宿主机访问docker flask报错拒绝连接

1.错误代码

[root@localhost testflask]# cat app.py
import os

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello():
    provider = str(os.environ.get('PROVIDER', 'world'))
    return 'Hello world'

if __name__ == '__main__':
    # Bind to PORT if defined, otherwise default to 5000.
    port = int(os.environ.get('PORT', 5000))

2.宿主机本地curl会报错，但是容器内部可以curl正常显示

答疑链接：https://blog.csdn.net/lixiaoyu101/article/details/84565316

3.修改后代码

[root@localhost testflask]# cat app.py
import os

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello():
    provider = str(os.environ.get('PROVIDER', 'world'))
    return 'Hello world'
if __name__ == '__main__':
    # Bind to PORT if defined, otherwise default to 5000.
    port = int(os.environ.get('PORT', 5000))
    app.run(host='0.0.0.0', port=5000)


# Dockfile
[root@localhost testflask]# cat Dockerfile
FROM python:3.6.5           
COPY . /opt
RUN pip3 install --no-cache-dir -r /opt/requirements.txt
CMD ["python", "/opt/app.py"]