restructure query so it avoids ORs
It appears postgres is picking suboptimal indexes if too many ORs exist
despite how trivial the condition is.
This bypasses conditional in the query and evals them upfront.
On meta for my user this made a 10x perf difference.
This boils down to either having `OR u.admin` or not having `OR u.admin` in
the query.
Note, to avoid race conditions we are setting last_unread to 10 minutes ago
if there is nothing unread.
This is safer in case of in progress transactions
we don't want to lose unread for any window of time.
This optimisation avoids large scans joining the topics table with the
topic_users table.
Previously when a user carried a lot of read state we would have to join
the entire read state with the topics table. This operation would slow down
home page and every topic page. The more read state you accumulated the
larger the impact.
The optimisation helps people who clean up unread, however if you carry
unread from years ago it will only have minimal impact.
Sometimes sidekiq is so fast that it starts jobs before transactions
have comitted. This patch moves the message bus stuff until after things
have comitted.
"Rejecting" a user in the queue is equivalent to deleting them, which
would then making it impossible to review rejected users. Now we store
information about the user in the payload so if they are deleted things
still display in the Rejected view.
Secondly, if a user is destroyed outside of the review queue, it will
now automatically "Reject" that queue item.
Conversely, if a user is deactivated the reviewable should automatically
be rejected.
Before this fix, if a user was not active they'd still show in the
review queue but without an "Approve" button which was confusing.
Previously every rebake would remove and recreate records in this table
This caused created_at and updated_at to keep changing
Yes, I know the SQL is somewhat complex, but this makes quote extraction
more efficient cause we do everything in 2 round trips.
This also removes some concurrency protection we should no longer need
Some sites have external URLs that don't even match `%/uploads/%' and
some sites surprise me with URLs that contains the default path when it
is a site in a multisite cluster. We can't do anything about those.
Adds the parallel_tests gem, and redis/postgres configuration for running rspec tests in parallel. To use:
```
rake parallel:rake[db:create]
rake parallel:rake[db:migrate]
rake parallel:spec
```
This brings the test suite from 12m20s to 3m11s on my macOS machine
This commit fixes the follow quality issue with `PostSearchData#raw_data`:
1. URLs are being tokenized and links with similar href and characters
are being duplicated in the raw data.
`Post#cooked`:
```
<p><a href=\"https://meta.discourse.org/some.png\" class=\"onebox\" target=\"_blank\" rel=\"nofollow noopener\">https://meta.discourse.org/some.png</a></p>
```
`PostSearchData#raw_data` Before:
```
This is a test topic 0 Uncategorized https://meta.discourse.org/some.png discourse org/some png https://meta.discourse.org/some.png discourse org/some png
```
`PostSearchData#raw_data` After:
```
This is a test topic 0 Uncategorized https://meta.discourse.org/some.png meta discourse org
```
2. Ligthbox being included in search pollutes the
`PostSearchData#raw_data` unncessarily.
From 28 March 2018 to 28 March 2019, searches for the term `image` on
`meta.discourse.org` had a click through rate of 2.1%. Non-lightboxed images are not included in indexing for search yet we were indexing content within a lightbox. Also, search for terms like `image` was affected we were using `Pasted image` as the filename for
uploads that were pasted.
`Post#cooked`
```
<p>Let me see how I can fix this image<br>\n<div class=\"lightbox-wrapper\"><a class=\"lightbox\" href=\"https://meta.discourse.org/some.png\" title=\"some.png\" rel=\"nofollow noopener\"><img src=\"https://meta.discourse.org/some.png\" width=\"275\" height=\"299\"><div class=\"meta\">\n<svg class=\"fa d-icon d-icon-far-image svg-icon\" aria-hidden=\"true\"><use xlink:href=\"#far-image\"></use></svg><span class=\"filename\">some.png</span><span class=\"informations\">1750×2000</span><svg class=\"fa d-icon d-icon-discourse-expand svg-icon\" aria-hidden=\"true\"><use xlink:href=\"#discourse-expand\"></use></svg>\n</div></a></div></p>
```
`PostSearchData#raw_data` Before:
```
This is a test topic 0 Uncategorized Let me see how I can fix this image some.png png https://meta.discourse.org/some.png discourse org/some png some.png png 1750×2000
```
`PostSearchData#raw_data` After:
```
This is a test topic 0 Uncategorized Let me see how I can fix this image
```
In terms of indexing performance, we now have to parse the given HTML
through nokogiri twice. However performance is not a huge worry here since a string length of 194170 takes only 30ms
to scrub plus the indexing takes place in a background job.
