module ChefSpec::Cacher
The cacher module allows for ultra-fast tests by caching the results of a CCR in memory across an example group. In testing, this can reduce the total testing time by a factor of 10x. This strategy is not the default behavior, because it has implications surrounding stubbing and is not threadsafe!
The credit for this approach and code belongs to Juri Timošin (DracoAter). Please see his original blog post below for an in-depth explanation of how and why this approach is faster.
@example Using the Cacher
module
First, require the Cacher module in your +spec_helper.rb+: RSpec.configure do |config| config.extend(ChefSpec::Cacher) end Next, change your +let+ blocks to +cached+ blocks: let(:chef_run) { ... } #=> cached(:chef_run) { ... } Finally, celebrate!
@warn
This strategy is only recommended for advanced users, as it makes stubbing slightly more difficult and indirect!
@see dracoater.blogspot.com/2013/12/testing-chef-cookbooks-part-25-speeding.html
Constants
- FINALIZER
Public Instance Methods
cached(name, &block)
click to toggle source
# File lib/chefspec/cacher.rb, line 36 def cached(name, &block) location = ancestors.first.metadata[:location] unless location.nil? location += ancestors.first.metadata[:description] unless ancestors.first.metadata[:description].nil? location += ancestors.first.metadata[:scoped_id] unless ancestors.first.metadata[:scoped_id].nil? end location ||= ancestors.first.metadata[:parent_example_group][:location] define_method(name) do key = [location, name.to_s].join(".") unless @@cache.key?(Thread.current.object_id) ObjectSpace.define_finalizer(Thread.current, FINALIZER) end @@cache[Thread.current.object_id] ||= {} @@cache[Thread.current.object_id][key] ||= instance_eval(&block) end end
cached!(name, &block)
click to toggle source
# File lib/chefspec/cacher.rb, line 54 def cached!(name, &block) cached(name, &block) before { send(name) } end