【Spring Security開發安全的REST服務】-3.6 服務異常處理

一、概述

二、SpringBoot默認的錯誤處理機制

2.1、模擬不同客戶端訪問不存在的url

SpringBoot已經爲不同的方式訪問Restful API配置了一套默認的錯誤處理機制。

2.1.1、Web端訪問不存在的url的處理機制

訪問一個Http:localhost:8080/xxx；在SpringBoot的默認錯誤頁上標識了當前錯誤信息。

2.1.2、模擬App使用接口方式訪問不存在的url的處理機制

可以看到訪問返回的是一個JSON格式

2.2、分析SpringBoot的默認處理機制源碼（BasicErrorController）

下面是BasicErrorController類的源碼，從下面這個類可以看到這是一個控制器類，主要有兩個方法，一個方法在方法頭部添加了

@RequestMapping(
        produces = {"text/html"}
    )

當我們請求頭中帶有text/html時會調用這個方法，當沒有的時候就會調用另一個方法。

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package org.springframework.boot.autoconfigure.web.servlet.error;

import java.util.Collections;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.boot.autoconfigure.web.ErrorProperties;
import org.springframework.boot.autoconfigure.web.ErrorProperties.IncludeStacktrace;
import org.springframework.boot.web.servlet.error.ErrorAttributes;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.util.Assert;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping({"${server.error.path:${error.path:/error}}"})
public class BasicErrorController extends AbstractErrorController {
    private final ErrorProperties errorProperties;

    public BasicErrorController(ErrorAttributes errorAttributes, ErrorProperties errorProperties) {
        this(errorAttributes, errorProperties, Collections.emptyList());
    }

    public BasicErrorController(ErrorAttributes errorAttributes, ErrorProperties errorProperties, List<ErrorViewResolver> errorViewResolvers) {
        super(errorAttributes, errorViewResolvers);
        Assert.notNull(errorProperties, "ErrorProperties must not be null");
        this.errorProperties = errorProperties;
    }

    public String getErrorPath() {
        return this.errorProperties.getPath();
    }

    @RequestMapping(
        produces = {"text/html"}
    )
    public ModelAndView errorHtml(HttpServletRequest request, HttpServletResponse response) {
        HttpStatus status = this.getStatus(request);
        Map<String, Object> model = Collections.unmodifiableMap(this.getErrorAttributes(request, this.isIncludeStackTrace(request, MediaType.TEXT_HTML)));
        response.setStatus(status.value());
        ModelAndView modelAndView = this.resolveErrorView(request, response, status, model);
        return modelAndView != null ? modelAndView : new ModelAndView("error", model);
    }

    @RequestMapping
    public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
        Map<String, Object> body = this.getErrorAttributes(request, this.isIncludeStackTrace(request, MediaType.ALL));
        HttpStatus status = this.getStatus(request);
        return new ResponseEntity(body, status);
    }

    protected boolean isIncludeStackTrace(HttpServletRequest request, MediaType produces) {
        IncludeStacktrace include = this.getErrorProperties().getIncludeStacktrace();
        if (include == IncludeStacktrace.ALWAYS) {
            return true;
        } else {
            return include == IncludeStacktrace.ON_TRACE_PARAM ? this.getTraceParameter(request) : false;
        }
    }

    protected ErrorProperties getErrorProperties() {
        return this.errorProperties;
    }
}