Skip to main content

Lab #7: Create a Docker image with EXPOSE instruction

Pre-requisite:​

Tested Infrastructure​

Platform Number of Instance Reading Time
Play with Docker 1 5 min

Pre-requisite​

  • Create an account with DockerHub
  • Open PWD Platform on your browser
  • Click on Add New Instance on the left side of the screen to bring up Alpine OS instance on the right side

Assignment:​

  • Create an image with expose instruction
  • Create hello.py
  • Create dockerfile
  • Build dockerfile
  • Run application

Creating directory​

mkdir pythonexposeapp 
cd pythonexposeapp

Creating hello.py​

vi hello.py

from flask import Flask
app = Flask(__name__)

@app.route("/")
def hello():
    return "welcome to Dockerlabs!! successfully done !!"

if __name__ == "__main__":
    app.run()

Creating Dockerfile​

vi Dockerfile

FROM python:3.5

# Update and install dependencies
RUN apt-get update
RUN pip install Flask

# Add code
ADD . /opt/webapp/

# Set the working directory
WORKDIR /opt/webapp

# Set environment variables
ENV FLASK_APP=hello.py

# Expose the application's port
EXPOSE 5000

# Run the application
CMD ["flask", "run", "--host=0.0.0.0"]


Building Dockerfile​

 docker build -t pythonapp:v1 .

Running Docker image​

sangam$ docker run -p 5000:5000 pythonapp:v1
 * Serving Flask app "hello.py"
 * Environment: production
   WARNING: This is a development server. Do not use it in a production deployment.
   Use a production WSGI server instead.
 * Debug mode: off
 * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)
172.17.0.1 - - [17/Aug/2019 12:21:20] "GET / HTTP/1.1" 200 -
172.17.0.1 - - [17/Aug/2019 12:21:20] "GET /favicon.ico HTTP/1.1" 404 -

By now, the application should be accessible http://0.0.0.0:5000/

Contibutor

Sangam Biradar

Next >> VOLUME_instruction