SSL cannot establish secure connection - with Rails 6 app using Devise in Heroku

Question

As the title says, I have a Rails 6 app running in Heroku, with the automatic SSL certificate that Heroku provides. Everything works great, and I can visit any page and it gets the https working fine. However, there is one exception: When users sign up and they get the confirmation email, clicking the link does not work for some reason (see attached screenshots below), and the same happens even if you copy+paste the link in a new tab, of course.

• Ruby version: 2.7.1p83
• Rails version: 6.0.3.1

Firefox:

This is what I get when trying to access that url https://my_domain.com/users/confirmation?confirmation_token=foobar .

My environments/production.rb has these settings:

Rails.application.configure do
  # a few more non important things, and then:
  config.action_mailer.delivery_method = :smtp
  config.action_mailer.perform_deliveries = true
  config.action_mailer.smtp_settings = {
    :user_name => ENV['SENDGRID_USERNAME'],
    :password => ENV['SENDGRID_PASSWORD'],
    :domain => 'my_domain.com',
    :address => 'smtp.sendgrid.net',
    :port => 587,
    :authentication => :plain,
    :enable_starttls_auto => true
  }


  config.force_ssl = true
  config.action_mailer.default_url_options = { :host => 'my_domain.com' }
end

And this is what it looks like in Heroku:

I have these routes for Devise:

Rails.application.routes.draw do
  devise_for :users, controllers: { registrations: 'users/registrations',
                                    confirmations: 'users/confirmations' }
  authenticated :user do
    root to: "depots#index", as: :authenticated_root
  end

  root to: "public/welcome#index"
end

And the controller looks like this:

class Users::ConfirmationsController < Devise::ConfirmationsController
  def after_confirmation_path_for(resource_name, resource)
    sign_in(resource)
    authenticated_root_path
  end
end

Do you guys have any idea on what could be wrong? And if not, any advice on how to troubleshoot this?

UPDATE Aug, 04, 2020:

I had added this redirect to my domain but even though it works redirecting from grownis.com to www.grownis.com it doesn't for https://grownis.com

Answer 1

Your certificate is not wildcard certificate. Please check this link.

https://grownis.com/

The confirmation link is https://grownis.com/users/confirmation?confirmation_token=CONRIMATION_TOKEN

You will need to make a redirection from non-www to www or purchase wildcard certificate.