Module: ReactOnRails::Controller::FormResponders

Defined in:
lib/react_on_rails/controller/form_responders.rb

Overview

Opt-in controller helpers for responding to ‘useRailsForm` submissions (packages/react-on-rails/src/useRailsForm.ts).

The hook posts JSON and expects model validation failures as HTTP 422 with the body shape ‘{ “errors”: { “field_name”: [“message”, …] } }`. This concern renders exactly that shape from any object exposing ActiveModel errors, so a controller action can stay a plain Rails action:

class ContactMessagesController < ApplicationController
  include ReactOnRails::Controller::FormResponders

  def create
    contact_message = ContactMessage.new(contact_message_params)
    if contact_message.save
      render json: { message: "Thanks!" }, status: :created
    else
      render_model_errors(contact_message)
    end
  end
end

Including this concern is optional — ‘useRailsForm` works against any endpoint that returns the documented shape.

Instance Method Summary collapse

Instance Method Details

#render_model_errors(record, status: 422) ⇒ Object

Renders the validation errors of an ActiveModel/ActiveRecord object as JSON in the shape ‘useRailsForm` maps onto per-field errors.

record: any object responding to ‘errors` with `ActiveModel::Errors`

(or anything whose `errors` responds to `messages`).

status: Numeric HTTP status for the response. Defaults to 422

(Unprocessable Content), which is what the hook's error mapping
keys on. Numeric statuses sidestep Rack/Rails status-symbol
renames such as :unprocessable_entity to :unprocessable_content.

SECURITY: ActiveModel error messages are sent to the browser verbatim. Review custom validations for internal IDs, admin-only details, or security-sensitive wording before using this on a model.



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# File 'lib/react_on_rails/controller/form_responders.rb', line 41

def render_model_errors(record, status: 422)
  unless status.is_a?(Integer)
    raise ArgumentError, "render_model_errors status must be an Integer HTTP status code"
  end

  unless record.respond_to?(:errors)
    raise ArgumentError, "render_model_errors record must respond to errors.messages"
  end

  errors = record.errors
  unless errors.respond_to?(:messages)
    raise ArgumentError, "render_model_errors record must respond to errors.messages"
  end

  render json: { errors: errors.messages }, status:
end