Param is missing or the value is empty: within new - ruby-on-rails

Question

I'm running into this issue working with a form in rails, and was wondering if anybody could take a quick look with it.
My view looks like
= form_for #form_submission do |f|
- if #form_submission.errors.any?
#error_explanation
%h2= "#{pluralize(#form_submission.errors.count, "error")} prohibited this form_submission from being saved:"
%ul
- #form_submission.errors.full_messages.each do |msg|
%li= msg
..and my controller is like so
class FormSubmissionsController < ApplicationController
invisible_captcha only: [:create], on_spam: :handle_spam
def new
#form_submission = FormSubmission.new(form_submission_params)
if #form_submission.save
redirect_to thank_you_path
else
redirect_to root_path
end
end
private
def handle_spam
redirect_to root_path
end
def form_submission_params
params.require(:form_submission).permit(:first_name, :last_name, :organization, :email, :phone)
end
end
Ultimately my problem is that I don't know what params i'm missing. Or even if my value is empty, how would I know, and what could I do to resolve that?

Answer 1

Standard rails approach to forms is your new action is a 'GET' and is used to show the new view for the creation of a resource. The form 'POST's to the create action with the form fields added to the params hash. Your controller methods should be
def new
#form_submission = FormSubmission.new
end
def create
#form_submission = FormSubmission.new(form_submission_params)
if #form_submission.save
redirect_to thank_you_path
else
redirect_to root_path
end
end
Check your routes by running rake routes in the terminal and make sure you have a routes to that point to form_submissions#new and form_submissions#create.
When you click on the submit button you will be able to view the parameters that are being passed in the logs and it should look something like
Parameters: {"utf8"=>"✓", "authenticity_token"=>"someRandomStuff", "form_submission"=>{"first_name"=>"value entered in first_name field", "last_name"=>"value entered in last_name field"}, "commit"=>"Value of submit button"}
Are you really creating a resource called FormSubmission?

Answer 2

I think you're doing it the wrong way.
this is what you should do :
def new
#form_submission = FormSubmission.new
end
def create
#form_submission = FormSubmission.new(form_submission_params)
if #form_submission.save
redirect_to thank_you_path
else
redirect_to root_path
end
end
As said in comments,
"new" action is used to initialize your ressource as empty or with default value.
"create" action is used to save your new ressource