Cannot import InMemoryPushNotifier

[luisangelico]

What happened?

When trying to run LangGraph server I cannot import InMemoryPushNotifier

Relevant log output

(.venv) luishenriqueangelico@Mac app % python3 __main__.py      
Traceback (most recent call last):
  File "/Code/a2a-samples/samples/python/agents/langgraph/app/__main__.py", line 11, in <module>
    from a2a.server.tasks import InMemoryPushNotifier, InMemoryTaskStore
ImportError: cannot import name 'InMemoryPushNotifier' from 'a2a.server.tasks' (/Code/a2a-samples/.venv/lib/python3.13/site-packages/a2a/server/tasks/__init__.py)

Code of Conduct

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[PVGunavardhan]

ImportError: cannot import name 'InMemoryPushNotifier' from 'a2a.server.tasks'

Check the version of a2a-sdk, you need to have version 0.2.8 installed.

[luisangelico]

ImportError: cannot import name 'InMemoryPushNotifier' from 'a2a.server.tasks'

Check the version of a2a-sdk, you need to have version 0.2.8 installed.

I'm using 0.2.11 version. Should I hard code v0.2.8?

[PVGunavardhan]

I'm using 0.2.11 version. Should I hard code v0.2.8?

Yes you need to use the v0.2.8 for the import to work, I was also getting the same error earlier and 'InMemoryPushNotifier' is not present in the latest version. I'm not sure about the latest version migration changes that need to be done but I installed the same packages mentioned in 'pyproject.toml' file using uv package manager and it worked fine.

Aren't you installing the dependencies using uv package manager?

[luisangelico]

I'm using pip.

[luisangelico]

0.2.8 still doesn't work

[PVGunavardhan]

0.2.8 still doesn't work

Use 'python -m app' command, it is working with me.

[luisangelico]

It worked, tks!

[thomas-ancel]

I'm not sure about the latest version migration changes that need to be done but I installed the same packages mentioned in 'pyproject.toml' file using uv package manager and it worked fine.

Here are the changes required.
a2aproject/a2a-python#212