Containerization of application with Docker

[tenongene]

• I wrote the Dockerfile for building the application image. I used a slim node base image available in docker hub.
• Copied the current directory to the image working directory which I named as "app".
• Ran "npm install" so that all the application dependencies from the package.json file got included with the image.
• Exposed port 7272 which is the application port as written in Express.
• The command was "node index.js" which will start the application in the container.
• Built the image by running "docker build -t tenongene/quotegen ." in the current directory.
• Ran "docker push tenongene/quotegen" to push the image to docker hub.

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Application image now in Docker Hub.