Code Reading - Capistrano

A fascinating glimpse into Spencer’s server config process.

Impetus:

Contractor working on our marketing website CMS needs a staging environment to deploy changes to.

Context:

We set up a one-click droplet on Digital Ocean. But we use chef for server management, so we need to custom configure this setup.

Requirements:

  • Wordpress
  • MySQL
  • Varnish (service that sits in front of web applications like Wordpress, handles caching, kinda like nginx with caching)

What we did:

First step was looking at our existing chef cookbooks and seeing if there’s anything we can reuse. Turns out we have fis-msql cookbook already - but why? We don’t use MySQL on production. So look for a corresponding droplet on Digital Ocean; can’t find one.

Git blamed cookbook, and it was added in March around the same time this marketing site CMS project was originally kicked off (later put on paused, restarted now).

Side note: Spencer is using the Elflord color scheme for VIM. Loves it.

Diving into fis-msql cookbook code:

  • see our base cookbook
  • setting up msql v5.6, so update to latest v5.7 (bc why not)
  • rm mysql2_chef_gem (don’t need it)
  • rm chef-cookbooks/database bc it was doomed and deprecated
  • rm all code associated with deprecated database cookbook

Lots of unknowns:

  • Seeing attributes for db_names
  • Seeing references to Scotch Box, a Vagrant LAMP stack.
  • Where did flatiron-v3-db.sql come from? is it worth keeping?

Next tried setting up regular ol’ Vagrant (the best supported utility machine for Mac, de facto standard). Then learned that better to use vagrant-berkshelf thing. Then saw that maintainers actually favored using test-kitchen.

Side note: we tried getting Vagrant running with Ironbroker, RabbitMQ, etc., but turned out to be waaaay too big a project for us. Abandoned.

Benefits of test-kitchen:

  • can run script locally to see how it builds
  • sets up virtual machine
  • ops code supported; good documentation

Ran into a problem: SSH keys are awkward because of the way our fis-users cookbook is set up. We kinda block root user, and default Vagrant user isn’t in default admin list. Workaround: test-kitchen spins up an ssh key pair on the fly and uses that instead.

Now can run kitchen login to ssh onto box as vagrant user. BUT how do we ssh in as a different user? Set username in .kitchen/default-ubuntu-1604.yml (instance specific config).

Once we’re on the box, turns out you can’t sudo mysql... because mysql has its own permissions layer.

Next steps:

  1. Adding Varnish
  2. Getting that sudo permissions stuff working
  3. Once we’ve got this all working, maybe add a QA environment too?
Written on April 20, 2017