美文网首页Spring-clound程序员
Spring Boot 静态资源文件配置

Spring Boot 静态资源文件配置

作者: 胖先森 | 来源:发表于2018-12-28 14:24 被阅读0次

    Spring Boot 静态资源文件配置

    说在前面的话:

    • 创建SpringBoot应用,选中我们需要的模块

    • SpringBoot已经默认将这些场景配置好了,只需要在配置文件中指定少量配置就可以运行起来

    • 自己编写业务代码

    由于 Spring Boot 采用了”约定优于配置”这种规范,所以在使用静态资源的时候也很简单。

    SpringBoot本质上是为微服务而生的,以JAR的形式启动运行,但是有时候静态资源的访问是必不可少的,比如:image、js、css 等资源的访问

    1.webjars配置静态路径

    简单了解即可,感觉实用性不大,

    public class WebMvcAutoConfiguration {
             public void addResourceHandlers(ResourceHandlerRegistry registry) {
                if (!this.resourceProperties.isAddMappings()) {
                    logger.debug("Default resource handling disabled");
                } else {
                    Duration cachePeriod = this.resourceProperties.getCache().getPeriod();
                    CacheControl cacheControl = this.resourceProperties.getCache().getCachecontrol().toHttpCacheControl();
                    if (!registry.hasMappingForPattern("/webjars/**")) {
                        this.customizeResourceHandlerRegistration(registry.addResourceHandler(new String[]{"/webjars/**"}).addResourceLocations(new String[]{"classpath:/META-INF/resources/webjars/"}).setCachePeriod(this.getSeconds(cachePeriod)).setCacheControl(cacheControl));
                    }
    
                    String staticPathPattern = this.mvcProperties.getStaticPathPattern();
                    if (!registry.hasMappingForPattern(staticPathPattern)) {
                        this.customizeResourceHandlerRegistration(registry.addResourceHandler(new String[]{staticPathPattern}).addResourceLocations(getResourceLocations(this.resourceProperties.getStaticLocations())).setCachePeriod(this.getSeconds(cachePeriod)).setCacheControl(cacheControl));
                    }
    
                }
            }
    }
    

    代码分析: 所有 /webjars/**,都去classpath:/META-INF/resources/webjars/找资源;webjars:以jar包的方式引入静态资源; webjars提供的依赖官网

    image
    <dependency>
        <groupId>org.webjars</groupId>
        <artifactId>jquery</artifactId>
        <version>1.12.4</version>
    </dependency>
    
    image

    启动服务,测试访问静态地址http://127.0.0.1:8001/hp/webjars/jquery/1.12.4/jquery.js

    2.默认静态资源路径

    @ConfigurationProperties(
        prefix = "spring.resources",
        ignoreUnknownFields = false
    )
    public class ResourceProperties {
        private static final String[] CLASSPATH_RESOURCE_LOCATIONS = new String[]{"classpath:/META-INF/resources/", "classpath:/resources/", "classpath:/static/", "classpath:/public/"};
        private String[] staticLocations;
        private boolean addMappings;
        private final ResourceProperties.Chain chain;
        private final ResourceProperties.Cache cache;
    
        public ResourceProperties() {
            this.staticLocations = CLASSPATH_RESOURCE_LOCATIONS;
            this.addMappings = true;
            this.chain = new ResourceProperties.Chain();
            this.cache = new ResourceProperties.Cache();
        }
    
        public String[] getStaticLocations() {
            return this.staticLocations;
        }
    }
    

    摘抄了部分源码,算是为了增加篇幅,从上述代码中我们可以看到,提供了几种默认的配置方式

    classpath:/static
    classpath:/public
    classpath:/resources
    classpath:/META-INF/resources
    备注说明: "/"=>当前项目的根路径
    

    我们在src/main/resources目录下新建 public、resources、static 、META-INF等目录目录,并分别放入 1.jpg 2.jpg 3.jpg 4.jpg 5.jpg 五张图片。

    image

    注意:需要排除webjars的形式,将pom.xml中的代码去掉,在进行测试结果结果如下

    image

    3.新增静态资源路径

    我们在spring.resources.static-locations后面追加一个配置classpath:/os/

    # 静态文件请求匹配方式
    spring.mvc.static-path-pattern=/**
    # 修改默认的静态寻址资源目录 多个使用逗号分隔
    spring.resources.static-locations = classpath:/META-INF/resources/,classpath:/resources/,classpath:/static/,classpath:/public/,classpath:/os/
    

