Hello,

I've searched for existing issues, apologies if this is a duplicate

We had some troubles using Redlock in a Rails application because of how the server parameter is being detected:

> redis_config = Rails.application.config_for(:redis)
=> {:name=>"master", :url=>"redis://localhost:6379/4", :password=>"pass", :sentinels=>[{:host=>"localhost", :port=>26379, :password=>nil}]}

> Redlock::Client.new([redis_config]).lock!('test', 1000) { 'Ok' }
Redlock::LockError: failed to acquire lock on 'test'

This does not work in Rails by default because redis_config is an ActiveSupport::OrderedOptions object which responds to call, tricking initialize into thinking that it is not a configuration hash.

In fact, by adding to_h, everything is fine

Redlock::Client.new([redis_config.to_h]).lock!('test', 1000) { 'Ok' }
=> "Ok"

I wonder if there could be a different approach, something like:

@redis =
  if connection.is_a?(Hash)
    initialize_client(connection)
  else
    connection
  end

It appears to me that the minimum required Ruby version is 2.5.0 because of the runtime requirement on https://rubygems.org/gems/redis-client/versions/0.14.1

Ruby 2.5.0 defines key? on hash: https://docs.ruby-lang.org/en/2.5.0/Hash.html#method-i-key-3F

I understand that is_a?(Hash) is not the same thing as key?, but in initialize_client, options is being used like a hash with:

• #delete
• #[]
• ** operator

So I guess that this may be a legit change, unless some other options inherit from Hash, which I hope they aren't

I can submit a PR if you are interested