Defer Diff Loading on Changes Tab

[ncounter]

Applying the common pattern: load the static/text part of the page within the main page request, send an async call right after the page load to fetch the heavy content of the page while a loading message is visible.

Test

Visit https://obs-reviewlab.opensuse.org/ncounter-async-loading-changes/request/show/1/changes

Before: the page is loaded fully sync - spot the loading icon at the top of the browser tab

After: the page is quickly loaded in the header and the rest but the content, that starts loading async

[obs-bot]

Review app will appear here: http://obs-reviewlab.opensuse.org/ncounter-async-loading-changes

[krauselukas]

@ncounter we should stick to the bs_request number here. id != number. Usually its the same, but its still two different things, and could lead to problems if we exchange them.

[krauselukas]

ah its just the naming, you are using the number. but we should stay consistent with the naming here

[ncounter]

Exactly, it's only a variable name to the loop to keep the queryString parameter alive. The parameter is populated in set_diff_to_superseded_id.

I'm going to rename it. Thinking about it: before it was diff_to_superseded, now it is diff_to_superseded_id, I'm going for diff_to_superseded_number but I also wonder if I could get rid of the diff_to prefix and finalize it to superseded_number only 🤔 The fact that we use it for the diff is a detail, we could use it for something else too. What do you think?

[krauselukas]

yeah its confusing, diff_to_superseded doesnt contain any diff. Its simply the superseding request object. I would also just call it this way. Maybe simply superseding_request and superseding_request_number.

[ncounter]

As discussed and decided offline, the renaming change will happen in a separate PR due to the fact the changes involves much more than the scope of this PR.

#15906