Hi everyone. I'm trying to use a repository on a gRPC server following the instructions at https://docs.dagster.io/overview/repositories-workspaces/workspaces . I have one docker image for dagit, and another one for the repository, with workspace.yaml and the repository image entrypoint like on that web page. Dagit sees the repository and lists all my pipelines and schedules, but when I try to execute a pipeline, the dagit UI just keeps spinning. There are no logs from dagit, but the repository logs the following:

Process SpawnProcess-1:
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/multiprocessing/process.py", line 297, in _bootstrap
    self.run()
  File "/usr/local/lib/python3.7/multiprocessing/process.py", line 99, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/local/lib/python3.7/site-packages/dagster/grpc/impl.py", line 184, in start_run_in_subprocess
    run_event_handler=lambda x: None,
  File "/usr/local/lib/python3.7/site-packages/dagster/grpc/impl.py", line 133, in _run_in_subprocess
    EngineEventData.in_process(pid, marker_end="cli_api_subprocess_init"),
  File "/usr/local/lib/python3.7/site-packages/dagster/core/instance/__init__.py", line 943, in report_engine_event
    check.inst_param(pipeline_run, "pipeline_run", PipelineRun)
  File "/usr/local/lib/python3.7/site-packages/dagster/check/__init__.py", line 183, in inst_param
    obj, ttype, param_name, additional_message=additional_message
  File "/usr/local/lib/python3.7/site-packages/future/utils/__init__.py", line 446, in raise_with_traceback
    raise exc.with_traceback(traceback)
dagster.check.ParameterCheckError: Param "pipeline_run" is not a PipelineRun. Got None which is type <class 'NoneType'>.

I can't find anything about this error message. Has anyone seen this? Any ideas what I could do to fix it?

Hi Jaakko - it seems like the gRPC server isn't able to load the run from your run storage when trying to execute it. Can you post your dagster.yaml for your instance? Separately, we should make this error a lot clearer (and document that the gRPC server needs to have access to your run storage).

I don't have anything in my dagster.yaml except the scheduler configuration. But you mean that dagit and the gRPC server need to share the run storage? And since I'm running them in separate docker containers, I need to either use Postgres or share a docker volume for SQLite between the containers?

Yeah, that's correct. We'll add that to the docs, apologies that wasn't clear.

No worries, thanks for the quick help! I got the pipeline execution working now

awesome - just landed a clearer error message into master to better handle this, thanks for the report!