Use SimpleForm

.rubocop.yml

@@ -10,9 +10,21 @@ AllCops:
 Layout/AccessModifierIndentation:
   EnforcedStyle: outdent
 
+Layout/AlignHash:
+  EnforcedColonStyle: table
+
 Layout/EmptyLinesAroundArguments:
   Enabled: false
 
+Metrics/BlockLength:
+  Exclude:
+    - 'config/initializers/*.rb'
+
+Metrics/LineLength:
+  Exclude:
+    - 'config/initializers/simple_form.rb'
+    - 'config/initializers/simple_form_bootstrap.rb'
+
 Rails:
   Enabled: true
 

Gemfile

@@ -58,6 +58,10 @@ gem 'bootstrap', '~> 4.1.3'
 # Font-Awesome SASS gem for use in Ruby projects.
 gem 'font-awesome-sass', '~> 5.5.0'
 
+# Forms made easy for Rails!
+# It's tied to a simple DSL, with no opinion on markup.
+gem 'simple_form', '~> 4.1'
+
 group :development, :test do
   # factory_bot provides a framework and DSL for defining and using factories.
   gem 'factory_bot_rails', '~> 4.10'

Gemfile.lock

@@ -190,6 +190,9 @@ GEM
       rake
     shoulda-matchers (4.0.0.rc1)
       activesupport (>= 4.2.0)
+    simple_form (4.1.0)
+      actionpack (>= 5.0)
+      activemodel (>= 5.0)
     simplecov (0.16.1)
       docile (~> 1.1)
       json (>= 1.8, < 3)
@@ -248,6 +251,7 @@ DEPENDENCIES
   rubocop (~> 0.60.0)
   sass-rails (~> 5.0)
   shoulda-matchers (= 4.0.0.rc1)
+  simple_form (~> 4.1)
   simplecov (~> 0.16)
   spring
   spring-watcher-listen (~> 2.0.0)

