Dockerize Your Projects - A Brief Introduction to Containerization

A brief introduction to Docker and an illustration of an application containerization.

1. Dockerize Your Projects
A Brief Introduction to Containerization
Sawood Alam <@ibnesayeed>
Old Dominion University, Norfolk, Virginia - 23529 (USA)

2. Docker
●Application container
●Packages dependencies
●Isolates applications
●Lighter than a virtual machine
●Open-source
Host OS
Host OS
Docker Engine
Bins/Libs
App B
Bins/Libs
App A
Container

3. Dockerization
Dockerfile ImageBuild Run Container

4. Example
#!/usr/bin/env python

import sys
import requests
from bs4 import BeautifulSoup

r = requests.get(sys.argv[-1])
data = r.text
soup = BeautifulSoup(data)
for link in soup.find_all("a"):
print(link.get("href"))

FROM python
LABEL maintainer="Sawood Alam <@ibnesayeed>"

RUN pip install beautifulsoup4
RUN pip install requests
ADD main.py /app/
WORKDIR /app
RUN chmod a+x main.py

ENTRYPOINT ["./main.py"]

main.py Dockerfile

5. Try It
me@thishost$ ls
>> Dockerfile main.py
# Build an image from the Dockerfile (change "ibnesayeed" with your Docker ID)
me@thishost$ docker image build -t ibnesayeed/urlextractor .
>> Layered docker images...
# Run a container from the locally built image
me@thishost$ docker container run ibnesayeed/urlextractor https://odu.edu/compsci
>> Extracted links…
# Push the image to the registry
me@thishost$ docker image push ibnesayeed/urlextractor
# Log in to a different host
me@thishost$ ssh you@otherhost
# Run a container on the other host using the image in the registry
you@otherhost$ docker container run ibnesayeed/urlextractor https://odu.edu/compsci
>> Pull the image from the registry (if not cached already)
>> Extracted links...

6. References
●https://www.docker.com/
●https://docs.docker.com/
●https://training.docker.com/
●http://training.play-with-docker.com/
●https://hub.docker.com/
●https://hub.docker.com/r/ibnesayeed/urlextractor/
●https://gist.github.com/ibnesayeed/de0eaed5daaeae29e61c938206808d64