[day-03] add mutation to create user

1. Add input type to receive user details
2. Add resolver to create user
3. Configure mutation in root type
4. Aggregate mutations in schema

lib/wabanex_web/resolvers/user.ex

@@ -2,4 +2,6 @@ defmodule WabanexWeb.Resolvers.User do
   alias Wabanex.Users
 
   def get(%{id: user_id}, _context), do: Users.Get.call(user_id)
+
+  def create(%{input: params}, _context), do: Users.Create.call(params)
 end

lib/wabanex_web/schema.ex

@@ -6,4 +6,8 @@ defmodule WabanexWeb.Schema do
   query do
     import_fields :root_query
   end
+
+  mutation do
+    import_fields :root_mutation
+  end
 end

lib/wabanex_web/schema/types/root.ex

@@ -12,4 +12,12 @@ defmodule WabanexWeb.Schema.Types.Root do
       resolve &UserResolver.get/2
     end
   end
+
+  object :root_mutation do
+    field :create_user, type: :user do
+      arg :input, non_null(:create_user_input)
+
+      resolve &UserResolver.create/2
+    end
+  end
 end

lib/wabanex_web/schema/types/user.ex

@@ -9,4 +9,10 @@ defmodule WabanexWeb.Schema.Types.User do
     field :name, non_null(:string)
     field :email, non_null(:string)
   end
+
+  input_object :create_user_input do
+    field :name, non_null(:string), description: "User name"
+    field :email, non_null(:string), description: "User email"
+    field :password, non_null(:string), description: "User password"
+  end
 end