Support for GraalPy

Community Support
1

Hi everyone,

I have a simple workflow implemented using the Python SDK which is working fine.

Now, I want to run this workflow from within GraalPy on the JVM. There are reasons why we don’t want to use the Java SDK here but run Python on the JVM via GraalPy.

After fixing several required prerequisites, I was finally able to successfully install temporalio into a GraalPy virtual environment via graalpy -m pip install temporalio (in WSL). This builds the wheel and adds it the to venv.

However, when I try to run my workflow via graalpy run_workflow.py (which works fine outside GraalPy), I get the following error:

ImportError: cannot load ~/linux-temporal-env/lib/python3.11/site-packages/temporalio/bridge/temporal_sdk_bridge.pyd: NFIUnsatisfiedLinkError: ~/linux-temporal-env/lib/python3.11/site-packages/temporalio/bridge/temporal_sdk_bridge.pyd: undefined symbol: _Py_FalseStruct

I also manually built the wheel as described in your README and installed that, but get the same error.

I’m rather new to Python and Graal, but in my understanding, the issue here is that sdk-python is using C extensions (_Py_FalseStruct) via Rust and that this is problematic in GraalPy.

So my questions are:

  1. Is there any work towards GraalVM support at Temporal?
  2. Do you see any way to make my use case work?

Any feedback is greatly appreciated!

Peter

2

Is there any work towards GraalVM support at Temporal?

No, we only support CPython at this time

Do you see any way to make my use case work?

We have not investigated GraalPy, but they do have a guide here that may help. We use PyO3 so a good first step is to see how to get a PyO3 native extension to work with GraalPy. Pydantic Core also uses PyO3, and looking at this issue, it seems they do not natively support the extension, they had to maintain custom patches for it, so I wouldn’t be surprised if Temporal would have to be treated similarly.

1 Like
3

Many thanks for the prompt reply!

What I found out by now and was confirmed by a GraalPy contributor on my GraalPy ticket is that GraalPy actually supports pyo3 >= 0.22.0.

Temporal is currently using pyo3 version 0.20.0, probably because of pyo3-asyncio which has its latest release in version 0.20.0 has been replaced by pyo3-async-runtimes.

My hope is that this is the only blocker regarding the use of GraalPy + Temporal.

Are there any plans to upgrade to pyo3 >= 0.22.0, including pythonize and pyo3-async-runtimes?

Would contributions in this direction be welcome?

4

No explicit plans, but we’d definitely be happy to. I just opened [Feature Request] Upgrade PyO3 to latest and use pyo3-async-runtimes instead of pyo3-asyncio · Issue #816 · temporalio/sdk-python · GitHub to track the effort.

Absolutely. Take a peek at the issue I just opened and mentioned above as there may be a caveat around having it use the “current” Tokio runtime instead of the implicit lazy global that pyo3-async-runtimes library may assume.