Day 05 - Account Subscriptions [Rails 5]


  • Application: Complete and tested with one endpoint
  • CI: Complete
  • Deployment:
    • Dev: Complete
    • Production: Complete


Week two started off with a trip back to Rails 5. Carson Stauffer was able to pair with me for an account subscription api. We started off with API design which was really insightful since the previous model locked our subscriptions to only an email. Carson had a great idea to increase flexibilty of contact channels by altering the table structure to handle dynamic channels such as SMS or messengers. After a week of iterations, the process became pretty smooth and looked like this:

Design: * Interface * methods * inputs * schema * Naming (not as easy as it sounds)

Skeleton: * Github repository * Docker hub repository * Choose service port * Generate application using our CLI

Configure: * DataDog * dotenv * database * honeybadger * health check endpoint

Implement: * generate endpoints * write more tests * add pagination * json schema for 1.0

Deployment: * circle CI * Docker * Dockerfile * rancher configuration

Now that we've done this a few times, maybe we should flip the deployment and implement since thats our goal. As an engineering organization we could work more efficiently if the application is deployed with minimum effort and we begin iterating immediately.

Learning for the day: API Generators

Naming APIs
There are only two hard things in Computer Science: cache invalidation and naming things.

-- Phil Karlton

Naming is one of the two hard things to do in Computer Science. Today we started with something as simple as email subscriptions but since we generalized it, email didn't make sense. There were magnetic poetry words on a whiteboard behind us so I immediately went to suggest fun word combinations. Those included dragon-byte, virus-love information-dungeon, and even some that were somewhat close to topic such as byte-marketing. Ultimately Carson made a great case that although those names all sounds like fun, they hide the purpose of the service. So we settle on account subscription.

Namespaced Generators

We leverage rails scaffolding to generate endpoints quickly, but they always seem to need work to get them perfect. In particular, we need proper namespacing for versioning in the future. Although not an extreme amount of work to hand build, we saved a lot of time by namespacing when generating the scaffolding.

In rails you can add namespaces to your objects and it will automatically add those namespaces to your files.

$ rails g scaffold AccountSubscriptons::V1::Subscriptions name:string
  invoke  active_record
  create    db/migrate/20170613064344_create_account_subscription_v1_subscriptions.rb
  create    app/models/account_subscription/v1/subscription.rb
  create    app/models/account_subscription/v1.rb
  invoke    test_unit
  create      test/models/account_subscription/v1/subscription_test.rb
  create      test/fixtures/account_subscription/v1/subscriptions.yml
  invoke  resource_route
   route    namespace :account_subscription do
                namespace :v1 do
                  resources :subscriptions
  invoke  scaffold_controller
  create    app/controllers/account_subscription/v1/subscriptions_controller.rb
  invoke    test_unit
  create      test/controllers/account_subscription/v1/subscriptions_controller_test.rb
  invoke    jbuilder
  create      app/views/account_subscription/v1/subscriptions
  create      app/views/account_subscription/v1/subscriptions/index.json.jbuilder
  create      app/views/account_subscription/v1/subscriptions/show.json.jbuilder
  create      app/views/account_subscription/v1/subscriptions/_account_subscription_v1_subscription.json.jbuilder

This is nice but not ideal. It has segmented off the models into a namespace as well, when all we needed was the controller to be namespace.

More customized generators will be a perfect addition to our CLI.