Cannot import other functions with Python API

[ninest]

After seeing this comment, I learned that to import a function in your Python API, you have to put an underscore before the file name.

I tried this method but it doesn't seem to work. I have _utils/common.py inside my api/ directory.

My index.py looks like this:

from flask import Flask, Response
from _utils.common import VAR
app = Flask(__name__)

print(VAR)

...

When I try to visit any API route, I get this error:

 File "./api/index.py", line 2, in <module>
    from _utils.common import VAR
ModuleNotFoundError: No module named '_utils'

Everything works fine when I run the code with python3 api/index.py, but using vercel dev causes this error. It comes as a 502: bad gateway error.

Is there an official example I can refer to?

[kittinan]

@ninest Did you found solution to import file?

[ninest]

Sorry, no. I haven't tried anything since I posted this

[kittinan]

@ninest I found solution.

Original project structure (Not working)

ROOT PROJECT
  |
  |
 API
  |
  | -- util
  |      | -- spotify.py
  |
  | -- index.py

# index.py

from util import spotify

I moved /api/util folder to root path project /util. index.py can import correctly when running on Vercel serverless function

[ernesto]

That´s no make sense... Why with

"functions": {
    "api/index.py": {
      "includeFiles": "api/_utils.py"
    }
}

Doesnt works?

[GoulartNogueira]

@ernesto
I believe "includeFiles" means files used to generate APIs.
It's not about import.

[shimahi]

@ninest

If you set vercel.json on project root directory, try to write import phrase to refer absolute path from vercel.json, or relative path from index.py .

from api.util.spotify import 〜〜〜

or

from .util.spotify import 〜〜〜

cf. vercel.json is like this.

{
  "functions": {
    "api/index.py": {
      "includeFiles": "_utils/**"
    }
  },
  "routes": [{ "src": "/", "dest": "api/index.py" }]
}

[FVitor7]

Solution?

[ninest]

If I'm not wrong, you can import the python functions as your normally would in a python program, no extra steps needed. I'll try making an example

[FVitor7]

I would appreciate your example, I'm trying everything and I can't import other .py files

[ninest]

Actually, I do have an example here

https://github.com/ninest/ippt

It's a fitness test score calculator. The score calculation is in the calculator folder. In the api folder, I'm using flask, and importing functions from calculator. See if it helps solve your problem

[FVitor7]

It worked!!! thank you so much

[pado31]

I have a similar problem. My project is structured as follows:

ROOT PROJECT
  |
  |
 src
  |
  | -- util
  |      | -- __init__.py
  |      | -- service.py
  |
  | -- server.py
  | -- vercel.json
  | -- requirements.txt

Inside server.py I have the following code:

from flask import Flask
from util.service import Updater

app = Flask(__name__)

@app.route("/api/v1/update/")
def getUpdate():
    return Updater.update_values()

And my vercel.json:

{
    "version": 2,
    "builds": [
        {
            "src": "src/server.py",
            "use": "@vercel/python"
        }
    ],
    "routes": [
        {
            "src": "/",
            "dest": "src/server.py"
        }
    ]
}

Vercel gives me the following error:
[ERROR] Runtime.ImportModuleError: Unable to import module 'vc__handler__python': No module named 'util'

Locally my project runs correctly. Moreover, if in server.py I don't use any import and I simply write return "Hello, world!", the api works so I suppose that the configuration is right.

Any solution? Thank you!

[warmachine028]

Yes I am also having the same error

[tanw89]

Same issue too. Anyone found a workaround?

[deepakstark01]

{
  "functions": {
    "api/index.py": {
      "includeFiles": [
        "_utils/**",
        "other_functions/**"
      ]
    }
  },
  "routes": [{ "src": "/", "dest": "api/index.py" }]
}

[deepakstark01]

{
  "routes": [
    {
      "src": "/api/(.*)",
      "dest": "api/index.py"
    }
  ]
}

[Chaoyingz]

You can add the environment variable PYTHONPATH to help the Python interpreter locate this module.
Add this to vercel.json:

"env": {
    "PYTHONPATH": "api/"
}

[Upendra-Thunuguntla]

Either do this or just add same in the Env Variable

[Marvy101]

"env": {
    "PYTHONPATH": "api/"
}

Doing this worked for me.

[FrancescoSaverioZuppichini]

can somehow share a working solution?

[deepakstark01]

yes