samhap-soft · unifolio0 · Feb 12, 2026 · Feb 12, 2026 · Feb 12, 2026
diff --git a/external/src/main/java/com/samhap/kokomen/payment/external/TosspaymentsClient.java b/external/src/main/java/com/samhap/kokomen/payment/external/TosspaymentsClient.java
@@ -15,9 +15,10 @@ public TosspaymentsClient(TossPaymentsClientBuilder tossPaymentsClientBuilder) {
         this.restClient = tossPaymentsClientBuilder.getTossPaymentsClientBuilder().build();
     }
 
-    public TosspaymentsPaymentResponse confirmPayment(TosspaymentsConfirmRequest request) {
+    public TosspaymentsPaymentResponse confirmPayment(TosspaymentsConfirmRequest request, String idempotencyKey) {
         return restClient.post()
                 .uri("/v1/payments/confirm")
+                .header("Idempotency-Key", idempotencyKey)
                 .body(request)
                 .retrieve()
                 .body(TosspaymentsPaymentResponse.class);

diff --git a/internal/build.gradle b/internal/build.gradle
@@ -14,6 +14,7 @@ dependencies {
     implementation 'org.springframework.boot:spring-boot-starter-web'
     implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
     implementation 'org.springframework.boot:spring-boot-starter-validation'
+    implementation 'org.springframework.retry:spring-retry'
 
     runtimeOnly 'com.mysql:mysql-connector-j'
 

diff --git a/internal/src/main/java/com/samhap/kokomen/global/config/RetryConfig.java b/internal/src/main/java/com/samhap/kokomen/global/config/RetryConfig.java
@@ -0,0 +1,39 @@
+package com.samhap.kokomen.global.config;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.retry.backoff.ExponentialBackOffPolicy;
+import org.springframework.retry.support.RetryTemplate;
+
+@Configuration
+public class RetryConfig {
+
+    @Value("${retry.tosspayments.max-attempts}")
+    private int maxAttempts;
+
+    @Value("${retry.tosspayments.initial-interval}")
+    private long initialInterval;
+
+    @Value("${retry.tosspayments.multiplier}")
+    private double multiplier;
+
+    @Value("${retry.tosspayments.max-interval}")
+    private long maxInterval;
+
+    @Bean
+    public RetryTemplate tosspaymentsConfirmRetryTemplate() {
+        RetryTemplate retryTemplate = new RetryTemplate();
+
+        TosspaymentsConfirmRetryPolicy retryPolicy = new TosspaymentsConfirmRetryPolicy(maxAttempts);
+        retryTemplate.setRetryPolicy(retryPolicy);
+
+        ExponentialBackOffPolicy backOffPolicy = new ExponentialBackOffPolicy();
+        backOffPolicy.setInitialInterval(initialInterval);
+        backOffPolicy.setMultiplier(multiplier);
+        backOffPolicy.setMaxInterval(maxInterval);
+        retryTemplate.setBackOffPolicy(backOffPolicy);
+
+        return retryTemplate;
+    }
+}
diff --git a/internal/src/main/java/com/samhap/kokomen/global/config/TosspaymentsConfirmRetryPolicy.java b/internal/src/main/java/com/samhap/kokomen/global/config/TosspaymentsConfirmRetryPolicy.java
@@ -0,0 +1,36 @@
+package com.samhap.kokomen.global.config;
+
+import org.springframework.retry.RetryContext;
+import org.springframework.retry.policy.SimpleRetryPolicy;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.HttpServerErrorException;
+import org.springframework.web.client.ResourceAccessException;
+
+public class TosspaymentsConfirmRetryPolicy extends SimpleRetryPolicy {
+
+    public TosspaymentsConfirmRetryPolicy(int maxAttempts) {
+        super(maxAttempts);
+    }
+
+    @Override
+    public boolean canRetry(RetryContext context) {
+        Throwable lastException = context.getLastThrowable();
+        if (lastException != null && !isRetryableException(lastException)) {
+            return false;
+        }
+        return super.canRetry(context);
+    }
+
+    private boolean isRetryableException(Throwable throwable) {
+        if (throwable instanceof HttpServerErrorException) {
+            return true;
+        }
+        if (throwable instanceof ResourceAccessException) {
+            return true;
+        }
+        if (throwable instanceof HttpClientErrorException e) {
+            return e.getStatusCode().value() == 409;
+        }
+        return false;
+    }
+}
diff --git a/internal/src/main/java/com/samhap/kokomen/payment/service/PaymentFacadeService.java b/internal/src/main/java/com/samhap/kokomen/payment/service/PaymentFacadeService.java
@@ -16,8 +16,10 @@
 import com.samhap.kokomen.payment.service.dto.ConfirmRequest;
 import com.samhap.kokomen.payment.service.dto.PaymentResponse;
 import java.net.SocketTimeoutException;
+import java.util.UUID;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.retry.support.RetryTemplate;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.HttpServerErrorException;
@@ -31,6 +33,7 @@ public class PaymentFacadeService {
     private final TosspaymentsTransactionService tosspaymentsTransactionService;
     private final TosspaymentsPaymentService tosspaymentsPaymentService;
     private final TosspaymentsClient tosspaymentsClient;
+    private final RetryTemplate tosspaymentsConfirmRetryTemplate;
 
