small ecto changeset example

changeset.ex

def new_changeset(model, params \\ %{}) do
  model
  |> cast(params, ~w(name username))
  |> validate_required(~w(name username))
  |> unique_constraint(:username)
  |> validate_length(:username, min: 1, max: 20)
end

def registration_changeset(model, params) do
  model
  |> new_changeset(params)
  |> cast(params, ~w(password))
  |> validate_required(~w(password))
  |> validate_length(:password, min: 6, max: 100)
  |> put_pass_hash()
end