Package org.springframework.web.servlet.resource

Class VersionResourceResolver

java.lang.Object
org.springframework.web.servlet.resource.AbstractResourceResolver
org.springframework.web.servlet.resource.VersionResourceResolver
All Implemented Interfaces:
ResourceResolver
public class VersionResourceResolver extends AbstractResourceResolver
Resolves request paths containing a version string that can be used as part of an HTTP caching strategy in which a resource is cached with a date in the distant future (e.g. 1 year) and cached until the version, and therefore the URL, is changed.

Different versioning strategies exist, and this resolver must be configured with one or more such strategies along with path mappings to indicate which strategy applies to which resources.

ContentVersionStrategy is a good default choice except in cases where it cannot be used. Most notably the ContentVersionStrategy cannot be combined with JavaScript module loaders. For such cases the FixedVersionStrategy is a better choice.

Note that using this resolver to serve CSS files means that the CssLinkResourceTransformer should also be used in order to modify links within CSS files to also contain the appropriate versions generated by this resolver.

Since:
4.1
Author:
Brian Clozel, Rossen Stoyanchev
See Also:

  • Constructor Details

    • VersionResourceResolver

      public VersionResourceResolver()

  • Method Details

    • setStrategyMap

      public void setStrategyMap(Map<String,VersionStrategy> map)
      Set a Map with URL paths as keys and VersionStrategy as values.

      Supports direct URL matches and Ant-style pattern matches. For syntax details, see the AntPathMatcher javadoc.

      Parameters:
      map - a map with URLs as keys and version strategies as values

    • getStrategyMap

      public Map<String,VersionStrategy> getStrategyMap()
      Return the map with version strategies keyed by path pattern.

    • addContentVersionStrategy

      public VersionResourceResolver addContentVersionStrategy(String... pathPatterns)
      Insert a content-based version in resource URLs that match the given path patterns. The version is computed from the content of the file, e.g. "css/main-e36d2e05253c6c7085a91522ce43a0b4.css". This is a good default strategy to use except when it cannot be, for example when using JavaScript module loaders, use addFixedVersionStrategy(java.lang.String, java.lang.String...) instead for serving JavaScript files.
      Parameters:
      pathPatterns - one or more resource URL path patterns, relative to the pattern configured with the resource handler
      Returns:
      the current instance for chained method invocation
      See Also:

    • addFixedVersionStrategy

      public VersionResourceResolver addFixedVersionStrategy(String version, String... pathPatterns)
      Insert a fixed, prefix-based version in resource URLs that match the given path patterns, for example: "{version}/js/main.js". This is useful (vs. content-based versions) when using JavaScript module loaders.

      The version may be a random number, the current date, or a value fetched from a git commit sha, a property file, or environment variable and set with SpEL expressions in the configuration (e.g. see @Value in Java config).

      If not done already, variants of the given pathPatterns, prefixed with the version will be also configured. For example, adding a "/js/**" path pattern will also configure automatically a "/v1.0.0/js/**" with "v1.0.0" the version String given as an argument.

      Parameters:
      version - a version string
      pathPatterns - one or more resource URL path patterns, relative to the pattern configured with the resource handler
      Returns:
      the current instance for chained method invocation
      See Also:

    • addVersionStrategy

      public VersionResourceResolver addVersionStrategy(VersionStrategy strategy, String... pathPatterns)
      Register a custom VersionStrategy to apply to resource URLs that match the given path patterns.
      Parameters:
      strategy - the custom strategy
      pathPatterns - one or more resource URL path patterns, relative to the pattern configured with the resource handler
      Returns:
      the current instance for chained method invocation
      See Also:

    • resolveResourceInternal

      @Nullable protected Resource resolveResourceInternal(@Nullable HttpServletRequest request, String requestPath, List<? extends Resource> locations, ResourceResolverChain chain)
      Specified by:
      resolveResourceInternal in class AbstractResourceResolver

    • resolveUrlPathInternal

      @Nullable protected String resolveUrlPathInternal(String resourceUrlPath, List<? extends Resource> locations, ResourceResolverChain chain)
      Specified by:
      resolveUrlPathInternal in class AbstractResourceResolver

    • getStrategyForPath

      @Nullable protected VersionStrategy getStrategyForPath(String requestPath)
      Find a VersionStrategy for the request path of the requested resource.
      Returns:
      an instance of a VersionStrategy or null if none matches that request path