使用docker run添加数据文件

Question

I want to add a python script to a docker container. This script processes a data file that I provide when I run the container. I could not figure out how to do that so I would appreciate some help (I do not want to add the data.txt file to the container). I understand that I could send the file to a REST interface with curl but if possible I'd like a simpler solution.

(I would be great if the solution works on ECS, too. But I do not yet understand the implications of that.)

Dockerfile:

FROM centos:6

RUN yum -y update
RUN yum -y install epel-release && yum clean all
RUN yum -y install python-pip && yum clean all

ADD . /myapp
WORKDIR /myapp

# install requirements
RUN pip install -r requirements.txt
# install 
#RUN pip install .

CMD ["python","./app.py", "/data.txt"]

script:

import sys


def print_out(datafile):
    with open(datafile, 'r') as dfile:
        for line in dfile:
            print line.strip()


def main():
    datafile = sys.argv[1]
    print_out(datafile)


if __name__ == '__main__':
    main()

data.txt:

Bob
Steve
Marvin
Paul

run the container (does not work like that)

$ docker run myapp data.txt

Answer 1

Use a host volume (aka bind mount) to map your script (assuming it's called app.py) and data.txt into the container. Place them both in the same directory and then run:

docker run -v `pwd`:/myapp myapp python app.py data.txt

From that directory to map the current directory to /myapp (overlaying whatever is inside the image at that location). If you're on Docker for Windows/Mac, make sure you're under the c:/Users or /Users directory.