config/initializers/simple_form.rb

@@ -0,0 +1,179 @@
+# frozen_string_literal: true
+
+# Uncomment this and change the path if necessary to include your own
+# components.
+# See https://github.com/plataformatec/simple_form#custom-components to know
+# more about custom components.
+# Dir[Rails.root.join('lib/components/**/*.rb')].each { |f| require f }
+
+# Use this setup block to configure all options available in SimpleForm.
+SimpleForm.setup do |config|
+  # Wrappers are used by the form builder to generate a
+  # complete input. You can remove any component from the
+  # wrapper, change the order or even add your own to the
+  # stack. The options given below are used to wrap the
+  # whole input.
+  config.wrappers :default, class: :input,
+                            hint_class: :field_with_hint, error_class: :field_with_errors, valid_class: :field_without_errors do |b|
+    ## Extensions enabled by default
+    # Any of these extensions can be disabled for a
+    # given input by passing: `f.input EXTENSION_NAME => false`.
+    # You can make any of these extensions optional by
+    # renaming `b.use` to `b.optional`.
+
+    # Determines whether to use HTML5 (:email, :url, ...)
+    # and required attributes
+    b.use :html5
+
+    # Calculates placeholders automatically from I18n
+    # You can also pass a string as f.input placeholder: "Placeholder"
+    b.use :placeholder
+
+    ## Optional extensions
+    # They are disabled unless you pass `f.input EXTENSION_NAME => true`
+    # to the input. If so, they will retrieve the values from the model
+    # if any exists. If you want to enable any of those
+    # extensions by default, you can change `b.optional` to `b.use`.
+
+    # Calculates maxlength from length validations for string inputs
+    # and/or database column lengths
+    b.optional :maxlength
+
+    # Calculate minlength from length validations for string inputs
+    b.optional :minlength
+
+    # Calculates pattern from format validations for string inputs
+    b.optional :pattern
+
+    # Calculates min and max from length validations for numeric inputs
+    b.optional :min_max
+
+    # Calculates readonly automatically from readonly attributes
+    b.optional :readonly
+
+    ## Inputs
+    # b.use :input, class: 'input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label_input
+    b.use :hint,  wrap_with: { tag: :span, class: :hint }
+    b.use :error, wrap_with: { tag: :span, class: :error }
+
+    ## full_messages_for
+    # If you want to display the full error message for the attribute, you can
+    # use the component :full_error, like:
+    #
+    # b.use :full_error, wrap_with: { tag: :span, class: :error }
+  end
+
+  # The default wrapper to be used by the FormBuilder.
+  config.default_wrapper = :default
+
+  # Define the way to render check boxes / radio buttons with labels.
+  # Defaults to :nested for bootstrap config.
+  #   inline: input + label
+  #   nested: label > input
+  config.boolean_style = :nested
+
+  # Default class for buttons
+  config.button_class = 'btn'
+
+  # Method used to tidy up errors. Specify any Rails Array method.
+  # :first lists the first message for each field.
+  # Use :to_sentence to list all errors for each field.
+  # config.error_method = :first
+
+  # Default tag used for error notification helper.
+  config.error_notification_tag = :div
+
+  # CSS class to add for error notification helper.
+  config.error_notification_class = 'error_notification'
+
+  # Series of attempts to detect a default label method for collection.
+  # config.collection_label_methods = [ :to_label, :name, :title, :to_s ]
+
+  # Series of attempts to detect a default value method for collection.
+  # config.collection_value_methods = [ :id, :to_s ]
+
+  # You can wrap a collection of radio/check boxes in a pre-defined tag, defaulting to none.
+  # config.collection_wrapper_tag = nil
+
+  # You can define the class to use on all collection wrappers. Defaulting to none.
+  # config.collection_wrapper_class = nil
+
+  # You can wrap each item in a collection of radio/check boxes with a tag,
+  # defaulting to :span.
+  # config.item_wrapper_tag = :span
+
+  # You can define a class to use in all item wrappers. Defaulting to none.
+  # config.item_wrapper_class = nil
+
+  # How the label text should be generated altogether with the required text.
+  # config.label_text = lambda { |label, required, explicit_label| "#{required} #{label}" }
+
+  # You can define the class to use on all labels. Default is nil.
+  # config.label_class = nil
+
+  # You can define the default class to be used on forms. Can be overriden
+  # with `html: { :class }`. Defaulting to none.
+  # config.default_form_class = nil
+
+  # You can define which elements should obtain additional classes
+  # config.generate_additional_classes_for = [:wrapper, :label, :input]
+
+  # Whether attributes are required by default (or not). Default is true.
+  # config.required_by_default = true
+
+  # Tell browsers whether to use the native HTML5 validations (novalidate form option).
+  # These validations are enabled in SimpleForm's internal config but disabled by default
+  # in this configuration, which is recommended due to some quirks from different browsers.
+  # To stop SimpleForm from generating the novalidate option, enabling the HTML5 validations,
+  # change this configuration to true.
+  config.browser_validations = false
+
+  # Collection of methods to detect if a file type was given.
+  # config.file_methods = [ :mounted_as, :file?, :public_filename, :attached? ]
+
+  # Custom mappings for input types. This should be a hash containing a regexp
+  # to match as key, and the input type that will be used when the field name
+  # matches the regexp as value.
+  # config.input_mappings = { /count/ => :integer }
+
+  # Custom wrappers for input types. This should be a hash containing an input
+  # type as key and the wrapper that will be used for all inputs with specified type.
+  # config.wrapper_mappings = { string: :prepend }
+
+  # Namespaces where SimpleForm should look for custom input classes that
+  # override default inputs.
+  # config.custom_inputs_namespaces << "CustomInputs"
+
+  # Default priority for time_zone inputs.
+  # config.time_zone_priority = nil
+
+  # Default priority for country inputs.
+  # config.country_priority = nil
+
+  # When false, do not use translations for labels.
+  # config.translate_labels = true
+
+  # Automatically discover new inputs in Rails' autoload path.
+  # config.inputs_discovery = true
+
+  # Cache SimpleForm inputs discovery
+  # config.cache_discovery = !Rails.env.development?
+
+  # Default class for inputs
+  # config.input_class = nil
+
+  # Define the default class of the input wrapper of the boolean input.
+  config.boolean_label_class = 'checkbox'
+
+  # Defines if the default input wrapper class should be included in radio
+  # collection wrappers.
+  # config.include_default_input_wrapper_class = true
+
+  # Defines which i18n scope will be used in Simple Form.
+  # config.i18n_scope = 'simple_form'
+
+  # Defines validation classes to the input_field. By default it's nil.
+  # config.input_field_valid_class = 'is-valid'
+  # config.input_field_error_class = 'is-invalid'
+end

