Heroku本地失败，没有错误消息

Question

I'm trying to get a flask structure up and running with Heroku following their guide: https://devcenter.heroku.com/articles/getting-started-with-python-o

but I'm encountering a weird problem, following the guide, I get the following error when running heroku local :

forego | starting web.1 on port 5000
web.1  | Traceback (most recent call last):

with no additional messages. I'm on windows 7 64bit and tried running it from both gitbash and cmd with and without "run as administrator ", but nothing changes.

My Procfile looks like this:

web: gunicorn main:app --log-file -

folder structure is pretty much the standard:

.git/
static/
venv/
main.py
Procfile

and main.py is:

import os
from flask import Flask
app = Flask(__name__)

@app.route('/')
def root():
    return 'hello world'

Now when I tried calling app.run to run flask manually, it worked fine with no problems.. Any idea to what might be causing this?

Answer 1

Apparently, this is the behavior if your procfile is blank. Check that and reset it if needed.