* Change how hashtags are normalized

* Fix tests

* Add model for custom filter keywords

* Use CustomFilterKeyword internally

Does not change the API

* Fix /filters/edit and /filters/new

* Add migration tests

* Remove whole_word column from custom_filters (covered by custom_filter_keywords)

* Redesign /filters

Instead of a list, present a card that displays more information and handles
multiple keywords per filter.

* Redesign /filters/new and /filters/edit to add and remove keywords

This adds a new gem dependency: cocoon, as well as a npm dependency:
cocoon-js-vanilla. Those are used to easily populate and remove form fields
from the user interface when manipulating multiple keyword filters at once.

* Add /api/v2/filters to edit filter with multiple keywords

Entities:
- `Filter`: `id`, `title`, `filter_action` (either `hide` or `warn`), `context`
  `keywords`
- `FilterKeyword`: `id`, `keyword`, `whole_word`

API endpoits:
- `GET /api/v2/filters` to list filters (including keywords)
- `POST /api/v2/filters` to create a new filter
  `keywords_attributes` can also be passed to create keywords in one request
- `GET /api/v2/filters/:id` to read a particular filter
- `PUT /api/v2/filters/:id` to update a new filter
  `keywords_attributes` can also be passed to edit, delete or add keywords in
   one request
- `DELETE /api/v2/filters/:id` to delete a particular filter
- `GET /api/v2/filters/:id/keywords` to list keywords for a filter
- `POST /api/v2/filters/:filter_id/keywords/:id` to add a new keyword to a
   filter
- `GET /api/v2/filter_keywords/:id` to read a particular keyword
- `PUT /api/v2/filter_keywords/:id` to edit a particular keyword
- `DELETE /api/v2/filter_keywords/:id` to delete a particular keyword

* Change from `irreversible` boolean to `action` enum

* Remove irrelevent `irreversible_must_be_within_context` check

* Fix /filters/new and /filters/edit with update for filter_action

* Fix Rubocop/Codeclimate complaining about task names

* Refactor FeedManager#phrase_filtered?

This moves regexp building and filter caching to the `CustomFilter` class.

This does not change the functional behavior yet, but this changes how the
cache is built, doing per-custom_filter regexps so that filters can be matched
independently, while still offering caching.

* Perform server-side filtering and output result in REST API

* Fix numerous filters_changed events being sent when editing multiple keywords at once

* Add some tests

* Use the new API in the WebUI

- use client-side logic for filters we have fetched rules for.
  This is so that filter changes can be retroactively applied without
  reloading the UI.
- use server-side logic for filters we haven't fetched rules for yet
  (e.g. network error, or initial timeline loading)

* Minor optimizations and refactoring

* Perform server-side filtering on the streaming server

* Change the wording of filter action labels

* Fix issues pointed out by linter

* Change design of “Show anyway” link in accordence to review comments

* Drop “irreversible” filtering behavior

* Move /api/v2/filter_keywords to /api/v1/filters/keywords

* Rename `filter_results` attribute to `filtered`

* Rename REST::LegacyFilterSerializer to REST::V1::FilterSerializer

* Fix systemChannelId value in streaming server

* Simplify code by removing client-side filtering code

The simplifcation comes at a cost though: filters aren't retroactively
applied anymore.

Fixes #17541

- prefix JSON parsing error message by “Error parsing message from …”
- output user id if a user is logged in, IP address otherwise
- reduce log level from error to warning when a user is logged in, and to silly
  otherwise

* Fix timeline streaming stopping for multiple sessions instead of one

Fixes #17256.

In updating the code for a newer version of node-redis, #17183 also broke
redis subscription management when multiple streaming clients subscribe to the
same channel.

This commit restores the redis subscription management code.

* Let node-redis actually handle the subscriptions

* fix streaming redis client

* use console.error instead of console.log

* follow node-redis migration guide

https://github.com/redis/node-redis/blob/master/docs/v3-to-v4.md



* fix config options for node-redis

* keep indentation

* Update streaming/index.js

Co-authored-by: Yamagishi Kazutoshi <ykzts@desire.sh>

Co-authored-by: Yamagishi Kazutoshi <ykzts@desire.sh>

When checking for required OAuth scopes, an unexpected error could
happen due to missing (null-y) req.scopes. This commit fixes that by
checking if req.scopes are present before checking if any required
scopes are present, otherwise it skips that straight to rejection.

Eliminate need to have custom notifications filtering logic in the
streaming API code by publishing notifications into a separate stream
and then simply using the multi-stream capability to subscribe to that
stream when necessary

Third argument of `ping` is the callback

Regression from #15932

* Switch from deprecated ClusterWS/cws to ws package

Fixes #15184

Co-authored-by: Edho Arief <me@nanaya.pro>

* Make bufferutil and utf-8-validate optional dependencies

Co-authored-by: Edho Arief <me@nanaya.pro>

* eslint --fix

* fix consistent-return

* fix promise/catch-or-return

* ignore import rule

Fix #14816

Fixes #14131

Our `mastodon:setup` task defaults to a blank password rather than the
absence of password, but some versions of Redis reject blank password
authentication when authentication is possible without a password.

The Ruby code only uses the Redis password when it's not blank, so
do the same for the node.js part.

* Add remote only to public timeline

* Fix code style

* Send output on the server-sent events stream immediately so the client sees that it was successfully opened even if it doesn't have any messages.

Fix transparent SSE streaming for the public:local and hashtag:local stream types.

* Tell caches to never store server-sent events.

* Check OAuth token scopes in the streaming API

* Use Sec-WebSocket-Protocol instead of query string to pass WebSocket token

Inspired by https://github.com/kubevirt/kubevirt/issues/1242

Fix #10223

* Fix SSL configuration regression in streaming API

Fix #10223

* Fix code style issues and integrate #10219

* Fix dumb thing

* config: add DB_SSLMODE for managed/remote PG

* streaming: set PG sslmode, defaults to prefer

Previously, the server would attempt taking port/socket in worker
process, and if it was taken, fail, which made the master process
create a new worker. This led to really high CPU usage if the
streaming API was started when the port or socket were not
available.

Now, before clustering (forking) into worker processes, a test
server is created and then removed to check if it can be done.

* Add check for missing tag param in streaming API

Fixes error:

```
TypeError: Cannot read property 'toLowerCase' of undefined
at app.get (.../streaming/index.js:493:50)
```

* Fix code style issues

* Add conversations API

* Add web UI for conversations

* Add test for conversations API

* Add tests for ConversationAccount

* Improve web UI

* Rename ConversationAccount to AccountConversation

* Remove conversations on block and mute

* Change last_status_id to be a denormalization of status_ids

* Add optimistic locking

GET /api/v1/streaming/health

Answers with OK. Fix #8337

* Support UNIX domain socket for streaming service without using PORT

The use of UNIX domain socket for streaming service was not officially supported,
but it was made unofficial to use by setting a path to PORT.
From now on, SOCKET will be used just like setting for puma.

* Hundle relative path

* Added a timeline for Direct statuses
* Lists all Direct statuses you've sent and received
* Displayed in Getting Started
* Streaming server support for direct TL

* Changes to match other timelines in 2.0