Video upload isn't working like expected

[marecar3]

Describe the bug

1. When I try to upload an mp4 video using Premium account, It's with success in 30% of attempts and in a case of failure, I am getting random errors :

• Stuck on "converting 99% "
• Stuck on "Loading..."
• Stuck on "Conversion error"
• Stuck on "converting 52%"

2. When it's a success I can't preview uploaded video

To reproduce
Steps to reproduce the behavior:

1. Download video from https://sample-videos.com/video123/mp4/720/big_buck_bunny_720p_1mb.mp4
2. Create a new Gutenberg (Block Editor) Post
3. Add video block
4. Select Upload and pick a downloaded video from step 1.

Expected behavior
Sometimes it's stuck with uploading, sometimes it's working

Screenshots

Desktop (please complete the following information):

• OS Mac OS Mojave : 10.14.3
• Browser Chrome
• Version 73.0.3683.86 (Official Build) (64-bit)

[cecoates]

I had a similar issue today.

#14530001-hc

This error was a bit less helpful, "unknown error". The Learn More link just redirects to the Videopress website.

That error shows when using the video block AND in the media library.

The video itself seems fine, and if you copy the video URL into a paragraph block it embeds as expected.

[nagpai]

Noticed this on #14691764-hc

[kwight]

This seems to be caused by some sort of polling to https://io.videopress.com/socket.io/?guid=<guid>&... that never resolves; they just continue endlessly (which presumably means that some UI check never completes, leaving the preview in an unresolved state).

The VideoPress preview is also an iframe within an iframe within the Video block; that can't be good.

[mmtr]

I noted an interesting pattern. Every time the previews gets stuck in the loading state, requests to https://public-api.wordpress.com/rest/v1/videos/<guid>?http_envelope=1 return valueless width/height:

However, working previews get proper values:

I think this is related to some kind of race condition and it's depending on the speed of the transcoder job (sometimes data is retrieved when the transcoder already set the dimensions, sometimes it is retrieved too early).

[mmtr]

Just confirmed the issue is coming from the VideoPress JS library. The player gets stuck because it is not refetching the data when the video is processing, although it should do it according to https://github.com/Automattic/videopress/blob/ff199f65feff54db19799005237b11687e3b9385/lib/watch.js#L28. Will keep investigating.

[mmtr]

It ended up being a problem of the video-wp-com theme in WP.com. That theme is setting a custom request provider that is executed only once because it is hooked into the window's load event. I'm preparing a diff refactoring that function to see if that solves this issue.

[mmtr]

Fix undergoing in D34084-code.

[kwight]

The first part of this bug is now fixed by @mmtr in D34084-code: uploads complete predictably and consistently 🎉

When it's a success I can't preview uploaded video

This part remains; I'm closing this issue and we'll use #36836 to track the inactive UI.