    4.自定义静态资源映射

    在实际开发中,我们可能需要自定义静态资源访问以及上传路径,特别是文件上传,不可能上传的运行的JAR服务中,那么可以通过继承WebMvcConfigurerAdapter来实现自定义路径映射。

    application.properties 文件配置:

    # 图片音频上传路径配置(win系统自行变更本地路径)
    web.upload.path=D:/upload/attr/
    

    Demo05BootApplication.java 启动配置:

    package com.hanpang;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
    
    @SpringBootApplication
    public class Demo05BootApplication implements WebMvcConfigurer {
        private final static Logger LOGGER = LoggerFactory.getLogger(Demo05BootApplication.class);
    
        @Value("${web.upload.path}")
        private String uploadPath;
    
        @Override
        public void addResourceHandlers(ResourceHandlerRegistry registry) {
            registry.addResourceHandler("/uploads/**").addResourceLocations(
                    "file:" + uploadPath);
            LOGGER.info("自定义静态资源目录、此处功能用于文件映射");
        }
    
        public static void main(String[] args) {
            
            SpringApplication.run(Demo05BootApplication.class, args);
        }
    
    }
    

    5.设置欢迎界面

    依然从源码出手来解决这个问题

    public class WebMvcAutoConfiguration {
                private Optional<Resource> getWelcomePage() {
                String[] locations = getResourceLocations(this.resourceProperties.getStaticLocations());
                return Arrays.stream(locations).map(this::getIndexHtml).filter(this::isReadable).findFirst();
            }
    
            private Resource getIndexHtml(String location) {
                return this.resourceLoader.getResource(location + "index.html");
            }
    }
    

    5.1 直接设置静态默认页面

    欢迎页; 静态资源文件夹下的所有index.html页面,被"/**"映射;

    image

    5.2 增加控制器的方式

    • 新增模版引擎的支持

      <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-thymeleaf</artifactId>
      </dependency>
      
    • 配置核心文件application.properties

      server.port=8001
      server.servlet.context-path=/hp
      spring.mvc.view.prefix=classpath:/templates/
      

      没有去设置后缀名

    • 设置增加路由

      @Controller
      public class IndexController {
          @GetMapping({"/","/index"})
          public String index(){
              return "default";
          }
      }
      
    • 访问http://127.0.0.1:8001/hp/

    5.3 设置默认的View跳转页面

    • 新增模版引擎的支持

      <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-thymeleaf</artifactId>
      </dependency>
      
    • 配置核心文件application.properties

      server.port=8001
      server.servlet.context-path=/hp
      spring.mvc.view.prefix=classpath:/templates/
      

      没有去设置后缀名

    • 启动文件的修改如下

      @SpringBootApplication
      public class Demo05BootApplication implements WebMvcConfigurer {
          @Override
          public void addViewControllers(ViewControllerRegistry registry) {
              registry.addViewController("/").setViewName("default");
              registry.addViewController("/index1").setViewName("default");
              registry.setOrder(Ordered.HIGHEST_PRECEDENCE);
          }
      
          public static void main(String[] args) {
      
              SpringApplication.run(Demo05BootApplication.class, args);
          }
      
      }
      

    6. Favicon设置

     @Configuration
            @ConditionalOnProperty(
                value = {"spring.mvc.favicon.enabled"},
                matchIfMissing = true
            )
            public static class FaviconConfiguration implements ResourceLoaderAware {
                private final ResourceProperties resourceProperties;
                private ResourceLoader resourceLoader;
    
                public FaviconConfiguration(ResourceProperties resourceProperties) {
                    this.resourceProperties = resourceProperties;
                }
    
                public void setResourceLoader(ResourceLoader resourceLoader) {
                    this.resourceLoader = resourceLoader;
                }
    
                @Bean
                public SimpleUrlHandlerMapping faviconHandlerMapping() {
                    SimpleUrlHandlerMapping mapping = new SimpleUrlHandlerMapping();
                    mapping.setOrder(-2147483647);
                    mapping.setUrlMap(Collections.singletonMap("**/favicon.ico", this.faviconRequestHandler()));
                    return mapping;
                }
    
