Python/Docker ImportError: cannot import name 'json' from itsdangerous-CodePudding

I am trying to get a Flask and Docker application to work but when I try and run it using my docker-compose up command in my Visual Studio terminal, it gives me an ImportError called ImportError: cannot import name 'json' from itsdangerous. I have tried to look for possible solutions to this problem but as of right now there are not many on here or anywhere else. The only two solutions I could find are to change the current installation of MarkupSafe and itsdangerous to a higher version: https://serverfault.com/questions/1094062/from-itsdangerous-import-json-as-json-importerror-cannot-import-name-json-fr and another one on GitHub that tells me to essentially change the MarkUpSafe and itsdangerous installation again https://github.com/aws/aws-sam-cli/issues/3661, I have also tried to make a virtual environment named veganetworkscriptenv to install the packages but that has also failed as well. I am currently using Flask 2.0.0 and Docker 5.0.0 and the error occurs on line eight in vegamain.py.

Here is the full ImportError that I get when I try and run the program:

veganetworkscript-backend-1  | Traceback (most recent call last):
veganetworkscript-backend-1  |   File "/app/vegamain.py", line 8, in <module>
veganetworkscript-backend-1  |     from flask import Flask
veganetworkscript-backend-1  |   File "/usr/local/lib/python3.9/site-packages/flask/__init__.py", line 19, in <module>
veganetworkscript-backend-1  |     from . import json
veganetworkscript-backend-1  |   File "/usr/local/lib/python3.9/site-packages/flask/json/__init__.py", line 15, in <module>
veganetworkscript-backend-1  |     from itsdangerous import json as _json
veganetworkscript-backend-1  | ImportError: cannot import name 'json' from 'itsdangerous' (/usr/local/lib/python3.9/site-packages/itsdangerous/__init__.py)
veganetworkscript-backend-1 exited with code 1

Here are my requirements.txt, vegamain.py, Dockerfile, and docker-compose.yml files:

requirements.txt:

Flask==2.0.0
Flask-SQLAlchemy==2.4.4
SQLAlchemy==1.3.20
Flask-Migrate==2.5.3
Flask-Script==2.0.6
Flask-Cors==3.0.9
requests==2.25.0
mysqlclient==2.0.1
pika==1.1.0
wolframalpha==4.3.0

vegamain.py:

# Veganetwork (C) TetraSystemSolutions 2022
# all rights are reserved.  
# 
# Author: Trevor R. Blanchard Feb-19-2022-Jul-30-2022
#

# get our imports in order first
from flask import Flask # <-- error occurs here!!!

# start the application through flask.
app = Flask(__name__)

# if set to true will return only a "Hello World" string.
Debug = True

# start a route to the index part of the app in flask.
@app.route('/')
def index():
    if (Debug == True):
        return 'Hello World!'
    else:
        pass

# start the flask app here --->
if __name__ == '__main__':
    app.run(debug=True, host='0.0.0.0')

Dockerfile:

FROM python:3.9
ENV PYTHONUNBUFFERED 1
WORKDIR /app
COPY requirements.txt /app/requirements.txt
RUN pip install -r requirements.txt
COPY . /app

docker-compose.yml:

version: '3.8'
services:
  backend:
    build:
      context: .
      dockerfile: Dockerfile
    command: 'python vegamain.py'
    ports:
      - 8004:5000
    volumes:
      - .:/app
    depends_on:
      - db

#  queue:
#    build:
#      context: .
#      dockerfile: Dockerfile
#    command: 'python -u consumer.py'
#    depends_on:
#      - db

  db:
    image: mysql:5.7.22
    restart: always
    environment:
      MYSQL_DATABASE: admin
      MYSQL_USER: root
      MYSQL_PASSWORD: root
      MYSQL_ROOT_PASSWORD: root
    volumes:
      - .dbdata:/var/lib/mysql
    ports:
      - 33069:3306

How exactly can I fix this code? thank you!

CodePudding user response：

The import failure seems to be related with the latest release version of the package itsdangerous. Check the latest releases here

In my case, I made it work by explicitly adding the package dependency itsdangerous==2.0.1 in my requirements.txt file.

To make changes effective, update your virtual environment to reflect the new requirements.txt.

CodePudding user response：

I was facing the same issue while running docker containers with flask.

I downgraded Flask to 1.1.4 and markupsafe to 2.0.1 which solved my issue.

Check this for reference.

CodePudding user response：

The answer of @JoeBigToe works for me, however just notice that in its post there is a misprint in the package name (I cannot comment there since I have not 50 reputation score).

Of course, it should be itsdangerous==2.0.1 and not itsdategerous==2.0.1.

CodePudding user response：

The root of this issue appears to be that Flask 2.0.0 is unsupported. Try using the latest version of Flask.

https://github.com/pallets/itsdangerous/issues/289

As of today, the latest version is 2.1.0:

pip install Flask=2.1.0