10 files changed, 103 insertions, 1 deletions
diff --git a/activejob/CHANGELOG.md b/activejob/CHANGELOG.md
index 097433c3d0..c6a3ad8ade 100644
--- a/activejob/CHANGELOG.md
+++ b/activejob/CHANGELOG.md
@@ -1,5 +1,13 @@
 ## Rails 6.0.0.alpha (Unreleased) ##
 
+*   Add support for timezones to Active Job
+
+    Record what was the current timezone in effect when the job was
+    enqueued and then restore when the job is executed in same way
+    that the current locale is recorded and restored.
+
+    *Andrew White*
+
 *   Rails 6 requires Ruby 2.4.1 or newer.
 
     *Jeremy Daer*
diff --git a/activejob/lib/active_job/base.rb b/activejob/lib/active_job/base.rb
index 6194f89956..2b2a59e969 100644
--- a/activejob/lib/active_job/base.rb
+++ b/activejob/lib/active_job/base.rb
@@ -9,6 +9,7 @@ require "active_job/execution"
 require "active_job/callbacks"
 require "active_job/exceptions"
 require "active_job/logging"
+require "active_job/timezones"
 require "active_job/translation"
 
 module ActiveJob #:nodoc:
@@ -68,6 +69,7 @@ module ActiveJob #:nodoc:
     include Callbacks
     include Exceptions
     include Logging
+    include Timezones
     include Translation
 
     ActiveSupport.run_load_hooks(:active_job, self)
diff --git a/activejob/lib/active_job/core.rb b/activejob/lib/active_job/core.rb
index 879746fc01..da841ae45b 100644
--- a/activejob/lib/active_job/core.rb
+++ b/activejob/lib/active_job/core.rb
@@ -31,6 +31,9 @@ module ActiveJob
 
       # I18n.locale to be used during the job.
       attr_accessor :locale
+
+      # Timezone to be used during the job.
+      attr_accessor :timezone
     end
 
     # These methods will be included into any Active Job object, adding
@@ -87,7 +90,8 @@ module ActiveJob
         "priority"   => priority,
         "arguments"  => serialize_arguments(arguments),
         "executions" => executions,
-        "locale"     => I18n.locale.to_s
+        "locale"     => I18n.locale.to_s,
+        "timezone"   => Time.zone.try(:name)
       }
     end
 
@@ -125,6 +129,7 @@ module ActiveJob
       self.serialized_arguments = job_data["arguments"]
       self.executions           = job_data["executions"]
       self.locale               = job_data["locale"] || I18n.locale.to_s
+      self.timezone             = job_data["timezone"] || Time.zone.try(:name)
     end
 
