1536102 - Add encryption scheme to MediaKeySystemMediaCapability to enable apps to discover scheme support

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, enhancement, P2)

Description

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

The changes involved are detailed in this proposal, as well as much of the motivation.

Of note, but not in the scope of this bug: a similar proposal for media capabilities is discussed here.

Comment 1

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Created https://github.com/WICG/encrypted-media-encryption-scheme/pull/12 in response to concerns about enum usage for encryption scheme. Please see the PR and issues linked within for further details.

Comment 2

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=345d7fdf7458be5c0215b11c639954aac704b11b

Comment 3

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=deab2d2edd0da63a3a9de39ab20be5340caf2d55

Comment 4

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: Bug 1536102 - P1: Add pref to gate encryption scheme check functionality behind. r?cpearce

First step in implementing behaviour proposed in
https://github.com/WICG/encrypted-media-encryption-scheme/blob/master/explainer.md

Comment 5

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: Bug 1536102 - P2: Add encryption scheme to MediaKeySystemMediaCapability dictionary. r?smaug

Add encryption scheme member to MediaKeySystemMediaCapability dict, but hide it
behind a pref as the behaviour involved is only proposed at this stage.

Depends on D34300

Comment 6

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: Bug 1536102 - P3: Implement filtering behaviour for encryption scheme if passed on MediaKeySystemMediaCapability. r?cpearce

Depends on D34301

Comment 7

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: Bug 1536102 - P4: Enabled WPT for encrypted media scheme checking. r?cpearce

Enable the web platform tests for clearkey scheme checking. Since these tests
simply check if the functionality is implemented, and do not check if the
browsers actually support different encryption schemes, it's okay to do this
even though we don't have cbcs support in clearkey yet. I.e. it's enough that a
page can ask "do you support cbcs in clearkey?" to Firefox to pass the test, the
answer from Firefox doesn't have to be "yes."

Add the pref setting to the DRM scheme checking test, though leave the
expectations as they are on this test, as in automation the test will still not
pass due to Widevine downloads being blocked. My hope is that we can find a
solution to this Widevine download issue in automation, at which point we'd
expect that tests to start passing due to the pref added in this patch -- at
which point we could toggle the expectations.

Depends on D34302

Comment 8

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

My current work on this uses a DOMString for the encryption scheme rather than an enum for the reasons detailed in https://github.com/WICG/encrypted-media-encryption-scheme/pull/12 I'm planning on discussing further on GitHub why I think a DOMString is preferred in the coming week.

Comment 9

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=1efa8ac0a0cce5c1ced1cf5acbc94b4855cbf7b6

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/be993cc8f451
P1: Add pref to gate encryption scheme check functionality behind. r=cpearce
https://hg.mozilla.org/integration/autoland/rev/7c7382012e4e
P2: Add encryption scheme to MediaKeySystemMediaCapability dictionary. r=smaug
https://hg.mozilla.org/integration/autoland/rev/70b2674c95c5
P3: Implement filtering behaviour for encryption scheme if passed on MediaKeySystemMediaCapability. r=cpearce
https://hg.mozilla.org/integration/autoland/rev/7cf9846578e4
P4: Enabled WPT for encrypted media scheme checking. r=cpearce

Comment 11

[Dorel Luca [:dluca]]

https://hg.mozilla.org/mozilla-central/rev/be993cc8f451
https://hg.mozilla.org/mozilla-central/rev/7c7382012e4e
https://hg.mozilla.org/mozilla-central/rev/70b2674c95c5
https://hg.mozilla.org/mozilla-central/rev/7cf9846578e4

Comment 12

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

I've created a test page to help with testing this functionality in browsers. The readme details how to toggle to feature on in Firefox and Chrome.