Docker

By Carlos Luevano - github: @Clue355

The entire development environment, including OS, libraries, and dependencies, is encapsulated in the container. In a way, a Docker container can be thought of as a lunchbox that contains a full meal, or everything you need to run your application.

It can be taken anywhere and run on any computer. Everyone will be running the same application when building and testing. Dependency versions will be defined, which eliminates version conflicts and the need to manually install dependencies, and even computing resources.

When setting up Docker in an application, you would make a file known as an image. You can think of an image as a list of ingredients needed to make your meal for your lunchbox.

The image contains the specifications you need for the environment. Then, from that file, you would run a command to set up a Docker container and build the development environment from that image. After that, you would be able to access the running application from a local host.

Multiple instances of your application can be created to handle more load. These instances can be created on a single server. Each runs isolated, and limits are dictated by the server's hardware resources.

Without Docker:

• Setups might be inconsistent, meaning different OS, and software versions.
• We may come across dependency conflicts.
• Setup can be more time-consuming as you have to install everything and make sure all software versions are the same.
• It doesn't have the isolation Docker has, meaning the application shares resources with other applications.