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Hello all, I have been successful in getting prefect to build and run a flow on a docker container. However, I am getting an error of
```Unexpected error: ValueError('Could not infer an active Flow context.') ```
and I am struggling to find relevant information on how best to debug this. I thank you all in advance for helping!

This happens when you're trying to execute a task, but the task hasn't been assigned to a flow, so Prefect doesn't know how to run the task in relation to other tasks.

The most relevant documentation is probably <https://docs.prefect.io/core/concepts/flows.html#apis> but in short, if you're using the functional API, you should specify your task within a `with Flow() as flow:` context, e.g.
```with Flow("example") as flow:
    result = my_task()
flow.run()```
With the imperative API you have to specifically add the task to a flow, something like this:
```flow = Flow("example")
results = my_task()
flow.set_dependencies(results) 
flow.run()```

<@U01AGSHH6UR> so for reference my flow code shows
```with Flow("example",
            storage = Docker(dockerfile="/home/mblau/projects/integration/Dockerfile", ignore_healthchecks= True
)) as flow:
    main()
flow.run_config = DockerRun(image = "integration_mosaic_integration:latest")
flow.register(project_name="test")```


does `main()` have a `@task()` decorator?

Then at this point I would start looking into what's going on in `main()` , there's probably some logic in there which is leading to a task which hasn't been added to a flow. For example if `main()` is itself trying to call a function which has been decorated with `@task()` (I think this is considered an anti-pattern and instead the called task should be added explicitly to the flow).

For example, this snippet also gives me `ValueError: Could not infer an active Flow context.`
```from prefect import task, Flow

@task()
def foo():
    print("foo")

@task()
def main():
    foo()

with Flow("example") as flow:
    main()

flow.run()  # ValueError: Could not infer an active Flow context.```
So you would either need to remove the `@task()` decorator from `foo()` , which resolves the error. Or, you would restructure a bit and have the `foo()` task explicitly added to the flow, e.g.
```@task()
def foo():
    return "foo"

@task()
def main(arg):
    print(arg)

with Flow("example") as flow:
    what_to_print = foo()
    main(what_to_print)

flow.run()  # "foo"```

<@U01AGSHH6UR> awesome, that was the issue. I am fairly new to prefect and am still learning all the concepts but that works! I have other issues to resolve but that's more with the code of the file than prefect at this point, I think

Glad I could help :slightly_smiling_face: