gotonode/calc repository overview

⁠Docker Calculator

This is an extremely simple Docker "app" that asks for two integers and prints their sum to the console.

Dockerfile contents (click here⁠ to view the file):

FROM ubuntu:16.04

WORKDIR /calc

CMD printf "First integer: "; read -r num1; printf "Second integer: "; read -r num2; printf "Their sum is: "; echo $(($num1+$num2));

⁠How to build this image?

Run this command: docker build -t calc .

You'll need to run this from the same directory that the Dockerfile is in.

This will build the Docker image with the instructions from the Dockerfile. It'll get a tag of calc.

⁠How to run the built image, creating a Docker container?

Run this command: docker run -it calc

This will create a Docker container from the image called calc.

Optionally pass the --rm argument to immediately remove the container once the calculation has been done.

⁠Sample program flow

Once a container has been created and you've gained console access to it (either by by using the attach-command or by passing the -it parameter), you can expect the program flow to look similar to the following:

First integer: 128
Second integer: 128
Their sum is: 256

You'll pass the two integers yourself as input and get their sum as output from the app.