How to elegantly symbolize_keys for a 'nested' hash

Question

Consider the following code:

  hash1 = {\"one\" => 1, \"two\" => 2, \"three\" => 3}
  hash2 = hash1.reduce({}){ |h, (k,v)| h.merge(k => hash1) }
  ha         


        

Answer 1

You cannot use this method for params or any other instance of ActionController::Parameters any more, because deep_symbolize_keys method is deprecated in Rails 5.0+ due to security reasons and will be removed in Rails 5.1+ as ActionController::Parameters no longer inherits from Hash

So this approach by @Uri Agassi seems to be the universal one.

JSON.parse(JSON[h], symbolize_names: true)

---

However, Rails Hash object still does have it.

So options are:

• if you don't use Rails or just don't care:

  JSON.parse(JSON[h], symbolize_names: true)
  

• with Rails and ActionController::Parameters:

  params.to_unsafe_h.deep_symbolize_keys
  

• with Rails and plain Hash

  h.deep_symbolize_keys