VersionResourceResolver会破坏CSS相对URL

Question

我在Spring Boot 1.2.2中使用VersionResourceResolver进行缓存清除.不幸的是,它认为操纵CSS文件中指定的URI很聪明.

以Twitters Bootstrap为例.它在CSS文件所在目录上方的目录中查找字体.

@font-face {
  font-family: 'Glyphicons Halflings';

  src: url('../fonts/glyphicons-halflings-regular.eot');
  src: url('../fonts/glyphicons-halflings-regular.eot?#iefix') format('embedded-opentype'), url('../fonts/glyphicons-halflings-regular.woff2') format('woff2'), url('../fonts/glyphicons-halflings-regular.woff') format('woff'), url('../fonts/glyphicons-halflings-regular.ttf') format('truetype'), url('../fonts/glyphicons-halflings-regular.svg#glyphicons_halflingsregular') format('svg');
}

没有VersionResourceResolver,它就像预期的那样工作:

GET http://example.com/res/css/bootstrap.min.css
GET http://example.com/res/fonts/glyphicons-halflings-regular.woff

现在我添加VersionResourceResolver:

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/res/**")
            .addResourceLocations("/resources/")
            .setCachePeriod(CACHE_SECONDS)
            .resourceChain(true)
                .addResolver(new VersionResourceResolver()                      
                .addFixedVersionStrategy(buildVersion, "/**/"))
                .addResolver(new PathResourceResolver());       
}

现在这发生了:

GET http://example.com/res/085a8/css/bootstrap.min.css
GET http://example.com/res/085a8/css/fonts/glyphicons-halflings-regular.woff

那么,为什么会这样呢？因为有人篡改了CSS文件中的URI:

@font-face {
  font-family: 'Glyphicons Halflings';

  src: url('085a8/../fonts/glyphicons-halflings-regular.eot');
  src: url('../fonts/glyphicons-halflings-regular.eot?#iefix') format('embedded-opentype'), url('085a8/../fonts/glyphicons-halflings-regular.woff2') format('woff2'), url('085a8/../fonts/glyphicons-halflings-regular.woff') format('woff'), url('085a8/../fonts/glyphicons-halflings-regular.ttf') format('truetype'), url('../fonts/glyphicons-halflings-regular.svg#glyphicons_halflingsregular') format('svg');
}

Bootstrap只是一个例子.对于CSS资源中指定的几乎所有(奇怪的并非全部)URI都会发生这种情况.使用Spring的CssLinkResourceTransformer没有帮助.那么,我如何告诉Spring不要操纵CSS文件？

编辑:我发现,Spring调用了CssLinkResourceTransformer.但我没有在任何地方指明.可能是Spring Boot在某处自动配置.

03-05 16:12:47.711 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Transforming resource: ServletContext resource [/resources/css/bootstrap.min.css]
2015-03-05 16:12:47.716 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Link modified: 77a6e2aa77283c05d58f4ab52102f55684b6fb04/../fonts/glyphicons-halflings-regular.eot (original: ../fonts/glyphicons-halflings-regular.eot)
2015-03-05 16:12:47.716 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Link not modified: ../fonts/glyphicons-halflings-regular.eot?#iefix
2015-03-05 16:12:47.717 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Link modified: 77a6e2aa77283c05d58f4ab52102f55684b6fb04/../fonts/glyphicons-halflings-regular.woff2 (original: ../fonts/glyphicons-halflings-regular.woff2)
2015-03-05 16:12:47.718 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Link modified: 77a6e2aa77283c05d58f4ab52102f55684b6fb04/../fonts/glyphicons-halflings-regular.woff (original: ../fonts/glyphicons-halflings-regular.woff)
2015-03-05 16:12:47.719 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Link modified: 77a6e2aa77283c05d58f4ab52102f55684b6fb04/../fonts/glyphicons-halflings-regular.ttf (original: ../fonts/glyphicons-halflings-regular.ttf)
2015-03-05 16:12:47.719 TRACE 11064 --- [nio-8080-exec-2] o.s.w.s.r.CssLinkResourceTransformer     : Link not modified: ../fonts/glyphicons-halflings-regular.svg#glyphicons_halflingsregular

Edit2:如果你注册了RessourceChain -.-,Spring会自动创建一个CssLinkResourceTransformer.请参阅https://github.com/spring-projects/spring-framework/blob/master/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/ResourceChainRegistration.java#L112

Answer 1

Spring 4.1+中的资源处理

您正在使用的VersionStrategy,FixedVersionStrategy,是为处理文件名以加载JavaScript模块的JavaScript模块加载器量身定制的.

由于您使用的是JavaScript模块加载器(require.js),因此使用ContentVersionStrategy进行CSS /图像和使用适用于JS 的FixedVersionStrategy更适合您的应用程序.因此,将配置更改为此应修复它:

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {

    VersionResourceResolver versionResolver = new VersionResourceResolver()
            .addFixedVersionStrategy(version, "/**/*.js")
            .addContentVersionStrategy(version, "/**/*.css", "/**/*.png");

    registry.addResourceHandler("/res/**")
            .addResourceLocations("/resources/")
            .setCachePeriod(CACHE_SECONDS)
            .resourceChain(true)
                .addResolver(versionResolver);
}

请注意,您不需要注册a PathResourceResolver或a CssLinkResourceTransformer,因为它是通过检查您的配置为您完成的(您已经通过阅读源代码了解了这一点).

现在,为了更好地了解该功能,我建议您阅读此博客文章并查看此示例应用程序.

SPR-12669 JIRA问题

实际上,这个问题与你的用例无关,本身并不是一个bug.Guillaume创建了WUIC项目,我们正在讨论如何在Spring项目中更好地集成这个资产管道.因此,作为框架开发人员,他正在为WUIC用户寻求更多灵活性 - 资源处理功能本身正常运行.

您描述的解决方法并非设计用于应用程序,因为您手动执行大量管道工作而没有充分理由,而不是依赖于Spring的默认设置.

另请注意,我们在这里讨论的默认值是由Spring Framework设置的,而不是由Spring Boot设置的.Spring Boot是"仅" 自动配置众所周知的位置来提供静态资源.