选项 Http 请求因 404 异常而失败，而 Post 请求工作正常

Question

我在 spring 框架中有一个带有可选 PathVariable 的休息端点。

@PostMapping("/API_PATH/{param1}/{param2}")
public Result getResult(@PathVariable Integer param1,
    @PathVariable(required = false) Integer param2, @RequestBody Data data) {
    // SOME LOGIC HERE
}

我已将param2 Path 变量标记为不需要。 所以它是一个可选值。 当我不向param2发送任何值时，此 POST API 工作正常。 但是当浏览器尝试访问这个 API 时，它会在发送实际的POST请求之前发送一个OPTIONS类型的请求。 现在，如果OPTIONS reqeust 不包含 URL 中的第二个路径变量 ( param2 )，则它会因 404 异常而失败。 有没有办法解决这个问题？

Answer 1

OPTIONS 请求是我们在跨域资源共享 (CORS) 中称为检查安全措施的飞行前请求。 同样，您可能需要添加 CORS 配置

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
@EnableWebMvc
public class WebConfig implements Filter,WebMvcConfigurer {

    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**");
    }

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) {
      HttpServletResponse response = (HttpServletResponse) res;
      HttpServletRequest request = (HttpServletRequest) req;
      System.out.println("WebConfig; "+request.getRequestURI());
      response.setHeader("Access-Control-Allow-Origin", "*");
      response.setHeader("Access-Control-Allow-Methods", "POST, PUT, GET, OPTIONS, DELETE");
      response.setHeader("Access-Control-Allow-Headers", "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With,observe");
      response.setHeader("Access-Control-Max-Age", "3600");
      response.setHeader("Access-Control-Allow-Credentials", "true");
      response.setHeader("Access-Control-Expose-Headers", "Authorization");
      response.addHeader("Access-Control-Expose-Headers", "responseType");
      response.addHeader("Access-Control-Expose-Headers", "observe");
      System.out.println("Request Method: "+request.getMethod());
      if (!(request.getMethod().equalsIgnoreCase("OPTIONS"))) {
          try {
              chain.doFilter(req, res);
          } catch(Exception e) {
              e.printStackTrace();
          }
      } else {
          System.out.println("Pre-flight");
          response.setHeader("Access-Control-Allow-Origin", "*");
          response.setHeader("Access-Control-Allow-Methods", "POST,GET,DELETE,PUT");
          response.setHeader("Access-Control-Max-Age", "3600");
          response.setHeader("Access-Control-Allow-Headers", "Access-Control-Expose-Headers"+"Authorization, content-type," +
          "USERID"+"ROLE"+
                  "access-control-request-headers,access-control-request-method,accept,origin,authorization,x-requested-with,responseType,observe");
          response.setStatus(HttpServletResponse.SC_OK);
      }

    }

}

---

使用CorsRegistry配置 CORS 的其他一些方法：

@Override
public void addCorsMappings(CorsRegistry registry) {
    registry.addMapping("/api/**")
        .allowedOrigins("http://domain1.com","http://domain2.com");
}

---

使用@CrossOrigin ：

@CrossOrigin(origins = {"http://domain1.com","http://domain2.com"})

---

使用application.properties

management.endpoints.web.cors.allowed-origins=http://domain1.com,http://domain2.com

Answer 2

您的代码专门用于POST ，因此没有OPTIONS处理程序。 Spring 提供了一个实现飞行前 CORS 处理程序的CrossOrigin注释，请在此处阅读。

尝试这个：

@CrossOrigin
@PostMapping("/API_PATH/{param1}/{param2}")
public Result getResult(@PathVariable Integer param1,
@PathVariable(required = false) Integer param2, @RequestBody Data data) {
    // SOME LOGIC HERE
}