Merge branch 'defunkt' into distributed

Conflicts:
	lib/resque/worker.rb

Gemfile

@@ -7,4 +7,6 @@ group :test do
   gem "rack-test", "~> 0.5"
   gem "mocha", "~> 0.9.7"
   gem "leftright", :platforms => :mri_18
+  gem "yajl-ruby", "~>0.8.2", :platforms => :mri
+  gem "json", "~>1.5.3", :platforms => :jruby
 end

README.markdown

@@ -560,13 +560,8 @@ together. But, it's not that hard.
 Resque Dependencies
 -------------------
 
-    gem install redis redis-namespace yajl-ruby vegas sinatra
-
-If you cannot install `yajl-ruby` (JRuby?), you can install the `json`
-gem and Resque will use it instead.
-
-When problems arise, make sure you have the newest versions of the
-`redis` and `redis-namespace` gems.
+    $ gem install bundler
+    $ bundle install
 
 
 Installing Resque
@@ -606,7 +601,7 @@ Alternately you can define a `resque:setup` hook in your Rakefile if you
 don't want to load your app every time rake runs.
 
 
-### In a Rails app, as a gem
+### In a Rails 2.x app, as a gem
 
 First install the gem.
 
@@ -637,7 +632,7 @@ Don't forget you can define a `resque:setup` hook in
 `lib/tasks/whatever.rake` that loads the `environment` task every time.
 
 
-### In a Rails app, as a plugin
+### In a Rails 2.x app, as a plugin
 
     $ ./script/plugin install git://github.com/defunkt/resque
 
@@ -652,6 +647,40 @@ Don't forget you can define a `resque:setup` hook in
 `lib/tasks/whatever.rake` that loads the `environment` task every time.
 
 
+### In a Rails 3 app, as a gem
+
+First include it in your Gemfile.
+
+    $ cat Gemfile
+    ...
+    gem 'resque'
+    ...
+
+Next install it with Bundler.
+
+    $ bundle install
+
+Now start your application:
+
+    $ rails server
+
+That's it! You can now create Resque jobs from within your app.
+
+To start a worker, add this to a file in `lib/tasks` (ex:
+`lib/tasks/resque.rake`):
+
+``` ruby
+require 'resque/tasks'
+```
+
+Now:
+
+    $ QUEUE=* rake environment resque:work
+
+Don't forget you can define a `resque:setup` hook in
+`lib/tasks/whatever.rake` that loads the `environment` task every time.
+
+
 Configuration
 -------------
 

docs/HOOKS.md

@@ -66,6 +66,9 @@ An unnamed hook (`before_perform`) will be executed first.
 
 The available hooks are:
 
+* `before _enqueue`: Called with the job args before a job is placed on the queue.
+  If the hook returns `false`, the job will not be placed on the queue.
+
 * `after_enqueue`: Called with the job args after a job is placed on the queue.
   Any exception raised propagates up to the code which queued the job.
 

examples/god/resque.god

@@ -4,6 +4,7 @@ num_workers = rails_env == 'production' ? 5 : 2
 
 num_workers.times do |num|
   God.watch do |w|
+    w.dir      = "#{rails_root}"
     w.name     = "resque-#{num}"
     w.group    = 'resque'
     w.interval = 30.seconds

lib/resque.rb

@@ -1,11 +1,5 @@
 require 'redis/namespace'
 
-begin
-  require 'yajl'
-rescue LoadError
-  require 'json'
-end
-
 require 'resque/version'
 
 require 'resque/errors'
@@ -230,6 +224,12 @@ def watch_queue(queue)
   #
   # This method is considered part of the `stable` API.
   def enqueue(klass, *args)
+    # Perform before_enqueue hooks. Don't perform enqueue if any hook returns false
+    before_hooks = Plugin.before_enqueue_hooks(klass).collect do |hook|
+      klass.send(hook, *args)
+    end
+    return if before_hooks.any? { |result| result == false }
+
     Job.create(queue_from_class(klass), klass, *args)
 
