I merged this PR in yesterday, finally thinking this was done https://github.com/discourse/discourse/pull/12958 but then a wild performance regression occurred. These are the problem methods:
1aa20bd681/app/serializers/topic_tracking_state_serializer.rb (L13-L21)
Turns out date comparison is super expensive on the backend _as well as_ the frontend.
The fix was to just move the `treat_as_new_topic_start_date` into the SQL query rather than using the slower `UserOption#treat_as_new_topic_start_date` method in ruby. After this change, 1% of the total time is spent with the `created_in_new_period` comparison instead of ~20%.
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History:
Original PR which had to be reverted **https://github.com/discourse/discourse/pull/12555**. See the description there for what this PR is achieving, plus below.
The issue with the original PR is addressed in 92ef54f402
If you went to the `x unread` link for a tag Chrome would freeze up and possibly crash, or eventually unfreeze after nearly 10 mins. Other routes for unread/new were similarly slow. From profiling the issue was the `sync` function of `topic-tracking-state.js`, which calls down to `isNew` which in turn calls `moment`, a change I had made in the PR above. The time it takes locally with ~1400 topics in the tracking state is 2.3 seconds.
To solve this issue, I have moved these calculations for "created in new period" and "unread not too old" into the tracking state serializer.
When I was looking at the profiler I also noticed this issue which was just compounding the problem. Every time we modify topic tracking state we recalculate the sidebar tracking/everything/tag counts. However this calls `forEachTracked` and `countTags` which can be quite expensive as they go through the whole tracking state (and were also calling the removed moment functions).
I added some logs and this was being called 30 times when navigating to a new /unread route because `sync` is being called from `build-topic-route` (one for each topic loaded due to pagination). So I just added a debounce here and it makes things even faster.
Finally, I changed topic tracking state to use a Map so our counts of the state keys is faster (Maps have .size whereas objects you have to do Object.keys(obj) which is O(n).)
<!-- NOTE: All pull requests should have tests (rspec in Ruby, qunit in JavaScript). If your code does not include test coverage, please include an explanation of why it was omitted. -->
Original PR which had to be reverted **https://github.com/discourse/discourse/pull/12555**. See the description there for what this PR is achieving, plus below.
The issue with the original PR is addressed in 92ef54f402
If you went to the `x unread` link for a tag Chrome would freeze up and possibly crash, or eventually unfreeze after nearly 10 mins. Other routes for unread/new were similarly slow. From profiling the issue was the `sync` function of `topic-tracking-state.js`, which calls down to `isNew` which in turn calls `moment`, a change I had made in the PR above. The time it takes locally with ~1400 topics in the tracking state is 2.3 seconds.
To solve this issue, I have moved these calculations for "created in new period" and "unread not too old" into the tracking state serializer.
When I was looking at the profiler I also noticed this issue which was just compounding the problem. Every time we modify topic tracking state we recalculate the sidebar tracking/everything/tag counts. However this calls `forEachTracked` and `countTags` which can be quite expensive as they go through the whole tracking state (and were also calling the removed moment functions).
I added some logs and this was being called 30 times when navigating to a new /unread route because `sync` is being called from `build-topic-route` (one for each topic loaded due to pagination). So I just added a debounce here and it makes things even faster.
Finally, I changed topic tracking state to use a Map so our counts of the state keys is faster (Maps have .size whereas objects you have to do Object.keys(obj) which is O(n).)
The aim of this PR is to improve the topic tracking state JavaScript code and test coverage so further modifications can be made in plugins and in core. This is focused on making topic tracking state changes easier to respond to with callbacks, and changing it so all state modifications go through a single method instead of modifying `this.state` all over the place. I have also tried to improve documentation, make the code clearer and easier to follow, and make it clear what are public and private methods.
The changes I have made here should not break backwards compatibility, though there is no way to tell for sure if other plugin/theme authors are using tracking state methods that are essentially private methods. Any name changes made in the tracking-state.js code have been reflected in core.
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We now have a `_trackedTopicLimit` in the tracking state. Previously, if a topic was neither new nor unread it was removed from the tracking state; now it is only removed if we are tracking more than `_trackedTopicLimit` topics (which is set to 4000). This is so plugins/themes adding topics with `TopicTrackingState.register_refine_method` can add topics to track that aren't necessarily new or unread, e.g. for totals counts.
Anywhere where we were doing `tracker.states["t" + data.topic_id] = newObject` has now been changed to flow through central `modifyState` and `modifyStateProp` methods. This is so state objects are not modified until they need to be (e.g. sometimes properties are set based on certain conditions) and also so we can run callback functions when the state is modified.
I added `onStateChange` and `onMessageIncrement` methods to register callbacks that are called when the state is changed and when the message count is incremented, respectively. This was done so we no longer need to do things like `@observes("trackingState.states")` in other Ember classes.
I split up giant functions like `sync` and `establishChannels` into smaller functions for readability and testability, and renamed many small functions to _functionName to designate them as private functions which not be called by consumers of `topicTrackingState`. Public functions are now all documented (well...at least ones that are not immediately obvious).
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On the backend side, I have changed the MessageBus publish events for TopicTrackingState to send back tags and tag IDs for more channels, and done some extra code cleanup and refactoring. Plugins may override `TopicTrackingState.report` so I have made its footprint as small as possible and externalised the main parts of it into other methods.
This is a try to simplify logic around dismiss new topics to have one solution to work in all places - dismiss all-new, dismiss new in a specific category or even in a specific tag.
