prevent deadlocks with the connection pool

Author: hone

lib/resque/connection_pool.rb

@@ -34,6 +34,7 @@ def checkout
     def checkin(conn)
       @lock.synchronize do
         conns[conn] = false
+        @cv.broadcast
       end
     end
 

test/connection_pool_test.rb

@@ -93,5 +93,25 @@ def method_missing(meth, *args, &block)
 
       assert cp.checkout, "Connection should not be nil"
     end
+
+    it "avoids deadlocks" do
+      cp = ConnectionPool.new(REDIS_URL, 2)
+      cp.with_connection {|conn| conn.rpush(:foo, "hello") }
+
+      threads = []
+      5.times do
+        threads << Thread.new do
+          cp.with_connection do |conn|
+            conn.blpop(:foo, 1)
+          end
+        end
+      end
+
+      begin
+        threads.each {|t| t.join }
+      rescue Exception => e
+        refute_equal "fatal", e.class.to_s, e.message
+      end
+    end
   end
 end