Pros and Cons of Docker

Docker is gaining traction in the software development industry at such a phenomenal rate that more and more teams are adopting it into their processes. Keeping everyone on the same page with technology stacks has become increasingly difficult as the technology itself becomes more complex. There are countless technical articles on Medium extolling the virtues of Docker and how it can help mitigate these types of problems. Now that I have been using Docker as a local development environment for over a year, I’d like to talk about the pros and cons of making the switch.

Pros

Docker on Mac and Windows are better than ever.

Docker is getting more and more mature by the day, especially as more developers are turning to it for the development and production environments. Docker for Mac and Docker for Windows reduces much of the complexity of leveraging Docker on non-Linux environments through abstraction. It now works as simply as any other application in your environment -- install it in the same fashion as your other tools like your text editor and browser -- and you are off to the races.

Docker gives you consistency across your team.

Another aspect of Docker that I love is the reliability that you have the same setup as your team. This is great for a couple reasons: there is so much value in being able to run with the assumption that your entire team is using the same setup, and it enables you to run scripts and processes that will empower your entire development team to perform common operations with a simple command.

Docker eases the pain of debugging environments.

Our processes used to consist of having to track down pages and pages of documentation, only to find that this documentation is out of date and needs to be updated, so where do I end up? Spending days pouring over posts on Stack Overflow trying to find out how to update the services I’ve been using on my machine, which are probably different than everyone else’s on my team. So each developer needs to do that exploration independently because each solution will be slightly different. With Docker, you can easily isolate and eliminate environment issues across your team without needing to know how someone’s machine is setup.

Interesting avenues of automation open up with Docker.

As someone who is fascinated with automation, I’ve always tried to find shortcuts to doing the boring, repetitive jobs that take too much time to do manually. Have to update the database on the development server? Ok, great, you just need to look up the password for the development server (which could be any of 4 different places, depending on the project) and once that’s done, you realize you also don’t have the password for the live or staging environment, so you have to wait 3 days for the call from the IT firm that manages that server to give you credentials. With a Docker infrastructure, you can easily transfer the environment (with some small utility changes) to the CI system of choice. Most of the prominent CI solutions available today integrate well with Docker.

Docker speeds up the provisioning process.

You can avoid wild goose chases by providing all you need from within the docker container, potentially using a set of shared ssh keys, or requiring users to use personal keys on an identity service (best case scenario, but impractical for some teams).

Docker for Mac and Windows is more stable than ever before.

Even with its rapid development cycle, the team working on Docker for Mac have done an exceptional job keeping the platform as stable as possible. This is important because the app auto-updates. Despite the fact that I am on the Edge version of the platform (which seems to update weekly), I have only had one issue that caused me to have to rollback. I ended up losing a day of development time to this bug, but after I found a way to rollback gracefully, the following day there was a bugfix released to remedy the issue. Despite this one small glitch, I still stand by Docker because I had more conflicts when I was relying on Homebrew or compiling binaries for services manually.

The Docker community is huge and resources are plentiful.

There are a huge number of images (last count on Docker Hub has it at 100,000+) to pull from for free from Docker Hub. These images are blueprints to creating your containers which will house all of your services for your application. You will find varying success on the level of documentation each of these images provide, but for the most part they are ready to plug into your application.