Stop pinning amp-carousel at v0.1 so that v0.2 can be used

[westonruter]

This is a follow-up to #3084.

It turns out that amp-carousel 0.2 wasn't broken due to a dependence on amp-base-carousel, but there was some other issue: ampproject/amphtml#23966. So we can allow amp-carousel to update from 0.1 to 0.2 once the AMP fix is live.

Fixes #3700.

[nainar]

Would wait on us moving all carousels in amp.dev and manually confirming that before merging this to be safe

[westonruter]

@nainar Any update on this?

I'm looking at https://amp.dev/documentation/examples/components/amp-carousel/ and I'm still seeing v0.1:

<script custom-element="amp-carousel" src="https://cdn.ampproject.org/v0/amp-carousel-0.1.js" async=""></script>

[westonruter]

@kienstra I think this is ready for review now, and that we should merge it for the 1.5 release and so that we can test it in develop. Would you check to make sure it works properly with the improvements you've been making on the galleries?

[westonruter]

And actually, Naina says it's ready to go, so once we've tested we'll make it part of v1.4.1.

[kienstra]

Question About Right Arrow In v0.2

Hi @nainar,
Could you please help with a question about the right arrow appearing with the amp-carousel v0.2 script?

Maybe this isn't an issue with AMP HTML, and there's some styling we could apply to prevent this.

Here's a CodePen of it. On changing amp-carousel-0.2.js back to amp-carousel-0.1.js in that CodePen, the issue doesn't appear anymore.

Steps to reproduce in WordPress

1. Checkout this PR's branch, and activate Twenty Nineteen
2. Create a new post
3. Add a Gallery block
4. Add only one image to it, like this
5. Select 'Display as carousel'
6. Click 'Preview,' and go to the AMP URL
7. Expected: Because there's only 1 image in the carousel, there shouldn't be a right arrow
8. Actual: There's a right arrow, but clicking it doesn't do anything:

9. Create another Gallery block, but with at least 2 images
10. Select 'Display as carousel'
11. Click 'Preview,' and go to the AMP URL
12. Expected: When the last slide in the carousel displays, the right arrow shouldn't be visible
13. Actual: It's still visible:

This isn't a common issue, and I didn't see it with most Core themes. Maybe there's some styling that Twenty Nineteen has that's associated with this issue.

[kienstra]

Actually, I should probably make the comment above into an issue for amphtml.

[westonruter]

@kienstra I'm not seeing the same thing. For the first carousel, I see no arrow:

And in the second I see no next arrow:

[kienstra]

Approved

Hi @westonruter,
Since you couldn't reproduce this issue on the CodePen, this should be ready to merge.

[schlessera]

I could replicate the issue: ampproject/amphtml#25510 (comment)

[kienstra]

@schlessera, thanks for testing this. I reopened the amphtml issue.

[westonruter]

Upstream fix has been merged: ampproject/amphtml#25549

So we can merge this PR when that AMP update has been deployed, unless we're happy to live with some flaky buttons in develop.

[kienstra]

Sounds good!

[westonruter]

The fix was released a couple days ago in https://github.com/ampproject/amphtml/releases/tag/1911191835190

[csossi]

verified in qa

[archon810]

@westonruter Sorry to revive a necro post, but we're still seeing 0.1 load instead of 0.2. What could be the cause?

For example: https://www.androidpolice.com/2020/07/27/quick-charge-5-promises-to-charge-phones-from-0-to-100-in-just-15-minutes/?amp

[westonruter]

@archon810 The issue is that amp-carousel 0.1 is being loaded by https://cdn.ampproject.org/v0/amp-lightbox-gallery-0.1.js, since v0.1 is still the latest version. Are you perhaps trying to work around ampproject/amphtml#35402?

[maciejmackowiak]

@westonruter in the above post where the bug occurs we are just using lightbox gallery by adding lightbox="lightbox" to the amp-img
We don't have any work around there.

[westonruter]

@maciejmackowiak ok, but are you trying to fix a problem? Or are you just wondering why a different version is showing up versus what is expected?

[archon810]

@westonruter From what I understand, we're trying to resolve the bugs that are associated with 0.1 and should be fixed in 0.2.

Specifically

• https://github.com/android-police/androidpolice-public/issues/100
• Bug in Amp Lightbox Gallery where it skips an image amphtml#21559
• amp-lightbox-gallery: issue when only 2 images amphtml#22608

Judging by the fact that all of these were verified and closed before, 0.2 was live, but was then reverted back to 0.1 somehow?

[westonruter]

@archon810 No, the issue is that amp-lightbox-gallery will lazy-load the amp-carousel script at the moment that the lightbox functionality is invoked. When you aren't using an amp-carousel on the page, then the AMP plugin doesn't add the v0.2 script to the page up-front. Since v0.2 is not the “latest” version, the means that the amp-lightbox-gallery will lazy-load v0.1 instead.

If you try adding a Gallery to a post and enable the carousel toggle in AMP Settings, then you'll see that the amp-carousel v0.2 script is added to the page initially, and when opening a lightbox it doesn't then try to lazy-load v0.1.

So, as a workaround to this I've opened #6509 which will allow you to manually wp_enqueue_script('amp-carousel') which will cause the v0.2 version to be added to the page, and then when post-processing runs it won't get stripped out when there is no amp-carousel but there is an amp-lightbox-gallery.

[archon810]

@maciejmackowiak Please take note and implement the fix when the relevant AMP release is out.

[westonruter]

@maciejmackowiak @archon810 The PR has been merged and cherry-picked into the 2.1 branch. So you can test with the latest 2.1.x build.