Craft GraphQL APIs in Elixir with Absinthe

Building the Resolver

Let’s build the resolver function. It will grab the :input argument for us, and then call a general-purpose PlateSlate.Menu.create_item/1 function that will handle attempting to persist the record:

05-chp.mutations/2-create/lib/plate_slate_web/resolvers/menu.ex

​def​ create_item(_, %{​input:​ params}, _) ​do​
  ​case​ Menu.create_item(params) ​do​ 
    {​:error​, _} ->
      {​:error​, ​"​​Could not create menu item"​}
    {​:ok​, _} = success ->
      success
  ​end​
​end​

Here’s how we’ve implemented PlateSlate.Menu.create_item/1:

05-chp.mutations/2-create/lib/plate_slate/menu/menu.ex

​def​ create_item(attrs \\ %{}) ​do​