[ruby-on-rails] Rails: Can't verify CSRF token authenticity when making a POST request

There is relevant info on a configuration of CSRF with respect to API controllers on api.rubyonrails.org:

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It's important to remember that XML or JSON requests are also affected and if you're building an API you should change forgery protection method in ApplicationController (by default: :exception):

class ApplicationController < ActionController::Base
  protect_from_forgery unless: -> { request.format.json? }
end

We may want to disable CSRF protection for APIs since they are typically designed to be state-less. That is, the request API client will handle the session for you instead of Rails.

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