payload should exposed as a Hash, fixes #4387

Changes.md

@@ -7,6 +7,7 @@ HEAD
 
 - Sidekiq Pro users will now see a Pause button next to each queue in
   the Web UI, allowing them to pause queues manually [#4374, shayonj]
+- Fix Sidekiq::Workers API unintentional change in 6.0.2 [#4387]
 
 
 6.0.3

lib/sidekiq/api.rb

@@ -926,7 +926,11 @@ module Sidekiq
           }
           next unless valid
           workers.each_pair do |tid, json|
-            yield key, tid, Sidekiq.load_json(json)
+            hsh = Sidekiq.load_json(json)
+            p = hsh["payload"]
+            # avoid breaking API, this is a side effect of the JSON optimization in #4316
+            hsh["payload"] = Sidekiq.load_json(p) if p.is_a?(String)
+            yield key, tid, hsh
           end
         end
       end

test/test_api.rb

@@ -580,7 +580,7 @@ describe 'API' do
       end
 
       s = "#{key}:workers"
-      data = Sidekiq.dump_json({ 'payload' => {}, 'queue' => 'default', 'run_at' => Time.now.to_i })
+      data = Sidekiq.dump_json({ 'payload' => "{}", 'queue' => 'default', 'run_at' => Time.now.to_i })
       Sidekiq.redis do |c|
         c.hmset(s, '1234', data)
       end
@@ -589,6 +589,7 @@ describe 'API' do
         assert_equal key, p
         assert_equal "1234", x
         assert_equal 'default', y['queue']
+        assert_equal({}, y['payload'])
         assert_equal Time.now.year, Time.at(y['run_at']).year
       end