From 3f4c37e92adaeef1ed7380f6afa013bceeeca5bc Mon Sep 17 00:00:00 2001
From: Rick Bradley <bradley@github.com>
Date: Tue, 26 Feb 2013 17:04:18 -0600
Subject: [PATCH 1/2] Add :timestamp to publish payload

Now we can track when a particular result occurred.
---
 lib/dat/science/experiment.rb       | 3 +++
 test/dat_science_experiment_test.rb | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/lib/dat/science/experiment.rb b/lib/dat/science/experiment.rb
index 49e7d92..7424cb7 100644
--- a/lib/dat/science/experiment.rb
+++ b/lib/dat/science/experiment.rb
@@ -50,6 +50,8 @@ module Dat
       def run
         return run_control unless candidate? && enabled?
 
+        timestamp = Time.now
+
         if control_runs_first?
           control   = observe_control
           candidate = observe_candidate
@@ -59,6 +61,7 @@ module Dat
         end
 
         payload = {
+          :timestamp => timestamp,
           :candidate => candidate.payload,
           :control   => control.payload,
           :first     => control_runs_first? ? :control : :candidate
diff --git a/test/dat_science_experiment_test.rb b/test/dat_science_experiment_test.rb
index d83d005..0e7625c 100644
--- a/test/dat_science_experiment_test.rb
+++ b/test/dat_science_experiment_test.rb
@@ -106,6 +106,8 @@ class DatScienceExperimentTest < MiniTest::Unit::TestCase
     assert_equal "foo", payload[:experiment]
     assert_equal :control, payload[:first]
 
+    assert (Time.now.to_i - payload[:timestamp].to_i) < 10
+
     assert payload[:control][:duration]
     assert_nil payload[:control][:exception]
     assert_equal :foo, payload[:control][:value]

From 59700248c4ab97ec4fed5091c8ab101dd8c67d3e Mon Sep 17 00:00:00 2001
From: Rick Bradley <bradley@github.com>
Date: Tue, 26 Feb 2013 17:20:27 -0600
Subject: [PATCH 2/2] go with assert_in_delta to make :timestamp test palatable

---
 test/dat_science_experiment_test.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/dat_science_experiment_test.rb b/test/dat_science_experiment_test.rb
index 0e7625c..1ec97da 100644
--- a/test/dat_science_experiment_test.rb
+++ b/test/dat_science_experiment_test.rb
@@ -106,7 +106,7 @@ class DatScienceExperimentTest < MiniTest::Unit::TestCase
     assert_equal "foo", payload[:experiment]
     assert_equal :control, payload[:first]
 
-    assert (Time.now.to_i - payload[:timestamp].to_i) < 10
+    assert_in_delta Time.now.to_f, payload[:timestamp].to_f, 2.0
 
     assert payload[:control][:duration]
     assert_nil payload[:control][:exception]