Lazy-load adapters, fixes #6

3 files changed, 32 insertions, 5 deletions

diff --git a/lib/active_job/base.rb b/lib/active_job/base.rb
index 6cce770466..f39dba6f5f 100644
--- a/lib/active_job/base.rb
+++ b/lib/active_job/base.rb
@@ -1,9 +1,9 @@
+require 'active_job/errors'
 require 'active_job/queue_adapters/inline_adapter'
-require 'active_job/queue_adapters/resque_adapter'
-require 'active_job/queue_adapters/sidekiq_adapter'
-require 'active_job/queue_adapters/sucker_punch_adapter'
+require 'active_support/core_ext/string/inflections'
 
 module ActiveJob
+
   class Base
     cattr_accessor(:queue_adapter)   { ActiveJob::QueueAdapters::InlineAdapter }
     cattr_accessor(:queue_base_name) { "active_jobs" }
@@ -13,10 +13,25 @@ module ActiveJob
       def enqueue(*args)
         queue_adapter.queue self, *args
       end
-      
+
       def queue_as(part_name)
         self.queue_name = "#{queue_base_name}_#{part_name}"
       end
+
+      def adapter=(adapter_name)
+        adapter_name = adapter_name.to_s
+        unless %w(inline resque sidekiq sucker_punch).include?(adapter_name)
+          fail ActiveJob::NotImplementedError
+        end
+
+        begin
+          require_relative "queue_adapters/#{adapter_name}_adapter"
+          ActiveJob::Base.queue_adapter = "ActiveJob::QueueAdapters::#{adapter_name.camelize}Adapter".constantize
+        rescue
+          fail ActiveJob::Error.new("#{adapter_name} is missing")
+        end
+      end
     end
+
   end
 end
\ No newline at end of file
diff --git a/lib/active_job/errors.rb b/lib/active_job/errors.rb
new file mode 100644
index 0000000000..4fc3be6878
--- /dev/null
+++ b/lib/active_job/errors.rb
@@ -0,0 +1,12 @@
+module ActiveJob
+
+  class NotImplementedError < ::NotImplementedError #:nodoc:
+  end
+
+  class Error < ::StandardError #:nodoc:
+    def initialize(message = nil)
+      super(message)
+    end
+  end
+
+end
\ No newline at end of file
diff --git a/lib/active_job/job_wrappers/resque_wrapper.rb b/lib/active_job/job_wrappers/resque_wrapper.rb
index 0db9cf144f..cbeee4fb1b 100644
--- a/lib/active_job/job_wrappers/resque_wrapper.rb
+++ b/lib/active_job/job_wrappers/resque_wrapper.rb
@@ -2,7 +2,7 @@ require 'resque'
 
 require 'active_support/core_ext/enumerable'
 require 'active_support/core_ext/array/access'
-require 'active_support/core_ext/string/inflections'
+
 
 
 module ActiveJob