)
  File "/session/metadata/python_modules/starlette/routing.py", line 65, in app
    await wrap_app_handling_exceptions(app, request)(scope, receive, send)
  File "/session/metadata/python_modules/starlette/_exception_handler.py", line 53, in wrapped_app
    raise exc
  File "/session/metadata/python_modules/starlette/_exception_handler.py", line 42, in wrapped_app
    await app(scope, receive, sender)
  File "/session/metadata/python_modules/starlette/routing.py", line 62, in app
    response = await f(request)
               ^^^^^^^^^^^^^^^^
  File "/session/metadata/entry.py", line 28, in get_stats
    return JSONResponse(await stub.get_stats(room))
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/session/metadata/python_modules/workers/rpc.py", line 295, in await_and_convert
    return self._convert_result(await result)
                                ^^^^^^^^^^^^
pyodide.ffi.JsException: PythonError: Traceback (most recent call last):
  File "introspection.py", line 88, in wrapper_func
    return python_to_rpc(await result)
                         ^^^^^^^^^^^^
  File "/session/metadata/room.py", line 54, in get_stats
    connection = self._connection()
  File "/session/metadata/room.py", line 111, in _connection
    return pg8000.connect(
           ~~~~~~~~~~~~~~^
        host=hd.host,
        ^^^^^^^^^^^^^
    ...<4 lines>...
        ssl_context=False,
        ^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/session/metadata/python_modules/pg8000/__init__.py", line 112, in connect
    return Connection(
        user,
    ...<11 lines>...
        startup_params=startup_params,
    )
  File "/session/metadata/python_modules/pg8000/legacy.py", line 445, in __init__
    super().__init__(*args, **kwargs)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "/session/metadata/python_modules/pg8000/core.py", line 398, in __init__
    raise e
  File "/session/metadata/python_modules/pg8000/core.py", line 391, in __init__
    self.message_types[code](_read(self._sock, data_len - 4), context)
    ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/session/metadata/python_modules/pg8000/core.py", line 618, in handle_AUTHENTICATION_REQUEST
    msg = self.auth.get_client_final().encode("utf8")
          ~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  File "/session/metadata/python_modules/scramp/core.py", line 336, in get_client_final
    self.server_signature, cfinal = _get_client_final(
                                    ~~~~~~~~~~~~~~~~~^
        self.hf,
        ^^^^^^^^
    ...<7 lines>...
        self.gs2_header,
        ^^^^^^^^^^^^^^^^
    )
    ^
  File "/session/metadata/python_modules/scramp/core.py", line 838, in _get_client_final
    salted_password = _make_salted_password(hf, password, salt, iterations)
  File "/session/metadata/python_modules/scramp/core.py", line 455, in _make_salted_password
    return hashlib.pbkdf2_hmac(
           ^^^^^^^^^^^^^^^^^^^
AttributeError: module 'hashlib' has no attribute 'pbkdf2_hmac'

[ryanking13]

I tried it out and got a bunch of errors like AttributeError: module 'hashlib' has no attribute 'pbkdf2_hmac'. It says "Function only available when Python is compiled with OpenSSL."

Right. pbkdf2_hmac comes from openssl which is not available in pyodide 314. I added md5 auth in docker compose file but adding it in the migration file sounds good.