Inputs with dry-validation v2

controller.rb

def new
  # initialize a hash from 
  @inputs = Form.new( 
    user_name: '',
    some_field: some_object.default_some_field,
    something: {
      a: '',
      b: 'some default value'
    }
  )
end
 
def create
  create_user = CreateUserTransaction.new
  
  create_user.call(params) do |result|
  result.success do |outcome|
    #..
    redirect...
  end

  result.failure do |outcome|
    flash.now[:error] = outcome[:description]
    @inputs = Form.new(outcome[:validation])
    render :edit
  end
end

form.rb

class Form
  def initialize(inputs)
    @inputs = inputs
  end
  
  def value(*keys)
    inputs.dig(*keys)
  end
  
  def error(*keys)
    errors.dig(*keys).first
  end
  
  def errors
    @errors ||= build_errors
  end
  
  private
  
  attr_reader :inputs
  
  def build_errors
    return {} unless inputs.respond_to?(:errors)
    
    inputs.errors.to_h
  end
end

view.rb

<input name="user_name" type="text" value="<%= inputs.value(:user_name) %>" />
<% if form.error(:user_name) %>
<span class="text-danger"><%= form.error(:user_name) %></span>
<% end %>

<h3>Something</h3>
<input name="user_name[something][a]" type="text" value="<%= inputs.value(:something, :a) %>" />
<% if form.error(:something, :a) %>
<span class="text-danger"><%= form.error(:somethind, :a) %></span>
<% end %>