wg-caching status update 2020-05-06

[Gregable]

What was accomplished?

• Signed Exchanges:
  • AMP Packager can now be deployed on Google Cloud. Instructions
  • AMP Packager now supports docker multi-stage builds reducing the image sizes by 99%. #402
  • Various bugfixes to NGINX Signed Exchange Module.
• Google AMP Cache relevant updates:
  • New origin mapping (0-example-com-0) live. #26205
  • Limited the maximum generated image srcset to 820px in the Cache to improve LCP.
  • Experiment running to have the AMP cache prefetch a heuristically determined hero image, similar to what the AMP packager does for AMP SXG documents.
  • DOM Purify investigation, mentioned at last update, resulted in no planned cache changes.
• Major revamp of the AMP CSS validation engine. This was designed to support a request to have a increasingly divergent CSS specification for the AMP Email specification. Some of the addressed issues on Github include #27507, #27239, and #12651. We now support independednt per-format css properties, vendor-prefixes, byte lengths, and URL validation.
• Progress towards open sourcing the C++ AMPHTML Validator, but work remains ongoing.
• Design agreed on with OpenJS Foundation for disentangling the AMP Runtime from Google's Cache domains. #13

What's next?

• Bring the Web Packager towards feature parity with the AMP Packager to further support building non-AMP Signed Exchanges. For example, adding support for ACME cert renewal.
• Complete the C++ Validator Open-Sourcing.
• Add a prometheus endpoint to the AMP Packer for the next release. #357
• Investigating Google Cloud Click-to-deploy marketplace inclusion for the AMP Packager.
• Wrap up the Google AMP Cache hero image experiment mentioned above.