config/initializers/simple_form_bootstrap.rb

@@ -0,0 +1,432 @@
+# frozen_string_literal: true
+
+# Please do not make direct changes to this file!
+# This generator is maintained by the community around simple_form-bootstrap:
+# https://github.com/rafaelfranca/simple_form-bootstrap
+# All future development, tests, and organization should happen there.
+# Background history: https://github.com/plataformatec/simple_form/issues/1561
+
+# Uncomment this and change the path if necessary to include your own
+# components.
+# See https://github.com/plataformatec/simple_form#custom-components
+# to know more about custom components.
+# Dir[Rails.root.join('lib/components/**/*.rb')].each { |f| require f }
+
+# Use this setup block to configure all options available in SimpleForm.
+SimpleForm.setup do |config|
+  # Default class for buttons
+  config.button_class = 'btn'
+
+  # Define the default class of the input wrapper of the boolean input.
+  config.boolean_label_class = 'form-check-label'
+
+  # How the label text should be generated altogether with the required text.
+  config.label_text = ->(label, required, _explicit_label) { "#{label} #{required}" }
+
+  # Define the way to render check boxes / radio buttons with labels.
+  config.boolean_style = :inline
+
+  # You can wrap each item in a collection of radio/check boxes with a tag
+  config.item_wrapper_tag = :div
+
+  # Defines if the default input wrapper class should be included in radio
+  # collection wrappers.
+  config.include_default_input_wrapper_class = false
+
+  # CSS class to add for error notification helper.
+  config.error_notification_class = 'alert alert-danger'
+
+  # Method used to tidy up errors. Specify any Rails Array method.
+  # :first lists the first message for each field.
+  # :to_sentence to list all errors for each field.
+  config.error_method = :to_sentence
+
+  # add validation classes to `input_field`
+  config.input_field_error_class = 'is-invalid'
+  config.input_field_valid_class = 'is-valid'
+
+  # vertical forms
+  #
+  # vertical default_wrapper
+  config.wrappers :vertical_form, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :label, class: 'form-control-label'
+    b.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical input for boolean
+  config.wrappers :vertical_boolean, tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :form_check_wrapper, tag: 'div', class: 'form-check' do |bb|
+      bb.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      bb.use :label, class: 'form-check-label'
+      bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # vertical input for radio buttons and check boxes
+  config.wrappers :vertical_collection, item_wrapper_class: 'form-check', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical input for inline radio buttons and check boxes
+  config.wrappers :vertical_collection_inline, item_wrapper_class: 'form-check form-check-inline', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical file input
+  config.wrappers :vertical_file, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :readonly
+    b.use :label
+    b.use :input, class: 'form-control-file', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical multi select
+  config.wrappers :vertical_multi_select, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'form-control-label'
+    b.wrapper tag: 'div', class: 'd-flex flex-row justify-content-between align-items-center' do |ba|
+      ba.use :input, class: 'form-control mx-1', error_class: 'is-invalid', valid_class: 'is-valid'
+    end
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical range input
+  config.wrappers :vertical_range, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :readonly
+    b.optional :step
+    b.use :label
+    b.use :input, class: 'form-control-range', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # horizontal forms
+  #
+  # horizontal default_wrapper
+  config.wrappers :horizontal_form, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 col-form-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal input for boolean
+  config.wrappers :horizontal_boolean, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper tag: 'label', class: 'col-sm-3' do |ba|
+      ba.use :label_text
+    end
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |wr|
+      wr.wrapper :form_check_wrapper, tag: 'div', class: 'form-check' do |bb|
+        bb.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+        bb.use :label, class: 'form-check-label'
+        bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+        bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+      end
+    end
+  end
+
+  # horizontal input for radio buttons and check boxes
+  config.wrappers :horizontal_collection, item_wrapper_class: 'form-check', tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 form-control-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal input for inline radio buttons and check boxes
+  config.wrappers :horizontal_collection_inline, item_wrapper_class: 'form-check form-check-inline', tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 form-control-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal file input
+  config.wrappers :horizontal_file, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 form-control-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal multi select
+  config.wrappers :horizontal_multi_select, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 control-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.wrapper tag: 'div', class: 'd-flex flex-row justify-content-between align-items-center' do |bb|
+        bb.use :input, class: 'form-control mx-1', error_class: 'is-invalid', valid_class: 'is-valid'
+      end
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal range input
+  config.wrappers :horizontal_range, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :readonly
+    b.optional :step
+    b.use :label, class: 'col-sm-3 form-control-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-control-range', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # inline forms
+  #
+  # inline default_wrapper
+  config.wrappers :inline_form, tag: 'span', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :label, class: 'sr-only'
+
+    b.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.optional :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # inline input for boolean
+  config.wrappers :inline_boolean, tag: 'span', class: 'form-check flex-wrap justify-content-start mr-sm-2', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label, class: 'form-check-label'
+    b.use :error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.optional :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # bootstrap custom forms
+  #
+  # custom input for boolean
+  config.wrappers :custom_boolean, tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :form_check_wrapper, tag: 'div', class: 'custom-control custom-checkbox' do |bb|
+      bb.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      bb.use :label, class: 'custom-control-label'
+      bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  config.wrappers :custom_boolean_switch, tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :form_check_wrapper, tag: 'div', class: 'custom-control custom-checkbox-switch' do |bb|
+      bb.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      bb.use :label, class: 'custom-control-label'
+      bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # custom input for radio buttons and check boxes
+  config.wrappers :custom_collection, item_wrapper_class: 'custom-control', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom input for inline radio buttons and check boxes
+  config.wrappers :custom_collection_inline, item_wrapper_class: 'custom-control custom-control-inline', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom file input
+  config.wrappers :custom_file, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :readonly
+    b.use :label, class: 'form-control-label'
+    b.wrapper :custom_file_wrapper, tag: 'div', class: 'custom-file' do |ba|
+      ba.use :input, class: 'custom-file-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :label, class: 'custom-file-label'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    end
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom multi select
+  config.wrappers :custom_multi_select, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'form-control-label'
+    b.wrapper tag: 'div', class: 'd-flex flex-row justify-content-between align-items-center' do |ba|
+      ba.use :input, class: 'custom-select mx-1', error_class: 'is-invalid', valid_class: 'is-valid'
+    end
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom range input
+  config.wrappers :custom_range, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :readonly
+    b.optional :step
+    b.use :label, class: 'form-control-label'
+    b.use :input, class: 'custom-range', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # Input Group - custom component
+  # see example app and config at https://github.com/rafaelfranca/simple_form-bootstrap
+  # config.wrappers :input_group, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+  #   b.use :html5
+  #   b.use :placeholder
+  #   b.optional :maxlength
+  #   b.optional :minlength
+  #   b.optional :pattern
+  #   b.optional :min_max
+  #   b.optional :readonly
+  #   b.use :label, class: 'form-control-label'
+  #   b.wrapper :input_group_tag, tag: 'div', class: 'input-group' do |ba|
+  #     ba.optional :prepend
+  #     ba.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+  #     ba.optional :append
+  #   end
+  #   b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+  #   b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  # end
+
+  # Floating Labels form
+  #
+  # floating labels default_wrapper
+  config.wrappers :floating_labels_form, tag: 'div', class: 'form-label-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label, class: 'form-control-label'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom multi select
+  config.wrappers :floating_labels_select, tag: 'div', class: 'form-label-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :input, class: 'custom-select custom-select-lg', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label, class: 'form-control-label'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # The default wrapper to be used by the FormBuilder.
+  config.default_wrapper = :vertical_form
+
+  # Custom wrappers for input types. This should be a hash containing an input
+  # type as key and the wrapper that will be used for all inputs with specified type.
+  config.wrapper_mappings = {
+    boolean:       :vertical_boolean,
+    check_boxes:   :vertical_collection,
+    date:          :vertical_multi_select,
+    datetime:      :vertical_multi_select,
+    file:          :vertical_file,
+    radio_buttons: :vertical_collection,
+    range:         :vertical_range,
+    time:          :vertical_multi_select,
+  }
+
+  # enable custom form wrappers
+  # config.wrapper_mappings = {
+  #   boolean:       :custom_boolean,
+  #   check_boxes:   :custom_collection,
+  #   date:          :custom_multi_select,
+  #   datetime:      :custom_multi_select,
+  #   file:          :custom_file,
+  #   radio_buttons: :custom_collection,
+  #   range:         :custom_range,
+  #   time:          :custom_multi_select,
+  # }
+end

