We were previously showing the "n new or updated topics" alert on
category routes like `/c/category-slug/ID/none` on every new/unread
topic update. This PR looks up the category by ID, which should be more
precise.
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).
----
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.
Original PR was reverted because of broken migration https://github.com/discourse/discourse/pull/12058
I fixed it by adding this line
```
AND topics.id IN(SELECT id FROM topics ORDER BY created_at DESC LIMIT :max_new_topics)
```
This time it is left joining a limited amount of topics. I tested it on few databases and it worked quite smooth
Follow up https://github.com/discourse/discourse/pull/11968
Dismiss all new topics using the same DismissTopicService. In addition, MessageBus receives exact topic ids which should be marked as `seen`.
* FEATURE: Ability to dismiss new topics in a specific tag
Follow up of https://github.com/discourse/discourse/pull/11927
Using the same mechanism to disable new topics in a tag.
* FIX: respect when category and tag is selected
Using arrow functions changes `this` context, which is undesired in tests, e.g. it makes it impossible to setup things like pretender (`this.server`) in `beforeEach` hooks.
Ember guides always use classic functions in examples (e.g. https://guides.emberjs.com/release/testing/test-types/), and that's what it uses in its own test suite, as do various addons and ember apps.
It was also already used in Discourse where `this` was required. Moving forward, it will be needed in more places as we migrate toward ember-cli.
(I might later add a custom rule to eslint-discourse-ember to enforce this)
I also took the opportunity with this commit to move some test specific
stuff out of `discourse-loader` which is loaded on the front end of the
application. The test module building now happens in the `test_helper`
bundle.
We used many global functions to handle tests when they should be
imported like other libraries in our application. This also gets us
closer to the way Ember CLI prefers our tests to be laid out.
This is where they should be as far as ember is concerned. Note this is
a huge commit and we should be really careful everything continues to
work properly.