在Heroku部署Django应用时出现ModuleNotFoundError错误求助

Hey there, let's get this Django deployment issue sorted out—this is a super common hiccup when pushing apps to Heroku, so we'll have it fixed in no time.

1. Ensure you have a requirements.txt file #

Heroku relies on this file to install all the dependencies your app needs, and right now it doesn't know it needs Django. Here's how to set it up:

• Activate your local virtual environment (if you're using one—you should be for Django projects!)
• Run this command in your project root folder:

  pip freeze > requirements.txt
  

This exports all your locally installed packages into the file. Double-check that django==[your-exact-version] (like django==3.2.19) is listed—if it's missing, add it manually.

2. Swap runserver for a production-ready server #

The python manage.py runserver command is only for local development. Heroku recommends using Gunicorn as your WSGI server:

• Install Gunicorn locally first:

  pip install gunicorn
  

• Update your requirements.txt again with pip freeze > requirements.txt to include Gunicorn
• Create a file named Procfile (no file extension) in your project root, and add this line:

  web: gunicorn your_project_name.wsgi --log-file -
  

  Replace your_project_name with the name of the folder that holds your wsgi.py and settings.py files.

3. Push the updates to Heroku #

Run these Git commands to send your new configuration to Heroku:

git add requirements.txt Procfile
git commit -m "Add dependencies and production server config for Heroku"
git push heroku master

Quick troubleshooting if it still fails #

• Did you forget to activate your virtual environment before running pip freeze? If you used global packages, your requirements.txt might not have the right versions.
• Make sure you're pushing the correct Git branch—if you're working on a branch other than master, use git push heroku your-branch-name:master.

Your original error log for reference:

2018-05-03T14:35:40.682441+00:00 heroku[web.1]: Starting process with command `python manage.py runserver`
2018-05-03T14:35:41.960741+00:00 app[web.1]: Traceback (most recent call last):
2018-05-03T14:35:41.960765+00:00 app[web.1]: File "manage.py", line 8, in <module>
2018-05-03T14:35:41.960858+00:00 app[web.1]: from django.core.management import execute_from_command_line
2018-05-03T14:35:41.960872+00:00 app[web.1]: ModuleNotFoundError: No module named 'django'

内容的提问来源于stack exchange，提问作者Dimmy Magalhães