Enhance ResourceHttpRequestHandler with ResourceTransformer strategy [SPR-11800]

[spring-projects-issues]

Brian Clozel opened SPR-11800 and commented

In order to complete the ResourceResolver strategy, a ResourceTransformer one is needed.
The main use case for this strategy is resources that link to other resources from their content - links to other resources need to be updated to apply Resolver strategies.

For example: a CSS file that link to images (to use them as background) or other CSS files needs to have its inner links updated by resolvers to match the configured strategy.

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Sub-tasks:

• Improve CssLinkResourceTransformer to only update links to relative resources [SPR-11860] #16479 Improve CssLinkResourceTransformer to only update links to relative resources

Issue Links:

• Support Content-based Hash Fingerprinted URLs in ResourceHttpRequestHandler [SPR-10310] #14944 Support Content-based Hash Fingerprinted URLs in ResourceHttpRequestHandler ("is depended on by")
• Improve CssLinkResourceTransformer to only update links to relative resources [SPR-11860] #16479 Improve CssLinkResourceTransformer to only update links to relative resources

Referenced from: commits 6966e89