discourse/lib/distributed_cache.rb

# frozen_string_literal: true

require 'message_bus/distributed_cache'

class DistributedCache < MessageBus::DistributedCache
  def initialize(key, manager: nil, namespace: true)
    super(
      key,
      manager: manager,
      namespace: namespace,
      app_version: Discourse.git_version
    )
  end

  # Defer setting of the key in the cache for performance critical path to avoid
  # waiting on MessageBus to publish the message which involves writing to Redis.
  def defer_set(k, v)
    Scheduler::Defer.later("#{@key}_set") do
      self[k] = v
    end
  end

  def defer_get_set(k, &block)
    return self[k] if self[k]
    value = block.call
    self.defer_set(k, value)
    value
  end
end