Respond 409 for operation conflict instead of 500 (#6274)

#### What type of PR is this?

/kind improvement
/area core
/kind api-change
/milestone 2.18.x

#### What this PR does / why we need it:

This PR makes ConcurrencyFailureException respond http status code 409 instead of 500.

#### Which issue(s) this PR fixes:

Fixes #6254 

#### Does this PR introduce a user-facing change?

```release-note
None
```

application/src/main/java/run/halo/app/infra/exception/Exceptions.java

@@ -10,8 +10,11 @@ import java.util.Map;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.context.MessageSource;
 import org.springframework.core.annotation.MergedAnnotations;
+import org.springframework.dao.ConcurrencyFailureException;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.HttpStatusCode;
+import org.springframework.http.ProblemDetail;
+import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
 import org.springframework.security.authentication.BadCredentialsException;
 import org.springframework.web.ErrorResponse;
@@ -33,6 +36,9 @@ public enum Exceptions {
     public static final String REQUEST_NOT_PERMITTED_TYPE =
         "https://halo.run/probs/request-not-permitted";
 
+    public static final String CONFLICT_TYPE =
+        "https://halo.run/probs/conflict";
+
     /**
      * Non-ErrorResponse exception to type map.
      */
@@ -47,22 +53,11 @@ public enum Exceptions {
         if (t instanceof ErrorResponse er) {
             errorResponse = er;
         } else {
-            var responseStatusAnno =
-                MergedAnnotations.from(t.getClass(), TYPE_HIERARCHY).get(ResponseStatus.class);
-            if (status == null) {
-                status = responseStatusAnno.getValue("code", HttpStatus.class)
-                    .orElse(HttpStatus.INTERNAL_SERVER_ERROR);
+            var er = handleConflictException(t);
+            if (er == null) {
+                er = handleException(t, status);
             }
-            var type = EXCEPTION_TYPE_MAP.getOrDefault(t.getClass(), DEFAULT_TYPE);
-            var detail = responseStatusAnno.getValue("reason", String.class)
-                .orElseGet(t::getMessage);
-            var builder = ErrorResponse.builder(t, status, detail)
-                .type(URI.create(type));
-            if (status.is5xxServerError()) {
-                builder.detailMessageCode("problemDetail.internalServerError")
-                    .titleMessageCode("problemDetail.title.internalServerError");
-            }
-            errorResponse = builder.build();
+            errorResponse = er;
         }
         var problemDetail = errorResponse.updateAndGetBody(messageSource, getLocale(exchange));
         problemDetail.setInstance(exchange.getRequest().getURI());
@@ -71,6 +66,39 @@ public enum Exceptions {
         return errorResponse;
     }
 
+    @NonNull
+    private static ErrorResponse handleException(Throwable t, @Nullable HttpStatusCode status) {
+        var responseStatusAnno = MergedAnnotations.from(t.getClass(), TYPE_HIERARCHY)
+            .get(ResponseStatus.class);
+        if (status == null) {
+            status = responseStatusAnno.getValue("code", HttpStatus.class)
+                .orElse(HttpStatus.INTERNAL_SERVER_ERROR);
+        }
+        var type = EXCEPTION_TYPE_MAP.getOrDefault(t.getClass(), DEFAULT_TYPE);
+        var detail = responseStatusAnno.getValue("reason", String.class)
+            .orElseGet(t::getMessage);
+        var builder = ErrorResponse.builder(t, status, detail)
+            .type(URI.create(type));
+        if (status.is5xxServerError()) {
+            builder.detailMessageCode("problemDetail.internalServerError")
+                .titleMessageCode("problemDetail.title.internalServerError");
+        }
+        return builder.build();
+    }
+
+    @Nullable
+    private static ErrorResponse handleConflictException(Throwable t) {
+        if (t instanceof ConcurrencyFailureException) {
+            return ErrorResponse.builder(t, ProblemDetail.forStatus(HttpStatus.CONFLICT))
+                .type(URI.create(CONFLICT_TYPE))
+                .titleMessageCode("problemDetail.title.conflict")
+                .detailMessageCode("problemDetail.conflict")
+                .build();
+        }
+        return null;
+    }
+
+
     public static Locale getLocale(ServerWebExchange exchange) {
         var locale = exchange.getLocaleContext().getLocale();
         return locale == null ? Locale.getDefault() : locale;

application/src/main/resources/config/i18n/messages.properties

@@ -28,6 +28,7 @@ problemDetail.title.run.halo.app.infra.exception.PluginDependencyException$Wrong
 problemDetail.title.run.halo.app.infra.exception.PluginDependentsNotDisabledException=Dependents Not Disabled
 problemDetail.title.run.halo.app.infra.exception.PluginDependenciesNotEnabledException=Dependencies Not Enabled
 problemDetail.title.internalServerError=Internal Server Error
+problemDetail.title.conflict=Conflict
 