     private
diff --git a/activejob/lib/active_job/timezones.rb b/activejob/lib/active_job/timezones.rb
new file mode 100644
index 0000000000..83f459aea5
--- /dev/null
+++ b/activejob/lib/active_job/timezones.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module ActiveJob
+  module Timezones #:nodoc:
+    extend ActiveSupport::Concern
+
+    included do
+      around_perform do |job, block, _|
+        Time.use_zone(job.timezone, &block)
+      end
+    end
+  end
+end
diff --git a/activejob/test/cases/job_serialization_test.rb b/activejob/test/cases/job_serialization_test.rb
index 440051c427..5c9994508e 100644
--- a/activejob/test/cases/job_serialization_test.rb
+++ b/activejob/test/cases/job_serialization_test.rb
@@ -54,4 +54,11 @@ class JobSerializationTest < ActiveSupport::TestCase
     job.provider_job_id = "some value set by adapter"
     assert_equal job.provider_job_id, job.serialize["provider_job_id"]
   end
+
+  test "serialize stores the current timezone" do
+    Time.use_zone "Hawaii" do
+      job = HelloJob.new
+      assert_equal "Hawaii", job.serialize["timezone"]
+    end
+  end
 end
diff --git a/activejob/test/cases/timezones_test.rb b/activejob/test/cases/timezones_test.rb
new file mode 100644
index 0000000000..e2095b020d
--- /dev/null
+++ b/activejob/test/cases/timezones_test.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+require "helper"
+require "jobs/timezone_dependent_job"
+
+class TimezonesTest < ActiveSupport::TestCase
+  setup do
+    JobBuffer.clear
+  end
+
+  test "it performs the job in the given timezone" do
+    job = TimezoneDependentJob.new("2018-01-01T00:00:00Z")
+    job.timezone = "London"
+    job.perform_now
+
+    assert_equal "Happy New Year!", JobBuffer.last_value
+
+    job = TimezoneDependentJob.new("2018-01-01T00:00:00Z")
+    job.timezone = "Eastern Time (US & Canada)"
+    job.perform_now
+
+    assert_equal "Just 5 hours to go", JobBuffer.last_value
+  end
+end
diff --git a/activejob/test/integration/queuing_test.rb b/activejob/test/integration/queuing_test.rb
index 32ef485c45..7a95d3d039 100644
--- a/activejob/test/integration/queuing_test.rb
+++ b/activejob/test/integration/queuing_test.rb
@@ -110,6 +110,22 @@ class QueuingTest < ActiveSupport::TestCase
     end
   end
 
+  test "current timezone is kept while running perform_later" do
+    skip if adapter_is?(:inline)
+
+    begin
+      current_zone = Time.zone
+      Time.zone = "Hawaii"
+
+      TestJob.perform_later @id
+      wait_for_jobs_to_finish_for(5.seconds)
+      assert job_executed
+      assert_equal "Hawaii", job_executed_in_timezone
+    ensure
+      Time.zone = current_zone
+    end
+  end
+
   test "should run job with higher priority first" do
     skip unless adapter_is?(:delayed_job, :que)
 
diff --git a/activejob/test/jobs/timezone_dependent_job.rb b/activejob/test/jobs/timezone_dependent_job.rb
new file mode 100644
index 0000000000..41f473d533
--- /dev/null
+++ b/activejob/test/jobs/timezone_dependent_job.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require_relative "../support/job_buffer"
+
+class TimezoneDependentJob < ActiveJob::Base
+  def perform(now)
+    now = now.in_time_zone
+    new_year = localtime(2018, 1, 1)
+
+    if now >= new_year
+      JobBuffer.add("Happy New Year!")
+    else
+      JobBuffer.add("Just #{(new_year - now).div(3600)} hours to go")
+    end
+  end
+
+  private
+
+    def localtime(*args)
+      Time.zone ? Time.zone.local(*args) : Time.utc(*args)
+    end
+end
diff --git a/activejob/test/support/integration/dummy_app_template.rb b/activejob/test/support/integration/dummy_app_template.rb
index 7ea78c3350..b56dd3e591 100644
--- a/activejob/test/support/integration/dummy_app_template.rb
+++ b/activejob/test/support/integration/dummy_app_template.rb
@@ -21,6 +21,7 @@ class TestJob < ActiveJob::Base
     File.open(Rails.root.join("tmp/\#{x}.new"), "wb+") do |f|
       f.write Marshal.dump({
         "locale" => I18n.locale.to_s || "en",
+        "timezone" => Time.zone.try(:name) || "UTC",
         "executed_at" => Time.now.to_r
       })
     end
diff --git a/activejob/test/support/integration/test_case_helpers.rb b/activejob/test/support/integration/test_case_helpers.rb
index f02a32a38e..3d9b265b66 100644
--- a/activejob/test/support/integration/test_case_helpers.rb
+++ b/activejob/test/support/integration/test_case_helpers.rb
@@ -62,4 +62,8 @@ module TestCaseHelpers
     def job_executed_in_locale(id = @id)
       job_data(id)["locale"]
     end
+
+    def job_executed_in_timezone(id = @id)
+      job_data(id)["timezone"]
+    end
 end