Flop 0.29.0 released!

Flop 0.29.0 has been released.

Added

• Add Flop.allowed_fields/2, which returns the fields that may be filtered or
  sorted for the given options.
• Add Flop.Schema.flop_schema!/1, which returns the configuration of a schema
  module.
• Add Flop.Cursor.get_cursor_from_node/3 and
  Flop.Cursor.get_cursor_from_edge/3, which take the query options and resolve
  a field against the schema given as :for.
• Accept an arity-3 cursor_value_func, which also receives the options the
  query ran with.

Changed

• Turn Flop.Schema from a protocol into a behaviour. Schemas are configured
  with use Flop.Schema and the @flop_options attribute now.
• Take the schema module instead of a struct in Flop.Schema.field_info/2,
  Flop.Schema.get_field/3 and Flop.Schema.primary_key/1.
• Default cursor_value_func to Flop.Cursor.get_cursor_from_node/3.

Removed

• Remove default_limit/1, default_order/1, default_pagination_type/1,
  filterable/1, max_filters/1, max_limit/1, pagination_types/1,
  sortable/1 and tiebreaker/1 from Flop.Schema.

Fixed

• Do not make a module named in an ecto_type a compile-time dependency of the
  schema.
• Read a cursor value through the schema given as :for, so that a field’s
  :path is applied when the query returns plain maps rather than structs.

How to upgrade

Change your code to use Flop.Schema and set the options as @flop_options
instead of using @derive to derive the protocol.

 defmodule MyApp.Pet do
   use Ecto.Schema
+  use Flop.Schema

-  @derive {
-    Flop.Schema,
-    filterable: [:name, :species],
-    sortable: [:name, :age]
-  }
+  @flop_options [
+    filterable: [:name, :species],
+    sortable: [:name, :age]
+  ]

   schema "pets" do
     field :name, :string
     field :age, :integer
     field :species, :string
   end
 end

The attribute is read when the module finishes compiling, so it can go anywhere
in the module body. If you use an alias in the options, the alias has to be
declared before the module attribute.

The functions that returned a single schema option are gone. Read the effective
value through Flop.get_option/3, which also applies the backend module and the
application environment, or Flop.allowed_fields/2 for filterable and
sortable, which applies the narrowing a query function may have set:

-Flop.Schema.sortable(%MyApp.Pet{})
+Flop.allowed_fields(:sortable, for: MyApp.Pet)

-Flop.Schema.max_limit(%MyApp.Pet{})
+Flop.get_option(:max_limit, for: MyApp.Pet)

The remaining functions take the schema module instead of a struct:

-Flop.Schema.field_info(%MyApp.Pet{}, :name)
+Flop.Schema.field_info(MyApp.Pet, :name)

-Flop.Schema.get_field(pet, :owner_name)
+Flop.Schema.get_field(MyApp.Pet, pet, :owner_name)

An arity-2 cursor_value_func is still supported. You can use a 3-arity
function if you need the schema or other options passed to Flop, for example if
you need to apply the path option of join or custom fields.

-cursor_value_func: fn item, fields -> Map.take(item, fields) end
+cursor_value_func: fn item, fields, opts ->
+  Map.new(fields, &{&1, Flop.Schema.get_field(opts[:for], item, &1)})
+end