 # Detail definitions
 problemDetail.org.springframework.web.server.UnsupportedMediaTypeStatusException=Content type {0} is not supported. Supported media types: {1}.
@@ -72,6 +73,7 @@ problemDetail.directoryTraversal=Directory traversal detected. Base path is {0},
 problemDetail.plugin.version.unsatisfied.requires=Plugin requires a minimum system version of {0}, but the current version is {1}.
 problemDetail.plugin.missingManifest=Missing plugin manifest file "plugin.yaml" or manifest file does not conform to the specification.
 problemDetail.internalServerError=Something went wrong, please try again later.
+problemDetail.conflict=Conflict detected, please check the data and retry.
 problemDetail.migration.backup.notFound=The backup file does not exist or has been deleted.
 
 title.visibility.identification.private=(Private)

application/src/main/resources/config/i18n/messages_zh.properties

@@ -16,6 +16,7 @@ problemDetail.title.run.halo.app.infra.exception.PluginDependencyException$Wrong
 problemDetail.title.run.halo.app.infra.exception.PluginDependentsNotDisabledException=子插件未禁用
 problemDetail.title.run.halo.app.infra.exception.PluginDependenciesNotEnabledException=依赖未启用
 problemDetail.title.internalServerError=服务器内部错误
+problemDetail.title.conflict=冲突
 
 problemDetail.org.springframework.security.authentication.BadCredentialsException=用户名或密码错误。
 problemDetail.run.halo.app.infra.exception.AttachmentAlreadyExistsException=文件 {0} 已存在，建议更名后重试。
@@ -44,6 +45,7 @@ problemDetail.theme.version.unsatisfied.requires=主题要求一个最小的系
 problemDetail.theme.install.missingManifest=缺少 theme.yaml 配置文件或配置文件不符合规范。
 problemDetail.theme.install.alreadyExists=主题 {0} 已存在。
 problemDetail.internalServerError=服务器内部发生错误，请稍候再试。
+problemDetail.conflict=检测到冲突，请检查数据后重试。
 problemDetail.migration.backup.notFound=备份文件不存在或已删除。
 
 title.visibility.identification.private=（私有）

application/src/test/java/run/halo/app/infra/exception/handlers/I18nExceptionTest.java

@@ -10,12 +10,14 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.reactive.AutoConfigureWebTestClient;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.dao.ConcurrencyFailureException;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ProblemDetail;
 import org.springframework.http.ResponseEntity;
 import org.springframework.test.web.reactive.server.WebTestClient;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PutMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
@@ -117,6 +119,21 @@ class I18nExceptionTest {
             });
     }
 
+    @Test
+    void shouldGetConflictError() {
+        webClient.put().uri("/response-entity/conflict-error")
+            .header("X-XSRF-TOKEN", "fake-token")
+            .cookie("XSRF-TOKEN", "fake-token")
+            .exchange()
+            .expectStatus().isEqualTo(HttpStatus.CONFLICT)
+            .expectBody(ProblemDetail.class)
+            .value(problemDetail -> {
+                assertEquals("Conflict", problemDetail.getTitle());
+                assertEquals("Conflict detected.",
+                    problemDetail.getDetail());
+            });
+    }
+
     @TestConfiguration
     static class TestConfig {
 
@@ -156,6 +173,10 @@ class I18nExceptionTest {
                 throw new GeneralException("Something went wrong");
             }
 
+            @PutMapping("/conflict-error")
+            ResponseEntity<String> throwConflictException() {
+                throw new ConcurrencyFailureException("Conflict detected");
+            }
         }
     }
 

application/src/test/resources/application.yaml

@@ -12,7 +12,7 @@ spring:
       mode: always
       platform: h2
   messages:
-      basename: config.i18n.messages
+    basename: config.i18n.messages
 
 halo:
   work-dir: ${user.home}/halo-next-test

application/src/test/resources/config/i18n/messages.properties

@@ -3,4 +3,7 @@ problemDetail.internalServerError=Something went wrong, please try again later.
 
 problemDetail.run.halo.app.infra.exception.handlers.I18nExceptionTest$ErrorResponseException=Message argument is {0}.
 error.somethingWentWrong=Something went wrong, argument is {0}.
-problemDetail.title.internalServerError=Internal Server Error
+problemDetail.title.internalServerError=Internal Server Error
+
+problemDetail.title.conflict=Conflict
+problemDetail.conflict=Conflict detected.