Programming Phoenix

Adding Categories

In this section, we’re going to add some categories. We’ll use many of the same techniques we discovered in our user-to-video relationship to manage the relationships between videos and categories. A video optionally belongs to a category, one chosen by the end user. First, let’s generate the model and migration, using phoenix.gen.model, like this:

$ mix phoenix.gen.model Category categories name:string

* creating priv/repo/migrations/20150829145417_create_category.exs
* creating web/models/category.ex
* creating test/models/category_test.exs

This generator will build the model with a schema and migration for us.

Generating Category Migrations

Next let’s edit our migration to mark the name field as ...