                @Bean
                public ResourceHttpRequestHandler faviconRequestHandler() {
                    ResourceHttpRequestHandler requestHandler = new ResourceHttpRequestHandler();
                    requestHandler.setLocations(this.resolveFaviconLocations());
                    return requestHandler;
                }
    
                private List<Resource> resolveFaviconLocations() {
                    String[] staticLocations = WebMvcAutoConfiguration.WebMvcAutoConfigurationAdapter.getResourceLocations(this.resourceProperties.getStaticLocations());
                    List<Resource> locations = new ArrayList(staticLocations.length + 1);
                    Stream var10000 = Arrays.stream(staticLocations);
                    ResourceLoader var10001 = this.resourceLoader;
                    var10001.getClass();
                    var10000.map(var10001::getResource).forEach(locations::add);
                    locations.add(new ClassPathResource("/"));
                    return Collections.unmodifiableList(locations);
                }
            }
    

    SpringBoot 默认是开启Favicon,并且提供了一个默认的Favicon,如果想关闭Favicon,只需要在application.properties中添加

    spring.mvc.favicon.enabled=false
    

    如果想更改Favicon,只需要将自己的Favicon.ico(文件名不能改动),放置到类路径根目录、类路径META_INF/resources/下、类路径resources/下、类路径static/下或者类路径public/下。

    5.附录

    A.WebMvcConfigurerAdapter过时

    在Springboot中配置WebMvcConfigurerAdapter的时候发现这个类过时了。所以看了下源码,发现官方在spring5弃用了WebMvcConfigurerAdapter,因为springboot2.0使用的spring5,所以会出现过时。

    WebMvcConfigurerAdapter已经过时,在新版本中被废弃,以下是比较常用的重写接口:

    /** 解决跨域问题 **/
    public void addCorsMappings(CorsRegistry registry) ;
    /** 添加拦截器 **/
    void addInterceptors(InterceptorRegistry registry);
    /** 这里配置视图解析器 **/
    void configureViewResolvers(ViewResolverRegistry registry);
    /** 配置内容裁决的一些选项 **/
    void configureContentNegotiation(ContentNegotiationConfigurer configurer);
    /** 视图跳转控制器 **/
    void addViewControllers(ViewControllerRegistry registry);
    /** 静态资源处理 **/
    void addResourceHandlers(ResourceHandlerRegistry registry);
    /** 默认静态资源处理器 **/
    void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer);
    

    方案1:直接实现WebMvcConfigurer

    @Configuration
    public class WebMvcConfg implements WebMvcConfigurer {
        @Override
        public void addViewControllers(ViewControllerRegistry registry) {
            registry.addViewController("/index").setViewName("index");
        }
    }
    

    方案2:直接继承WebMvcConfigurationSupport

    @Configuration
    public class WebMvcConfg extends WebMvcConfigurationSupport {
        @Override
        public void addViewControllers(ViewControllerRegistry registry) {
            registry.addViewController("/index").setViewName("index");
        }
    }
    

    其实,源码下WebMvcConfigurerAdapter是实现WebMvcConfigurer接口,所以直接实现WebMvcConfigurer接口也可以;WebMvcConfigurationSupport与WebMvcConfigurerAdapter、接口WebMvcConfigurer处于同一个目录下WebMvcConfigurationSupport包含WebMvcConfigurer里面的方法,由此看来版本中应该是推荐使用WebMvcConfigurationSupport类的,WebMvcConfigurationSupport应该是新版本中对WebMvcConfigurerAdapter的替换和扩展

    B.关于加载目录问题

    // 可以直接使用addResourceLocations 指定磁盘绝对路径,同样可以配置多个位置,注意路径写法需要加上file:
    registry.addResourceHandler("/myimgs/**").addResourceLocations("file:H:/myimgs/");
    
    // 访问myres根目录下的fengjing.jpg 的URL为 http://localhost:8080/fengjing.jpg (/** 会覆盖系统默认的配置)
    registry.addResourceHandler("/**").addResourceLocations("classpath:/myres/").addResourceLocations("classpath:/static/");
    

    相关文章

      网友评论

        本文标题:Spring Boot 静态资源文件配置

        本文链接:https://www.haomeiwen.com/subject/huwslqtx.html