Why this change?
There are two problematic queries in question here when loading
notifications in various tabs in the user menu:
```
SELECT "notifications".*
FROM "notifications"
LEFT JOIN topics ON notifications.topic_id = topics.id
WHERE "notifications"."user_id" = 1338 AND (topics.id IS NULL OR topics.deleted_at IS NULL)
ORDER BY notifications.high_priority AND NOT notifications.read DESC,
NOT notifications.read AND notifications.notification_type NOT IN (5,19,25) DESC,
notifications.created_at DESC
LIMIT 30;
```
and
```
EXPLAIN ANALYZE SELECT "notifications".*
FROM "notifications"
LEFT JOIN topics ON notifications.topic_id = topics.id
WHERE "notifications"."user_id" = 1338
AND (topics.id IS NULL OR topics.deleted_at IS NULL)
AND "notifications"."notification_type" IN (5, 19, 25)
ORDER BY notifications.high_priority AND NOT notifications.read DESC, NOT notifications.read DESC, notifications.created_at DESC LIMIT 30;
```
For a particular user, the queries takes about 40ms and 26ms
respectively on one of our production instance where the user has 10K notifications while the site has 600K notifications in total.
What does this change do?
1. Adds the `index_notifications_user_menu_ordering` index to the `notifications` table which is
indexed on `(user_id, (high_priority AND NOT read) DESC, (NOT read)
DESC, created_at DESC)`.
1. Adds a second index `index_notifications_user_menu_ordering_deprioritized_likes` to the `notifications`
table which is indexed on `(user_id, (high_priority AND NOT read) DESC, (NOT read AND notification_type NOT IN (5,19,25)) DESC, created_at DESC)`. Note that we have to hardcode the like typed notifications type here as it is being used in an ordering clause.
With the two indexes above, both queries complete in roughly 0.2ms. While I acknowledge that there will be some overhead in insert,update or delete operations. I believe this trade-off is worth it since viewing notifications in the user menu is something that is at the core of using a Discourse forum so we should optimise this experience as much as possible.
The most common thing that we do with fab! is:
fab!(:thing) { Fabricate(:thing) }
This commit adds a shorthand for this which is just simply:
fab!(:thing)
i.e. If you omit the block, then, by default, you'll get a `Fabricate`d object using the fabricator of the same name.
Right now the experimental user menu sorts notifications the same way that the old menu does: unread high-priority notifications are shown first in reverse-chronological order followed by everything else also in reverse-chronological order. However, since the experimental user menu has dedicated tabs for some notification types and each tab displays a badge with the count of unread notifications in the tab, we feel like it makes sense to change how notifications are sorted in the experimental user menu to this:
1. unread high-priority notifications
2. unread regular notifications
3. all read notifications (both high-priority and regular)
4. within each group, notifications are sorted in reverse-chronological order (i.e. newest is shown first).
This new sorting logic applies to all tabs in the experimental user menu, however it doesn't change anything in the old menu. With this change, if a tab in the experimental user menu shows an unread notification badge for a really old notification, it will be surfaced to the top and prevents confusing scenarios where a user sees an unread notification badge on a tab, but the tab doesn't show the unread notification because it's too old to make it to the list.
Internal topic: t72199.
It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
* REFACTOR: Improve support for consolidating notifications.
Before this commit, we didn't have a single way of consolidating notifications. For notifications like group summaries, we manually removed old ones before creating a new one. On the other hand, we used an after_create callback for likes and group membership requests, which caused unnecessary work, as we need to delete the record we created to replace it with a consolidated one.
We now have all the consolidation rules centralized in a single place: the consolidation planner class. Other parts of the app looking to create a consolidable notification can do so by calling Notification#consolidate_or_save!, instead of the default Notification#create! method.
Finally, we added two more rules: one for re-using existing group summaries and another for deleting duplicated dashboard problems PMs notifications when the user is tracking the moderator's inbox. Setting the threshold to one forces the planner to apply this rule every time.
I plan to add plugin support for adding custom rules in another PR to keep this one relatively small.
* DEV: Introduces a plugin API for consolidating notifications.
This commit removes the `Notification#filter_by_consolidation_data` scope since plugins could have to define their criteria. The Plan class now receives two blocks, one to query for an already consolidated notification, which we'll try to update, and another to query for existing ones to consolidate.
It also receives a consolidation window, which accepts an ActiveSupport::Duration object, and filter notifications created since that value.
Over the years we accrued many spelling mistakes in the code base.
This PR attempts to fix spelling mistakes and typos in all areas of the code that are extremely safe to change
- comments
- test descriptions
- other low risk areas
Introduce the concept of "high priority notifications" which include PM and bookmark reminder notifications. Now bookmark reminder notifications act in the same way as PM notifications (float to top of recent list, show in the green bubble) and most instances of unread_private_messages in the UI have been replaced with unread_high_priority_notifications.
The user email digest is changed to just have a section about unread high priority notifications, the unread PM section has been removed.
A high_priority boolean column has been added to the Notification table and relevant indices added to account for it.
unread_private_messages has been kept on the User model purely for backwards compat, but now just returns unread_high_priority_notifications count so this may cause some inconsistencies in the UI.
Introduces a new site setting `max_notifications_per_user`.
Out-of-the-box this is set to 10,000. If a user exceeds this number of
notifications, we will delete the oldest notifications keeping only 10,000.
To disable this safeguard set the setting to 0.
Enforcement happens weekly.
This is in place to protect the system from pathological states where a
single user has enormous amounts of notifications causing various queries
to time out. In practice nobody looks back more than a few hundred notifications.
This change both speeds up specs (less strings to allocate) and helps catch
cases where methods in Discourse are mutating inputs.
Overall we will be migrating everything to use #frozen_string_literal: true
it will take a while, but this is the first and safest move in this direction
Includes support for flags, reviewable users and queued posts, with REST API
backwards compatibility.
Co-Authored-By: romanrizzi <romanalejandro@gmail.com>
Co-Authored-By: jjaffeux <j.jaffeux@gmail.com>
Rails yanked out observers many many years ago, instead the functionality
was yanked out to a gem that is very lightly maintained.
For example: if we want to upgrade to rails 5 there is no published gem
Internally the usage of observers had quite a few problem.
The series of refactors renamed a bunch of classes to give us more clarity
and removed some magic.
Since rspec-rails 3, the default installation creates two helper files:
* `spec_helper.rb`
* `rails_helper.rb`
`spec_helper.rb` is intended as a way of running specs that do not
require Rails, whereas `rails_helper.rb` loads Rails (as Discourse's
current `spec_helper.rb` does).
For more information:
https://www.relishapp.com/rspec/rspec-rails/docs/upgrade#default-helper-files
In this commit, I've simply replaced all instances of `spec_helper` with
`rails_helper`, and renamed the original `spec_helper.rb`.
This brings the Discourse project closer to the standard usage of RSpec
in a Rails app.
At present, every spec relies on loading Rails, but there are likely
many that don't need to. In a future pull request, I hope to introduce a
separate, minimal `spec_helper.rb` which can be used in tests which
don't rely on Rails.