     public PaymentResponse confirmPayment(ConfirmRequest request) {
         TosspaymentsPayment tosspaymentsPayment = tosspaymentsPaymentService.saveTosspaymentsPayment(request);
@@ -40,20 +43,33 @@ public PaymentResponse confirmPayment(ConfirmRequest request) {
         } catch (KokomenException | HttpServerErrorException | ResourceAccessException e) {
             // inner에서 상태 처리 완료
             throw e;
-        }  catch (Exception e) {
+        } catch (Exception e) {
             // 예상치 못한 예외만 NEED_CANCEL 설정
             tosspaymentsPaymentService.updateState(tosspaymentsPayment.getId(), PaymentState.NEED_CANCEL);
             throw e;
         }
     }
 
-    private TosspaymentsPaymentResponse confirmPayment(ConfirmRequest request, TosspaymentsPayment tosspaymentsPayment) {
+    private TosspaymentsPaymentResponse confirmPayment(ConfirmRequest request,
+                                                       TosspaymentsPayment tosspaymentsPayment) {
+        String idempotencyKey = UUID.randomUUID().toString();
         try {
-            TosspaymentsPaymentResponse tosspaymentsConfirmResponse = tosspaymentsClient.confirmPayment(request.toTosspaymentsConfirmRequest());
-            tosspaymentsPayment.validateTosspaymentsResult(tosspaymentsConfirmResponse.paymentKey(), tosspaymentsConfirmResponse.orderId(),
+            TosspaymentsPaymentResponse tosspaymentsConfirmResponse = tosspaymentsConfirmRetryTemplate.execute(
+                    context -> {
+                        if (context.getRetryCount() > 0) {
+                            log.warn("토스페이먼츠 결제 승인 재시도 {}회차, paymentKey = {}",
+                                    context.getRetryCount(), request.paymentKey());
+                        }
+                        return tosspaymentsClient.confirmPayment(request.toTosspaymentsConfirmRequest(),
+                                idempotencyKey);
+                    });
+            tosspaymentsPayment.validateTosspaymentsResult(tosspaymentsConfirmResponse.paymentKey(),
+                    tosspaymentsConfirmResponse.orderId(),
                     tosspaymentsConfirmResponse.totalAmount());
-            TosspaymentsPaymentResult tosspaymentsPaymentResult = tosspaymentsConfirmResponse.toTosspaymentsPaymentResult(tosspaymentsPayment);
-            tosspaymentsTransactionService.applyTosspaymentsPaymentResult(tosspaymentsPaymentResult, PaymentState.COMPLETED);
+            TosspaymentsPaymentResult tosspaymentsPaymentResult = tosspaymentsConfirmResponse.toTosspaymentsPaymentResult(
+                    tosspaymentsPayment);
+            tosspaymentsTransactionService.applyTosspaymentsPaymentResult(tosspaymentsPaymentResult,
+                    PaymentState.COMPLETED);
             return tosspaymentsConfirmResponse;
         } catch (HttpClientErrorException e) {
             throw handleConfirmClientError(e, tosspaymentsPayment);
@@ -66,7 +82,8 @@ private TosspaymentsPaymentResponse confirmPayment(ConfirmRequest request, Tossp
         }
     }
 
-    private RuntimeException handleConfirmClientError(HttpClientErrorException e, TosspaymentsPayment tosspaymentsPayment) {
+    private RuntimeException handleConfirmClientError(HttpClientErrorException e,
+                                                      TosspaymentsPayment tosspaymentsPayment) {
         Failure failure = e.getResponseBodyAs(Failure.class);
         if (failure == null) {
             log.error("토스 결제 실패(400) - 응답 파싱 실패", e);
@@ -75,6 +92,12 @@ private RuntimeException handleConfirmClientError(HttpClientErrorException e, To
         }
         String code = failure.code();
 
+        if ("IDEMPOTENT_REQUEST_PROCESSING".equals(code)) {
+            log.error("토스 결제 처리 중 상태 지속 (409), paymentKey = {}", tosspaymentsPayment.getPaymentKey());
+            tosspaymentsPaymentService.updateState(tosspaymentsPayment.getId(), PaymentState.NEED_CANCEL);
+            return new InternalServerErrorException(PaymentServiceErrorMessage.CONFIRM_SERVER_ERROR.getMessage(), e);
+        }
+
         if (TosspaymentsInternalServerErrorCode.contains(code)) {
             log.error("토스 결제 실패(서버 원인 400), code = {}, message = {}", code, failure.message());
             tosspaymentsPaymentService.updateState(tosspaymentsPayment.getId(), PaymentState.SERVER_BAD_REQUEST);
@@ -87,11 +110,13 @@ private RuntimeException handleConfirmClientError(HttpClientErrorException e, To
     }
 
