Reader: poll for changes in the comment list

[designsimply]

We should poll for changes in the comment list to show new comments.

Steps to reproduce:

1. Go to https://wordpress.com/ and click on one of your blog posts to open it in a single-post view
2. In a separate browser window, add and approve a new comment on the post
3. Watch to see if the comment shows up

Result: new comments don't show up automatically when you are viewing a single post in the Reader and a new comment comes in.

[alisterscott]

Confirmed this behaviour has not changed - comments do not dynamically update in the Reader

[bluefuton]

I started some of the plumbing for this in #26318 but it's not exposed on the UI yet. @westi suggested we use Pinghub rather than polling in the background.

[bluefuton]

Just noting that @hewsut's #40396 adds real-time comments to Reader full post.

[github-actions]

This issue is stale because it has been 180 days with no activity. You can keep the issue open by adding a comment. If you do, please provide additional context and explain why you’d like it to remain open. You can also close the issue yourself — if you do, please add a brief explanation and apply one of relevant issue close labels.

[bluefuton]

This should have been fixed by #40396 but that will need to be confirmed (cc @worldomonation)

[worldomonation]

I checked this behavior across multiple browsers and both Atomic and Simple.

I was not able to observe the real time comment fetching in a full page post.

Steps I took:

1. log in as User A.
2. open the post under test.
3. as user A, in a separate tab open the Comments management section by going to My Sites > Site > Comments.
4. as an unlogged in user, enter some comment on the post under test.
5. as User A, refresh the tab used in Step 3.
6. as User A, approve the comment.
7. as User A, switch back to the the post under test.

The steps above were not able to demonstrate real-time comment loading when viewing a single post on both Atomic and Simple sites.

On Browser: Firefox Nightly 87.0a1 with Developer Tools > Network open, I was not able to observe any network requests being made.

Video demonstrating on an Atomic site:

Screen.Recording.2021-02-16.at.10.23.16.AM.mov

[github-actions]

This issue is stale because it has been 180 days with no activity. You can keep the issue open by adding a comment. If you do, please provide additional context and explain why you’d like it to remain open. You can also close the issue yourself — if you do, please add a brief explanation and apply one of relevant issue close labels.

[davemart-in]

Gonna close this one for now. Happy to re-open if additional customers report it or if someone wants to work on it.