Add AsDuplicateRequestError function

common/persistence/errors.go

@@ -22,7 +22,10 @@
 
 package persistence
 
-import "fmt"
+import (
+	"errors"
+	"fmt"
+)
 
 type (
 	// TimeoutError is returned when a write operation fails due to a timeout
@@ -121,3 +124,11 @@ func (e *DBUnavailableError) Error() string {
 func (e *TransactionSizeLimitError) Error() string {
 	return e.Msg
 }
+
+func AsDuplicateRequestError(err error) (*DuplicateRequestError, bool) {
+	var e *DuplicateRequestError
+	if errors.As(err, &e) {
+		return e, true
+	}
+	return nil, false
+}

common/persistence/errors_test.go

@@ -0,0 +1,67 @@
+// The MIT License (MIT)
+
+// Copyright (c) 2017-2020 Uber Technologies Inc.
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package persistence
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAsDuplicateRequestError(t *testing.T) {
+	testCases := []struct {
+		name        string
+		err         error
+		expectedErr *DuplicateRequestError
+		ok          bool
+	}{
+		{
+			name:        "unwrapped",
+			err:         &DuplicateRequestError{RunID: "a"},
+			expectedErr: &DuplicateRequestError{RunID: "a"},
+			ok:          true,
+		},
+		{
+			name:        "wrapped",
+			err:         fmt.Errorf("%w", &DuplicateRequestError{RunID: "b"}),
+			expectedErr: &DuplicateRequestError{RunID: "b"},
+			ok:          true,
+		},
+		{
+			name: "not same type",
+			err:  fmt.Errorf("adasdf"),
+			ok:   false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			e, ok := AsDuplicateRequestError(tc.err)
+			assert.Equal(t, tc.ok, ok)
+			if ok {
+				assert.Equal(t, tc.expectedErr, e)
+			}
+		})
+	}
+}

service/history/engine/engineimpl/historyEngine.go

@@ -789,7 +789,7 @@ func (e *historyEngineImpl) startWorkflowHelper(
 		prevLastWriteVersion,
 		persistence.CreateWorkflowRequestModeNew,
 	)
-	if t, ok := err.(*persistence.DuplicateRequestError); ok {
+	if t, ok := persistence.AsDuplicateRequestError(err); ok {
 		if t.RequestType == persistence.WorkflowRequestTypeStart || (isSignalWithStart && t.RequestType == persistence.WorkflowRequestTypeSignal) {
 			return &types.StartWorkflowExecutionResponse{
 				RunID: t.RunID,
@@ -865,7 +865,7 @@ func (e *historyEngineImpl) startWorkflowHelper(
 			t.LastWriteVersion,
 			persistence.CreateWorkflowRequestModeNew,
 		)
-		if t, ok := err.(*persistence.DuplicateRequestError); ok {
+		if t, ok := persistence.AsDuplicateRequestError(err); ok {
 			if t.RequestType == persistence.WorkflowRequestTypeStart || (isSignalWithStart && t.RequestType == persistence.WorkflowRequestTypeSignal) {
 				return &types.StartWorkflowExecutionResponse{
 					RunID: t.RunID,
@@ -2640,7 +2640,7 @@ func (e *historyEngineImpl) SignalWithStartWorkflowExecution(
 			// We apply the update to execution using optimistic concurrency.  If it fails due to a conflict then reload
 			// the history and try the operation again.
 			if err := wfContext.UpdateWorkflowExecutionAsActive(ctx, e.shard.GetTimeSource().Now()); err != nil {
-				if t, ok := err.(*persistence.DuplicateRequestError); ok {
+				if t, ok := persistence.AsDuplicateRequestError(err); ok {
 					if t.RequestType == persistence.WorkflowRequestTypeSignal {
 						return &types.StartWorkflowExecutionResponse{RunID: t.RunID}, nil
 					}
@@ -3041,7 +3041,7 @@ func (e *historyEngineImpl) ResetWorkflowExecution(
 		nil,
 		request.GetSkipSignalReapply(),
 	); err != nil {
-		if t, ok := err.(*persistence.DuplicateRequestError); ok {
+		if t, ok := persistence.AsDuplicateRequestError(err); ok {
 			if t.RequestType == persistence.WorkflowRequestTypeReset {
 				return &types.ResetWorkflowExecutionResponse{
 					RunID: t.RunID,