     private void handleConfirmServerError(HttpServerErrorException e, TosspaymentsPayment tosspaymentsPayment) {
-        // TODO: retry
         try {
-            TosspaymentsPaymentResponse tosspaymentsConfirmResponse = e.getResponseBodyAs(TosspaymentsPaymentResponse.class);
-            TosspaymentsPaymentResult tosspaymentsPaymentResult = tosspaymentsConfirmResponse.toTosspaymentsPaymentResult(tosspaymentsPayment);
-            tosspaymentsTransactionService.applyTosspaymentsPaymentResult(tosspaymentsPaymentResult, PaymentState.NEED_CANCEL);
+            TosspaymentsPaymentResponse tosspaymentsConfirmResponse = e.getResponseBodyAs(
+                    TosspaymentsPaymentResponse.class);
+            TosspaymentsPaymentResult tosspaymentsPaymentResult = tosspaymentsConfirmResponse.toTosspaymentsPaymentResult(
+                    tosspaymentsPayment);
+            tosspaymentsTransactionService.applyTosspaymentsPaymentResult(tosspaymentsPaymentResult,
+                    PaymentState.NEED_CANCEL);
         } catch (Exception parseException) {
             log.warn("토스 5xx 응답 파싱 실패, 상태만 업데이트합니다. paymentId = {}", tosspaymentsPayment.getId(), parseException);
             tosspaymentsPaymentService.updateState(tosspaymentsPayment.getId(), PaymentState.NEED_CANCEL);
@@ -101,12 +126,10 @@ private void handleConfirmServerError(HttpServerErrorException e, TosspaymentsPa
     private void handleConfirmNetworkError(ResourceAccessException e, TosspaymentsPayment tosspaymentsPayment) {
         if (e.getRootCause() instanceof SocketTimeoutException socketTimeoutException) {
             if (socketTimeoutException.getMessage().contains("Connect timed out")) {
-                // TODO: retry
                 tosspaymentsPaymentService.updateState(tosspaymentsPayment.getId(), PaymentState.CONNECTION_TIMEOUT);
                 return;
             }
             if (socketTimeoutException.getMessage().contains("Read timed out")) {
-                // TODO: retry
                 tosspaymentsPaymentService.updateState(tosspaymentsPayment.getId(), PaymentState.NEED_CANCEL);
                 return;
             }
@@ -115,17 +138,20 @@ private void handleConfirmNetworkError(ResourceAccessException e, TosspaymentsPa
     }
 
     public void cancelPayment(CancelRequest request) {
-        TosspaymentsPaymentCancelRequest tosspaymentsPaymentCancelRequest = new TosspaymentsPaymentCancelRequest(request.cancelReason());
+        TosspaymentsPaymentCancelRequest tosspaymentsPaymentCancelRequest = new TosspaymentsPaymentCancelRequest(
+                request.cancelReason());
         try {
-            TosspaymentsPaymentResponse response = tosspaymentsClient.cancelPayment(request.paymentKey(), tosspaymentsPaymentCancelRequest);
+            TosspaymentsPaymentResponse response = tosspaymentsClient.cancelPayment(request.paymentKey(),
+                    tosspaymentsPaymentCancelRequest);
             tosspaymentsTransactionService.applyCancelResult(response);
         } catch (HttpClientErrorException e) {
             Failure failure = e.getResponseBodyAs(Failure.class);
             if (failure == null) {
                 log.error("결제 취소 실패(400) - 응답 파싱 실패, paymentKey: {}", request.paymentKey(), e);
                 throw new InternalServerErrorException(PaymentServiceErrorMessage.CANCEL_SERVER_ERROR.getMessage(), e);
             }
-            log.error("결제 취소 실패(400) - paymentKey: {}, code: {}, message: {}", request.paymentKey(), failure.code(), failure.message());
+            log.error("결제 취소 실패(400) - paymentKey: {}, code: {}, message: {}", request.paymentKey(), failure.code(),
+                    failure.message());
             throw new BadRequestException(failure.message(), e);
         } catch (HttpServerErrorException e) {
             log.error("결제 취소 실패(5xx) - paymentKey: {}, status: {}", request.paymentKey(), e.getStatusCode());

diff --git a/internal/src/main/resources/application.yml b/internal/src/main/resources/application.yml
@@ -19,3 +19,33 @@ spring:
   config:
     activate:
       on-profile: local
+retry:
+  tosspayments:
+    max-attempts: 3
+    initial-interval: 500
+    multiplier: 2.0
+    max-interval: 2000
+---
+# dev profile
+spring:
+  config:
+    activate:
+      on-profile: dev
+retry:
+  tosspayments:
+    max-attempts: 3
+    initial-interval: 500
+    multiplier: 2.0
+    max-interval: 2000
+---
+# prod profile
+spring:
+  config:
+    activate:
+      on-profile: prod
+retry:
+  tosspayments:
+    max-attempts: 3
+    initial-interval: 500
+    multiplier: 2.0
+    max-interval: 2000