config/locales/simple_form.en.yml

@@ -0,0 +1,31 @@
+en:
+  simple_form:
+    "yes": 'Yes'
+    "no": 'No'
+    required:
+      text: 'required'
+      mark: '*'
+      # You can uncomment the line below if you need to overwrite the whole required html.
+      # When using html, text and mark won't be used.
+      # html: '<abbr title="required">*</abbr>'
+    error_notification:
+      default_message: "Please review the problems below:"
+    # Examples
+    # labels:
+    #   defaults:
+    #     password: 'Password'
+    #   user:
+    #     new:
+    #       email: 'E-mail to sign in.'
+    #     edit:
+    #       email: 'E-mail.'
+    # hints:
+    #   defaults:
+    #     username: 'User name to sign in.'
+    #     password: 'No special characters, please.'
+    # include_blanks:
+    #   defaults:
+    #     age: 'Rather not say'
+    # prompts:
+    #   defaults:
+    #     age: 'Select your age'

lib/templates/erb/scaffold/_form.html.erb

@@ -0,0 +1,15 @@
+<%# frozen_string_literal: true %>
+<%%= simple_form_for(@<%= singular_table_name %>) do |f| %>
+  <%%= f.error_notification %>
+  <%%= f.error_notification message: f.object.errors[:base].to_sentence if f.object.errors[:base].present? %>
+
+  <div class="form-inputs">
+  <%- attributes.each do |attribute| -%>
+    <%%= f.<%= attribute.reference? ? :association : :input %> :<%= attribute.name %> %>
+  <%- end -%>
+  </div>
+
+  <div class="form-actions">
+    <%%= f.button :submit %>
+  </div>
+<%% end %>