add check to clear errors on first success if

error_threshold_timeout_enabled false

Author: abishanan-shopify

lib/semian/circuit_breaker.rb

@@ -77,10 +77,14 @@ def mark_failed(error)
     end
 
     def mark_success
-      return unless half_open?
-
-      @successes.increment
-      transition_to_close if success_threshold_reached?
+      if half_open?
+        @successes.increment
+        if success_threshold_reached?
+          transition_to_close
+        end
+      else
+        @errors.clear unless error_threshold_timeout_enabled
+      end
     end
 
     def reset

test/circuit_breaker_test.rb

@@ -87,9 +87,17 @@ def test_once_success_threshold_is_reached_only_error_threshold_will_open_the_ci
     )
     half_open_cicuit!(resource)
 
+    STDERR.puts "resource.errors: #{resource.circuit_breaker.instance_variable_get(:@errors).size}"
+    STDERR.puts "circuit state: #{resource.circuit_breaker.state.value}"
+    STDERR.puts "error timeout expired: #{resource.circuit_breaker.send(:error_timeout_expired?)}"
+
     assert_circuit_closed(resource)
     trigger_error!(resource)
 
+    STDERR.puts "resource.errors: #{resource.circuit_breaker.instance_variable_get(:@errors).size}"
+    STDERR.puts "circuit state: #{resource.circuit_breaker.state.value}"
+    STDERR.puts "error timeout expired: #{resource.circuit_breaker.send(:error_timeout_expired?)}"
+
     assert_circuit_closed(resource)
     trigger_error!(resource)
 

test/helpers/circuit_breaker_helper.rb

@@ -22,8 +22,24 @@ def trigger_error!(resource = @resource, error = SomeError)
 
   def assert_circuit_closed(resource = @resource)
     block_called = false
+
+    circuit_breaker = resource.circuit_breaker
+
+    old_errors = create_sliding_window_copy(circuit_breaker.instance_variable_get(:@errors))
+    previously_half_open = circuit_breaker&.send(:half_open?)
+
     resource.acquire { block_called = true }
 
+    STDERR.puts "old_errors: #{old_errors.size}"
+    STDERR.puts "new_errors: #{circuit_breaker.instance_variable_get(:@errors).size}"
+
+    unless previously_half_open || circuit_breaker.instance_variable_get(:@error_threshold_timeout_enabled).nil? || circuit_breaker.instance_variable_get(:@error_threshold_timeout_enabled)
+      circuit_breaker.instance_variable_set(:@errors, old_errors)
+    end
+
+    STDERR.puts "previously_half_open: #{previously_half_open}"
+    STDERR.puts "error_threshold_timeout_enabled: #{circuit_breaker.instance_variable_get(:@error_threshold_timeout_enabled)}"
+
     assert(block_called, "Expected the circuit to be closed, but it was open")
   end
 
@@ -37,4 +53,21 @@ def assert_circuit_opened(resource = @resource)
 
     assert(open, "Expected the circuit to be open, but it was closed")
   end
+
+  def create_sliding_window_copy(sliding_window)
+    return if sliding_window.nil?
+
+    implementation_class = sliding_window.class
+
+    new_window = implementation_class.new(max_size: sliding_window.max_size)
+
+    if sliding_window.respond_to?(:size) && !sliding_window.empty?
+      original_data = sliding_window.instance_variable_get(:@window)
+      if original_data.is_a?(Array)
+        new_window.instance_variable_set(:@window, original_data.dup)
+      end
+    end
+
+    new_window
+  end
 end