This is the first article in a series of developing for WordPress in a DevOps friendly way. The other articles:
- Introduction to WordPress and DevOps
- Developing with WordPress and Vagrant
- Grunt Automation for WordPress developers
- WordPress configuration management
In this post, we’ll talk about what DevOps means to WordPress developers. Can DevOps deal with WordPress and perhaps more important, can the WordPress community deal with DevOps?
So what is DevOps? Wikipedia describes DevOps as a development method that emphasizes collaboration, integration and automation between software development teams and other IT professionals. To understand what that means in practical terms it’s easier to look back at how IT used to work at many companies. There’d be two teams of technical people, one team would focus on developing web stuff or internal applications. The other team would focus on maintaining servers, network infrastructure, look after backups among other things, commonly referred to as operasions. The communication between them was often kept at a “need to know basis” and blame storming would be common. Not everywhere, but often enough for problems to arise.
The introduction of DevOps as a concept was first and foremost a mindset change. With better collaboration between development and operations came better understanding of how each part of the equation works. Better understanding also quickly led to better internal processes and soon thereafter, better tools and more automation. Today the term DevOps often means a mix of these things. DevOps can mean the process or method of getting internally developed software into production. DevOps can sometimes refer to a set of tools to help that work. Or in some places DevOps is simply the new name for the part of IT department that deals with these issues.
In the the context of WordPress, we need to think of DevOps primarily as automation. A large part of the work we do in WordPress is within the system. Write blog posts and publish them is the perfect example of that. As long as the WordPress installation is backed up on a regular basis, that’s fine. But software developers also work on the system. Expanding WordPress with new plugins, installing eCommerce addons, developing a custom theme etc. At some point, those changes needs to be pushed from a developers environment to the production environment, also known as deployment.
If we do that manually using ftp to move files and the WordPress admin area to install plugins by hand, we’re pretty far from an automated workflow, we’d call it manual deployment. But if we can lift ourselves so that deploying a new version of a WordPress site into production is fully automated, well, then we’re working in the spirit of DevOps.
But it’s not enough just to automate and be done. A good deployment process will only deploy code that passes some quality tests. It will allow for some sort of rollback if we discover problems. And it is designed so that we never ever lose data as a result of a deploy. The relevant question is how do we get from a manual deployment workflow to a fully automated safe workflow with quality assurance?
Automation Requires Upfront Work
Let’s just get this out of the way first. There is no silver bullet.
But having said that, there are development tools available that will help you along the way but setting them up correctly will cost you some time at the beginning. Once you’ve spent that time and get it all into place, you’ll gain it back quickly.
Next, we’ll briefly cover the tools that I prefer to work with to create this automated workflow. There are plenty of good tools available, I’d be very happy to hear what tools you have found to solve the same, or other, challenges.
Git for Source Code Control
Git has quickly become the source control and versioning system of choice for many people. The WordPress development team still relies on Subversion but they are also making all of WordPress core as well as all plugins in the official repository available at Github as well.
To maintain code quality we need to use testing and since WordPress is a PHP project, the natural unit testing tool is PHPUnit by Sebastian Bergmann. There are plenty of good tutorials that will help you get started with PHPUnit and WordPress, one of my favorite guides is written by Pippin Williamson.
Vagrant as Development Environment
Vagrant is a piece of software that will help you automate the creation of Virtual Machines right on your development computer. There are many benefits of running your WordPress project inside a Vagrant machine, the most obvious ones are that (1) you can install more or less the same software that you will use in production same version of Apache or nginx, same php version, same mysql version etc. And (2) you can make changes to the development environment without affecting the rest of your computer or any other projects. And (3) it’s super easy to make sure that all developers working on the same project actually has the exact same environment. No more “this works on my machine” conversations.
Grunt and wp-cli for Automation
WP-CFM stands for WordPress configuration management. It’s a tool that helps us store a selection of WordPress settings from the database to a file that we keep in git. WP-CFM was built with wp-cli in mind, so by combining them we get a method of managing WordPress settings in the source code control system so that they are easily moved between development, staging and production. There are a few caveats, but there are luckily some workarounds for those.
Rocketeer for Deployment
There are a few open source deployment systems available. The Ruby system Capistrano might be the most well known right now. For PHP developers there is a system called Rocketeer that does much of the same things but where you can reuse some of your PHP classes (and skills).
So, will WordPress and DevOps get along?
There are some distinct challenges when it comes to automating WordPress web development. In the tools list above I’ve outlined the tools I think we need to create a fully automated deployment process that enables us to move our project from development to other environments.
However, there are a few things that are not covered by any of these tools and it’s the primary reason that WordPress and DevOps sometimes can’t get along at all. It’s the content.
WordPress makes no distinction between content and content. For instance, your particular menu structure is store as a combination of taxonomies and posts. That’s right. A menu item is a type of post. And the start page of your WordPress site is a post. But the blog posts that are written by the site editors are also posts (naturally), and any images that are uploaded on the live site are also posts.
Our challenge is that when we deploy our WordPress site from development to production is that some content (menu and start page for example) are kind of part of the core web site you’ve created and you want the deployment process to transfer (and update) it on the live site. But other content is just content and if the deploy process overwrites normal posts we have a catastrophe on our hands.
WordPress has a hard time seeing the difference and that’s going to be the primary challenge when we want WordPress and DevOps to play along nicely.
The next post will cover how to set up a good development environment using Vagrant and Git and after that we’ll look into automation with Grunt and wp-cli.