完善一下APIResponse的例子，兼容String作为返回值以及处理404错误

朱晔 · 朱晔 · commit edb293533fa2 · 2020-06-08T11:16:10.000+08:00
diff --git a/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/APIResponseAdvice.java b/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/APIResponseAdvice.java
@@ -1,6 +1,9 @@
 package org.geekbang.time.commonmistakes.apidesign.apiresponse;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.http.MediaType;
@@ -9,13 +12,16 @@
 import org.springframework.http.server.ServerHttpResponse;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.servlet.NoHandlerFoundException;
 import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;
 
 import javax.servlet.http.HttpServletRequest;
 
 @RestControllerAdvice
 @Slf4j
 public class APIResponseAdvice implements ResponseBodyAdvice<Object> {
+    @Autowired
+    private ObjectMapper objectMapper;
 
     //自动处理APIException，包装为APIResponse
     @ExceptionHandler(APIException.class)
@@ -28,6 +34,16 @@ public APIResponse handleApiException(HttpServletRequest request, APIException e
         return apiResponse;
     }
 
+    @ExceptionHandler(NoHandlerFoundException.class)
+    public APIResponse handleException(NoHandlerFoundException ex) {
+        log.error(ex.getMessage(), ex);
+        APIResponse apiResponse = new APIResponse();
+        apiResponse.setSuccess(false);
+        apiResponse.setCode(4000);
+        apiResponse.setMessage(ex.getMessage());
+        return apiResponse;
+    }
+
     //仅当方法或类没有标记@NoAPIResponse才自动包装
     @Override
     public boolean supports(MethodParameter returnType, Class converterType) {
@@ -37,13 +53,20 @@ public boolean supports(MethodParameter returnType, Class converterType) {
     }
 
     //自动包装外层APIResposne响应
+    @SneakyThrows
     @Override
     public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType, Class<? extends HttpMessageConverter<?>> selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) {
         APIResponse apiResponse = new APIResponse();
         apiResponse.setSuccess(true);
         apiResponse.setMessage("OK");
         apiResponse.setCode(2000);
         apiResponse.setData(body);
-        return apiResponse;
+        if (body instanceof String) {
+            response.getHeaders().setContentType(MediaType.APPLICATION_JSON);
+            return objectMapper.writeValueAsString(apiResponse);
+        } else {
+            return apiResponse;
+        }
+
     }
 }
diff --git a/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/APIResponseController.java b/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/APIResponseController.java
@@ -59,6 +59,11 @@ public OrderInfo server(@RequestParam("userId") Long userId) {
         return new OrderInfo("Created", 2L);
     }
 
+    @GetMapping("server2")
+    public String server2(@RequestParam("userId") Long userId) {
+        return userId + "OK";
+    }
+
     @GetMapping("client")
     @NoAPIResponse
     public String client(@RequestParam(value = "error", defaultValue = "0") int error) {
diff --git a/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/CommonMistakesApplication.java b/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/CommonMistakesApplication.java
@@ -1,12 +1,14 @@
 package org.geekbang.time.commonmistakes.apidesign.apiresponse;
 
+import org.geekbang.time.commonmistakes.common.Utils;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
 @SpringBootApplication
 public class CommonMistakesApplication {
 
     public static void main(String[] args) {
+        Utils.loadPropertySource(CommonMistakesApplication.class, "config.properties");
         SpringApplication.run(CommonMistakesApplication.class, args);
     }
 }
diff --git a/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/config.properties b/src/main/java/org/geekbang/time/commonmistakes/apidesign/apiresponse/config.properties
@@ -0,0 +1,2 @@
+spring.mvc.throw-exception-if-no-handler-found=true
+spring.resources.add-mappings=false

Original file line number	Diff line number	Diff line change
`@@ -1,12 +1,14 @@`
`1`	`1`	`package org.geekbang.time.commonmistakes.apidesign.apiresponse;`
`2`	`2`
	`3`	`+import org.geekbang.time.commonmistakes.common.Utils;`
`3`	`4`	`import org.springframework.boot.SpringApplication;`
`4`	`5`	`import org.springframework.boot.autoconfigure.SpringBootApplication;`
`5`	`6`
`6`	`7`	`@SpringBootApplication`
`7`	`8`	`public class CommonMistakesApplication {`
`8`	`9`
`9`	`10`	`public static void main(String[] args) {`
	`11`	`+ Utils.loadPropertySource(CommonMistakesApplication.class, "config.properties");`
`10`	`12`	`SpringApplication.run(CommonMistakesApplication.class, args);`
`11`	`13`	`}`
`12`	`14`	`}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+spring.mvc.throw-exception-if-no-handler-found=true`
	`2`	`+spring.resources.add-mappings=false`