Disabling shared drafts used to leave topics in an inconsistent state
where they were not displayed as shared drafts and thus there was no
way of publishing them. Moreover, they were accessible just to users
who have permissions to create shared drafts.
This commit adds another permission check that is used for most
operations and the old can_create_shared_draft? remains used just when
creating a new shared draft.
This is an edge-case of 9fb3629. An admin could set the shared draft category to one where both TL2 and TL3 users have access but only give shared draft access to TL3 users. If something like this happens, we need to make sure that TL2 users won't be able to see them, and they won't be listed on latest.
Before this change, `SharedDrafts` were lazily created when a destination category was selected. We now create it alongside the topic and set the destination to the same shared draft category.
Previously thumbnails were only preloaded for queries using `TopicQuery#default_results`, which meant that requests for PM topic lists would lead to N+1 queries.
This commit moves the preloading into TopicList#load_topics, along with other similar preloads (e.g. plugin custom fields)
The direct call to `ActiveRecord::Associations::Preloader#preload` is necessary because `@topics` can be an array, not an `ActiveRecord::Relation`
When that site setting is enabled, the category counts (new/unread)
include the subcategory definition topics, but the topics aren't included
in the list. This fixes that discrepancy.
This is intended for use by plugins which are building their own topic lists, and want to include PMs alongside regular topics (e.g. discourse-assign). It does not get used directly in core.
Like "default watching" and "default tracking" categories option now the "regular" categories support is added. It will be useful for sites that are muted by default. The user option will be displayed only if `mute_all_categories_by_default` site setting is enabled.
This stops sync of tracking state when list is filtered, in the past this
would cause the tracking state to go off wack.
Additionally this introduces an alias for "filter=tracking", called "f=tracking"
This was done cause the term "filter" is used internally in 2 different ways
the main way is for /unread /new filtering.
Trying to also call a query param "filter" causes enormous amounts of
internal pain, this circumvents the issue.
This adds a special filter to topic lists that will filter to tracked and
watched categories.
To use it you can visit:
`https://sitename/?filter=tracked`
`https://sitename/unread?filter=tracked`
and so on
Note, we do not include explicitly tracked and watched topics **outside** of
the tracked categories and tags.
We can consider a `filter=all_tracked` to cover this edge case.
Before this change:
- first full page load would get category defaults defined un cateory settings
- a navigation to a topic and then back to categories list would reset defaut to the ones defined in discovery/topics
This introduces new APIs for obtaining optimized thumbnails for topics. There are a few building blocks required for this:
- Introduces new `image_upload_id` columns on the `posts` and `topics` table. This replaces the old `image_url` column, which means that thumbnails are now restricted to uploads. Hotlinked thumbnails are no longer possible. In normal use (with pull_hotlinked_images enabled), this has no noticeable impact
- A migration attempts to match existing urls to upload records. If a match cannot be found then the posts will be queued for rebake
- Optimized thumbnails are generated during post_process_cooked. If thumbnails are missing when serializing a topic list, then a sidekiq job is queued
- Topic lists and topics now include a `thumbnails` key, which includes all the available images:
```
"thumbnails": [
{
"max_width": null,
"max_height": null,
"url": "//example.com/original-image.png",
"width": 1380,
"height": 1840
},
{
"max_width": 1024,
"max_height": 1024,
"url": "//example.com/optimized-image.png",
"width": 768,
"height": 1024
}
]
```
- Themes can request additional thumbnail sizes by using a modifier in their `about.json` file:
```
"modifiers": {
"topic_thumbnail_sizes": [
[200, 200],
[800, 800]
],
...
```
Remember that these are generated asynchronously, so your theme should include logic to fallback to other available thumbnails if your requested size has not yet been generated
- Two new raw plugin outlets are introduced, to improve the customisability of the topic list. `topic-list-before-columns` and `topic-list-before-link`
We have the `# frozen_string_literal: true` comment on all our
files. This means all string literals are frozen. There is no need
to call #freeze on any literals.
For files with `# frozen_string_literal: true`
```
puts %w{a b}[0].frozen?
=> true
puts "hi".frozen?
=> true
puts "a #{1} b".frozen?
=> true
puts ("a " + "b").frozen?
=> false
puts (-("a " + "b")).frozen?
=> true
```
For more details see: https://samsaffron.com/archive/2018/02/16/reducing-string-duplication-in-ruby
In some cases CTE caused pathologically bad query plans.
This optimises it so query runs by itself and caches for lifetime
of the topic query object.
This lightweight caching is done cause topic query will often
execute two queries (one for pinned and one for non pinned)
This feature adds the ability to define synonyms for tags, and the ability to merge one tag into another while keeping it as a synonym. For example, tags named "js" and "java-script" can be synonyms of "javascript". When searching and creating topics using synonyms, they will be mapped to the base tag.
Along with this change is a new UI found on each tag's page (for example, `/tags/javascript`) where more information about the tag can be shown. It will list the synonyms, which categories it's restricted to (if any), and which tag groups it belongs to (if tag group names are public on the `/tags` page by enabling the "tags listed by group" setting). Staff users will be able to manage tags in this UI, merge tags, and add/remove synonyms.
Instead of enabling `suppress_from_latest` setting on many categories now we can enable `mute_all_categories_by_default` site setting. Then users should opt-in to categories for them to appear in the latest and categories pages.
Also:
Move includes call higher which makes it possible to run all of the
intermediate queries for easier debugging.
Add tests for TagsController with categories in the path.
