springboot中动态api如何设置

1.不需要编写controller 等mvc层，通过接口动态生成api。

这个问题，其实很好解决，以前编写接口，是要写controller，需要有

@RestController
@RequestMapping("/test1")
public class xxxController{
@ApiOperation("测试预览")@PostMapping("/test2")public Object test(String name) throws Exception {
}
}

在这个总开关类里面dispacherServlet这个类里面是需要解析的，
从doDispatch方法开始解析（只贴需要的代码）

protected void doDispatch(HttpServletRequest request, HttpServletResponse response) throws Exception {
// Determine handler for the current request.//1.这个方法就是执行了寻找对应的类实例和方法名mappedHandler = getHandler(processedRequest);if (mappedHandler == null) {// 找不到会报错，就是常见的404，没有找到xxx/xxx方法映射，noHandlerFound(processedRequest, response);return;}
}

然后ctrl点进去
mappedHandler = getHandler(processedRequest);
这个方法
来到：

@Nullableprotected HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {if (this.handlerMappings != null) {// 从这里便利找for (HandlerMapping mapping : this.handlerMappings) {HandlerExecutionChain handler = mapping.getHandler(request);if (handler != null) {return handler;}}}return null;}

HandlerMapping 它就长这样子
在这里插入图片描述
其中绿色的这个就是我们写的什么controller啥的地址啦还有对应得方法，在里面。

2.重点

从上图看这个红色就是我们要写的一个了，因为为什么呢，你要动态的，绿色代码里你都没写。是springboot你写了controller代码它自动扫描到的，所以你得自己配一个进去。这样子就能够实现动态解析了。

3.基于以上简单的介绍，那就可以开始了，说白了就是模范写一个进去，让springboot能够识别。他原生自带的不行，咱就给它

RequstMappingHandlerMapping 就是模仿这个类写一个。

先看这个类长啥样：

public class RequestMappingHandlerMapping extends RequestMappingInfoHandlerMappingimplements MatchableHandlerMapping, EmbeddedValueResolverAware {}

继承还挺多，完了我们也写一个,主要实现这个方法即可lookupHandlerMethod（），这个就是怎么找对应地址和方法的逻辑

@Component
public class CustomHandlerMapping extends RequestMappingInfoHandlerMappingimplements MatchableHandlerMapping, Ordered {@Autowiredprivate List<HandlerMethodArgumentResolver> argumentResolvers; // 注入Spring Boot自带的参数解析器@Overrideprotected HandlerMethod lookupHandlerMethod(String lookupPath, HttpServletRequest request) throws Exception {// 根据请求路径动态返回对应的处理器方法if (lookupPath.startsWith("/test")) {Object handler = getApplicationContext().getBean(CustomHandler.class);return new HandlerMethod(handler, "handleTestRequest", HttpServletRequest.class, HttpServletResponse.class);}return null;}@Overrideprotected HandlerExecutionChain getHandlerExecutionChain(Object handler, HttpServletRequest request) {HandlerExecutionChain chain = super.getHandlerExecutionChain(handler, request);
//        System.out.println(super.getAdaptedInterceptors());
//        chain.addInterceptor(new ApiInterceptor()); // 注册自定义拦截器List<HandlerInterceptor> interceptors = new ArrayList<>();return chain;}@Overrideprotected boolean isHandler(Class<?> beanType) {return false;}@Overrideprotected RequestMappingInfo getMappingForMethod(Method method, Class<?> handlerType) {return null;}@Overridepublic RequestMatchResult match(HttpServletRequest request, String pattern) {System.out.println(request);System.out.println(pattern);return null;}@Overridepublic int getOrder() {return Integer.MAX_VALUE;}
}

还有一个具体的业务逻辑

@Component
@Slf4j
public class CustomHandler {public void handleTestRequest(HttpServletRequest request, HttpServletResponse response) {// 在这里编写处理特定请求的逻辑// 例如，可以根据请求参数、请求头等信息进行动态处理try {log.info("方法："+request.getMethod());log.info("参数："+request.getParameterMap().values());response.setCharacterEncoding("UTF-8");response.setContentType("application/json; charset=utf-8");// 跨域设置response.setHeader("Access-Control-Allow-Origin", "*");response.setHeader("Access-Control-Allow-Credentials", "true");response.setHeader("Access-Control-Allow-Headers", "Authorization");//这里很重要，要不然js header不能跨域携带  Authorization属性response.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS, DELETE");response.getWriter().write(JSON.toJSONString(ResultBody.ok().data("你好")));} catch (IOException e) {// 处理异常}}
}