Docker multi container with Python and mysql

This set up describes about a multi docker container setup with python and mysql.

We will create two container, one for Python App and another for Mysql and will the communication between each.

==> Create a Dockerfile for mysql-server.

#Pull Docker image.

FROM mysql:5.6

ADD nsebackup.sql /nsebackup.sql

==> Build the image

#docker build -t mysql-local-image .

==> Create the conatiner with local mouneted volume. Create the local directory on host.

#mkdir /datadir

# docker run -d --name mysql-local-server -p 3306:3306 -v  /datadir:/var/lib/mysql -e  MYSQL_ROOT_PASSWORD=xxx mysql-local-image

==> you should  able to see the container "mysql-local-server" running on the hsot using docker ps commnd.

#### Create the python app container####

==> Create a Dockerfile for python app.

# Use an official Python runtime as a parent image

FROM python:2.7-slim

# Set the working directory to /app

WORKDIR /app

# Copy the current directory contents into the container at /app

ADD . /app

# Install any needed packages specified in requirements.txt

RUN pip install -r requirements.txt

# Make port 80 available to the world outside this container

EXPOSE 8000:8000

CMD ["python", "app.py"]

==> Create app.py

from flask import Flask

import mysql.connector as mariadb

def fnconnDB():

myhost = os.environ.get('MYSQL_LOCAL_IMAGE_PORT_3306_TCP_ADDR')  #this will get the db server's IP which need to link during the docker run command. see the below docker run commnd

mariadb_connection = mariadb.connect(host=myhost,user='xxx', password='xxx',database='xxx')

return mariadb_connection

#......your codes….

#

if __name__=="__main__":

    app.run(host='0.0.0.0',port=int('8000'),debug=True,threaded=True)

==> Build the image

#docker build -t mysql-python-image .

==> run the conatiner with --link option, which will set mysql environment on python app container.

Syntax => docker run -d -p 8000:8000 --link <mysql container name>:<mysqk container image name> --name mysql-python-app mysql-python-image

#docker run -d -p 8000:8000 --link mysql-local-server:mysql-local-image --name mysql-python-app mysql-python-image