SpringBootBlog/src/main/java/cc/bnblogs/config/WebConfig.java

package cc.bnblogs.config;

import cc.bnblogs.common.LRUCache;
import cc.bnblogs.interceptor.LoginInterceptor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.server.ConfigurableWebServerFactory;
import org.springframework.boot.web.server.ErrorPage;
import org.springframework.boot.web.server.WebServerFactoryCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpStatus;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.io.File;

/**
 * @author zfp@bnblogs.cc
 * @createTime: 2022/10/16
 */
@Slf4j
@Configuration
public class WebConfig implements WebMvcConfigurer {

    @Value("${upload.base-dir}")
    private String baseDir;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // 注册拦截器，添加拦截路由和放行路由
        registry.addInterceptor(loginInterceptor)
                .addPathPatterns("/admin/**")
                .excludePathPatterns("/admin/login","/admin/logout","/admin/login.html");
    }

    private final LoginInterceptor loginInterceptor;

    public static final Integer MAX_LRU_CACHE_SIZE = 20;

    public WebConfig(LoginInterceptor loginInterceptor) {
        this.loginInterceptor = loginInterceptor;
    }


    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        // 创建static目录到/static/的路由
        // 即改为localhost:8080/static/image/1.jpg. 而不是原来的localhost:8080/image/1.jpg
        registry.addResourceHandler("/static/**").
                addResourceLocations("classpath:/static/");
        File dir = new File(baseDir);
        if (!dir.isDirectory()) {
            // 创建文件保存目录
            dir.mkdirs();
        }
        String absolutePath = dir.getAbsolutePath().replace("./", "") + "/";
        log.info("absolutePath:{}", absolutePath);
        //  一定要在绝对路径前加上file://表明它是一个本地目录
        // !!!!!!
        // 记住在absolutePath前加一个'/',否则本地图片读取不出来(重要的事情说三遍)
        registry.addResourceHandler("/upload/**").addResourceLocations("file://" + '/' + absolutePath);
    }

    /**
     * 错误页面配置是根据HTTP请求返回的状态码决定的(Http异常)
     * Controller层的报错是thymeleaf渲染页面时报错的(业务异常)
     * @return 跳转到对应的error页面
     */
    @Bean
    public WebServerFactoryCustomizer<ConfigurableWebServerFactory> webServerFactoryCustomizer() {
        return factory -> factory.addErrorPages(
                new ErrorPage(HttpStatus.NOT_FOUND, "/error/404.html"),
                new ErrorPage(HttpStatus.INTERNAL_SERVER_ERROR, "/error/500.html"));
    }
    @Bean
    public LRUCache lruCache() {
        return new LRUCache(MAX_LRU_CACHE_SIZE);
    }
}