Prerender and preload remote video cache.

[gmajoulet]

Prerender and preload remote video cache.

Additional information:
The XHR request marked as prerenderSafe goes to domain-com.cdn.ampproject.org/**.
The video sources that preload are loaded from the exact same system as the existing video cache that preloads today.

[amp-owners-bot]

Hey @ampproject/wg-caching! These files were changed:

validator/testdata/transformed_feature_tests/amp-video-cached-source.html
validator/testdata/transformed_feature_tests/amp-video-cached-source.out

[gmajoulet]

Added transformed AMP validation tests to ensure i-amphtml-video-cached-source is not a valid attr.

PTAL

[honeybadgerdontcare]

Added transformed AMP validation tests to ensure i-amphtml-video-cached-source is not a valid attr.

PTAL

Note this isn't a transformed AMP test, but a regular AMP test. Should it be valid for transformed AMP?

Those test cases are under validator/testdata/transformed_feature_tests

[honeybadgerdontcare]

LGTM for regular AMP test, but probably should add a transformed AMP test as well.

[gmajoulet]

It should be invalid for both regular and transformed AMP. Should I simply move the files to this folder? I transformed the HTML using the AMP optimizer.

[honeybadgerdontcare]

It should be invalid for both regular and transformed AMP.

This isn't something that the optimizer or AMP caches should do then.

Should I simply move the files to this folder? I transformed the HTML using the AMP optimizer.

Yes and no. Yes they should be in that folder but only copy over the parts specific to this change...

...I'd prefer not to use the optimizer output for these tests. I'd rather they be very targeted to their testing purpose. Normally I'd say use the minimum valid one but that includes the full CSS. An easy one to start off of would be the nonce one (removing the nonce of course) and making it explicit to the test criteria here.

[gmajoulet]

The goal of this test is to ensure that i-amphtml-video-cached-source is invalid for both normal and transformed, as making it valid would allow an attacker to break privacy preserving prerendering. So removing the CSS etc sounds good, I'll update the test

[honeybadgerdontcare]

The goal of this test is to ensure that i-amphtml-video-cached-source is invalid for both normal and transformed, as making it valid would allow an attacker to break privacy preserving prerendering. So removing the CSS etc sounds good, I'll update the test

Great, thank you. Please also move it to the feature tests directory for transformed AMP (testdata/transformed_feature_tests/)

[honeybadgerdontcare]

ty