Can't access flask app which is inside docker container

Question

I can not request to my flask app inside docker container. It doesn't responding.

there is my flask app file:

import json
from flask import Flask, jsonify
from flask import request

from trained_model import predict
app = Flask(__name__)

@app.route("/", methods=['POST'])
def main():
    res = []

    for obj in request.json:
        item = str(obj['item'])
        print item
        predicted = predict(item)
        print predicted
    res.append({'item': item, 'correct': predicted})

    return json.dumps({'results': res})

if __name__ == "__main__":
    app.run(host='0.0.0.0')

there is my dockerfile:

FROM tensorflow/tensorflow

# Create app directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

# Bundle app source
COPY . /usr/src/app

RUN sh docker_install.sh

EXPOSE 5000
ENTRYPOINT ["python"]
CMD ["api.py"]

there is my docker run command:

sudo docker run -p 5000:5000 -d my-image

when I try to send post request it doesn't work.

Answer 1

I've had success with flask run --host=0.0.0.0. Somehow that seems to be different than app.run(host='0.0.0.0'), but I don't know why. See https://stackoverflow.com/a/43015007/9484954

Answer 2

flask run --host=0.0.0.0 is useful in case you want to access flask server externally. I had similar kind of issue when I was running flask app inside docker container. Though I modified my flask app and added app.run(host:'0.0.0.0'), server was running but I can not access it in browser.then I ran flask server externally by providing same port o.o.o.o.

Answer 3

I was having the same problem. I did app.run(debug=True,host='0.0.0.0') from app.run() and it worked. Not sure what was the issue with the app.run() though