An example of what I mean, using the following structure:

my_project/
├── README.txt
├── __init__.py
├── requirements.txt
├── setup.py
├── etl
│   ├── __init__.py
│   ├── foo
│   │   ├── __init__.py
│   │   ├── foo_flow.py
│   │   ├── config
│   │   │   ├── __init__.py
│   │   │   └── foo_config.py
│   ├── shared
│   │   ├── __init__.py
│   │   └── sftp_utils.py
│   └── bar
│       ├── __init__.py
│       ├── bar_flow.py
│       ├── config
│       │   ├── bar_config.py
│       └── test
│           ├── __init__.py
│           └── test_bar_flow.py
├── .venv
├── start_agent.bat

 I want to have two flows, 

foo_flow.py

 and 

bar_flow.py

, each of which use some common logic imported from 

sftp_utils.py

, and have one agent launched from 

start_agent.bat

 which can trigger both of the flows. My main pain points are: • what to put into 

setup.py

 so that running 

pip install -e .

 in the root dir allows scripts to import from each other • what importing syntax to use in (e.g.) 

foo_flow.py

 to get logic from 

sftp_utils.py

Currently when I register the flow with Prefect Server, then start the local agent with 

--show-flow-logs

 , the CLI spams error messages, starting with 

ModuleNotFoundError: No module named 'setuptools._distutils'

 then repeating this over and over:

tornado.application - ERROR - Exception in callback <bound method Nanny.memory_monitor of <Nanny: None, threads: 4>>
Traceback (most recent call last):
  File "c:\my_project\.venv\lib\site-packages\tornado\ioloop.py", line 907, in _run
    return self.callback()
  File "c:\cmy_project\.venv\lib\site-packages\distributed\nanny.py", line 414, in memory_monitor
    process = self.process.process
AttributeError: 'NoneType' object has no attribute 'process'

When using local storage it’s important to note that the agent must be running in a Python environment with the same packages as your flow.run() environment

e.g. I ran the agent in a python environment where I had run

pip install -e .

with my module. Using docker storage would allow you to setup an environment alongside your flow so I recommend doing that in production but it depends on your setup!

@Greg Roche when you get a chance let me know if this helped! It’d be a nice thing to flesh out for other users if that is the case.

Michael, your example has helped out so much, thanks very much for taking the time to put it together! In case it matters for anyone else coming across this, it seems like my main mistake was to have the logic for registering (e.g.) the

foo

flow in

foo_flow.py

, then running

python etl\foo\foo_flow.py

from the root folder to register the flow in Prefect Server, rather than having a

register.py

file in the project root folder to handle the flow registration. In addition I didn't have my

setup.py

file configured correctly by not specifying the

etl

folder as a package. This meant I had to resort to PYTHONPATH hacks and other silliness to try to import from sibling folders, this way is so much cleaner and more elegant and extensible. Michael, please let me know a way to buy you a couple of beers remotely as thanks :D

@Michael Adkins I am getting this error, because I believe I am unable to import the flows folder as part of my Docker build. What should I be doing as part of my Docker build process?

Step 6/10 : RUN mkdir -p /opt/prefect/

 

---> Using cache

 

---> 9b9f5132ea1a

Step 7/10 : COPY z-etl-flow.flow /opt/prefect/flows/z-etl-flow.prefect

 

---> fb8c3ce3bda9

Step 8/10 : COPY z-mr-flow.flow /opt/prefect/flows/z-mr-flow.prefect

 

---> 08102086f4ef

Step 9/10 : COPY healthcheck.py /opt/prefect/healthcheck.py

 

---> 725cca0c7872

Step 10/10 : RUN python /opt/prefect/healthcheck.py '["/opt/prefect/flows/z-etl-flow.prefect", "/opt/prefect/flows/z-mr-flow.prefect"]' '(3, 7)'

 

---> Running in 0edd438d422e

Beginning health checks...

System Version check: OK

/opt/prefect/healthcheck.py:147: UserWarning: Flow uses module which is not importable. Refer to documentation on how to import custom modules <https://docs.prefect.io/api/latest/storage.html#docker>

 

flows = cloudpickle_deserialization_check(flow_file_paths)

Traceback (most recent call last):

 

File "/opt/prefect/healthcheck.py", line 147, in <module>

  

flows = cloudpickle_deserialization_check(flow_file_paths)

 

File "/opt/prefect/healthcheck.py", line 40, in cloudpickle_deserialization_check

  

flows.append(cloudpickle.load(f))

ModuleNotFoundError: No module named 'prefectflows'

Removing intermediate container 0edd438d422e

The command '/bin/sh -c python /opt/prefect/healthcheck.py '["/opt/prefect/flows/z-etl-flow.prefect", "/opt/prefect/flows/z-mr-flow.prefect"]' '(3, 7)'' returned a non-zero code: 1

Traceback (most recent call last):

 

File "register_flows.py", line 36, in <module>

  

storage = storage.build()

 

File "/Users/sagungargs/Documents/portcast/flows/.venv/lib/python3.7/site-packages/prefect/storage/docker.py", line 360, in build

  

self._build_image(push=push)

 

File "/Users/sagungargs/Documents/portcast/flows/.venv/lib/python3.7/site-packages/prefect/storage/docker.py", line 428, in _build_image

  

"Your docker image failed to build! Your flow might have "

ValueError: Your docker image failed to build! Your flow might have failed one of its deployment health checks - please ensure that all necessary files and dependencies have been included.