     Plugin.after_enqueue_hooks(klass).each do |hook|

lib/resque/failure/redis.rb

@@ -9,7 +9,7 @@ def save
           :payload   => payload,
           :exception => exception.class.to_s,
           :error     => exception.to_s,
-          :backtrace => Array(exception.backtrace),
+          :backtrace => filter_backtrace(Array(exception.backtrace)),
           :worker    => worker.to_s,
           :queue     => queue
         }
@@ -41,6 +41,11 @@ def self.remove(index)
         Resque.redis.lset(:failed, index, id)
         Resque.redis.lrem(:failed, 1, id)
       end
+
+      def filter_backtrace(backtrace)
+        index = backtrace.index { |item| item.include?('/lib/resque/job.rb') }
+        backtrace.first(index.to_i)
+      end
     end
   end
 end

lib/resque/helpers.rb

@@ -1,3 +1,11 @@
+require 'multi_json'
+
+# OkJson won't work because it doesn't serialize symbols
+# in the same way yajl and json do.
+if MultiJson.engine.to_s == 'MultiJson::Engines::OkJson'
+  raise "Please install the yajl-ruby or json gem"
+end
+
 module Resque
   # Methods used by various classes in Resque.
   module Helpers
@@ -11,29 +19,17 @@ def redis
     # Given a Ruby object, returns a string suitable for storage in a
     # queue.
     def encode(object)
-      if defined? Yajl
-        Yajl::Encoder.encode(object)
-      else
-        object.to_json
-      end
+      ::MultiJson.encode(object)
     end
 
     # Given a string, returns a Ruby object.
     def decode(object)
       return unless object
 
-      if defined? Yajl
-        begin
-          Yajl::Parser.parse(object, :check_utf8 => false)
-        rescue Yajl::ParseError => e
-          raise DecodeException, e
-        end
-      else
-        begin
-          JSON.parse(object)
-        rescue JSON::ParserError => e
-          raise DecodeException, e
-        end
+      begin
+        ::MultiJson.decode(object)
+      rescue ::MultiJson::DecodeError => e
+        raise DecodeException, e
       end
     end
 

lib/resque/plugin.rb

@@ -47,5 +47,10 @@ def failure_hooks(job)
     def after_enqueue_hooks(job)
       job.methods.grep(/^after_enqueue/).sort
     end
+
+    # Given an object, returns a list `before_enqueue` hook names.
+    def before_enqueue_hooks(job)
+      job.methods.grep(/^before_enqueue/).sort
+    end
   end
 end

lib/resque/worker.rb

@@ -37,13 +37,13 @@ def self.working
 
       reportedly_working = begin
         redis.mapped_mget(*names).reject do |key, value|
-          value.nil?
+          value.nil? || value.empty?
         end
       rescue Redis::Distributed::CannotDistribute
         result = {}
         names.each do |name|
           value = redis.get name
-          result[name] = value unless value.nil?
+          result[name] = value unless value.nil? || value.empty?
         end
         result
       end

resque.gemspec

@@ -24,7 +24,7 @@ Gem::Specification.new do |s|
   s.add_dependency "redis-namespace", "~> 1.0.2"
   s.add_dependency "vegas",           "~> 0.1.2"
   s.add_dependency "sinatra",         ">= 0.9.2"
-  s.add_dependency "json",            ">= 1.4.6", "< 1.6"
+  s.add_dependency "multi_json",      "~> 1.0"
 
   s.description = <<description
     Resque is a Redis-backed Ruby library for creating background jobs,

test/job_hooks_test.rb

@@ -250,6 +250,46 @@ def self.perform(history)
   end
 end
 
+
+context "Resque::Job before_enqueue" do
+  include PerformJob
+
+  class ::BeforeEnqueueJob
+    @queue = :jobs
+    def self.before_enqueue_record_history(history)
+      history << :before_enqueue
+    end
+
+    def self.perform(history)
+    end
+  end
+
+  class ::BeforeEnqueueJobAbort
+    @queue = :jobs
+    def self.before_enqueue_abort(history)
+      false
+    end
+
+    def self.perform(history)
+    end
+  end
+
+  test "the before enqueue hook should run" do
+    history = []
+    @worker = Resque::Worker.new(:jobs)
+    Resque.enqueue(BeforeEnqueueJob, history)
+    @worker.work(0)
+    assert_equal history, [:before_enqueue], "before_enqueue was not run"
+  end
+
+  test "a before enqueue hook that returns false should prevent the job from getting queued" do
+    history = []
+    @worker = Resque::Worker.new(:jobs)
+    Resque.enqueue(BeforeEnqueueJobAbort, history)
+    assert_equal 0, Resque.size(:jobs)
+  end
+end
+
 context "Resque::Job all hooks" do
   include PerformJob