Craft GraphQL APIs in Elixir with Absinthe

Our First Module

In Chapter 5, ​Making a Change with Mutations​, we added several resolution functions that all copied an error-handling function we first developed to power the :create_menu_item mutation field. This error-handling function enabled the system to give users feedback about errors that bubble up from the underlying database—from internal schema-validation problems like missing and badly formatted arguments to database constraint violations.

Let’s take a look at that resolver again:

07-chp.middleware/1-start/lib/plate_slate_web/resolvers/menu.ex

​def​ create_item(_, %{​input:​ params}, _) ​do​
  ​case​ Menu.create_item(params) ​do​
    {​:error​, changeset} ->
      {​:ok​, %{​errors: ...