Revamp post filtering system (#18058)

* 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.

1 files changed, 121 insertions, 0 deletions

diff --git a/spec/controllers/api/v2/filters_controller_spec.rb b/spec/controllers/api/v2/filters_controller_spec.rb
new file mode 100644
index 000000000..cc0070d57
--- /dev/null
+++ b/spec/controllers/api/v2/filters_controller_spec.rb
@@ -0,0 +1,121 @@
+require 'rails_helper'
+
+RSpec.describe Api::V2::FiltersController, type: :controller do
+  render_views
+
+  let(:user)  { Fabricate(:user) }
+  let(:token) { Fabricate(:accessible_access_token, resource_owner_id: user.id, scopes: scopes) }
+
+  before do
+    allow(controller).to receive(:doorkeeper_token) { token }
+  end
+
+  describe 'GET #index' do
+    let(:scopes) { 'read:filters' }
+    let!(:filter) { Fabricate(:custom_filter, account: user.account) }
+
+    it 'returns http success' do
+      get :index
+      expect(response).to have_http_status(200)
+    end
+  end
+
+  describe 'POST #create' do
+    let(:scopes) { 'write:filters' }
+
+    before do
+      post :create, params: { title: 'magic', context: %w(home), filter_action: 'hide', keywords_attributes: [keyword: 'magic'] }
+    end
+
+    it 'returns http success' do
+      expect(response).to have_http_status(200)
+    end
+
+    it 'returns a filter with keywords' do
+      json = body_as_json
+      expect(json[:title]).to eq 'magic'
+      expect(json[:filter_action]).to eq 'hide'
+      expect(json[:context]).to eq ['home']
+      expect(json[:keywords].map { |keyword| keyword.slice(:keyword, :whole_word) }).to eq [{ keyword: 'magic', whole_word: true }]
+    end
+
+    it 'creates a filter' do
+      filter = user.account.custom_filters.first
+      expect(filter).to_not be_nil
+      expect(filter.keywords.pluck(:keyword)).to eq ['magic']
+      expect(filter.context).to eq %w(home)
+      expect(filter.irreversible?).to be true
+      expect(filter.expires_at).to be_nil
+    end
+  end
+
+  describe 'GET #show' do
+    let(:scopes)  { 'read:filters' }
+    let(:filter)  { Fabricate(:custom_filter, account: user.account) }
+
+    it 'returns http success' do
+      get :show, params: { id: filter.id }
+      expect(response).to have_http_status(200)
+    end
+  end
+
+  describe 'PUT #update' do
+    let(:scopes)   { 'write:filters' }
+    let!(:filter)  { Fabricate(:custom_filter, account: user.account) }
+    let!(:keyword) { Fabricate(:custom_filter_keyword, custom_filter: filter) }
+
+    context 'updating filter parameters' do
+      before do
+        put :update, params: { id: filter.id, title: 'updated', context: %w(home public) }
+      end
+
+      it 'returns http success' do
+        expect(response).to have_http_status(200)
+      end
+
+      it 'updates the filter title' do
+        expect(filter.reload.title).to eq 'updated'
+      end
+
+      it 'updates the filter context' do
+        expect(filter.reload.context).to eq %w(home public)
+      end
+    end
+
+    context 'updating keywords in bulk' do
+      before do
+        allow(redis).to receive_messages(publish: nil)
+        put :update, params: { id: filter.id, keywords_attributes: [{ id: keyword.id, keyword: 'updated' }] }
+      end
+
+      it 'returns http success' do
+        expect(response).to have_http_status(200)
+      end
+
+      it 'updates the keyword' do
+        expect(keyword.reload.keyword).to eq 'updated'
+      end
+
+      it 'sends exactly one filters_changed event' do
+        expect(redis).to have_received(:publish).with("timeline:#{user.account.id}", Oj.dump(event: :filters_changed)).once
+      end
+    end
+  end
+
+  describe 'DELETE #destroy' do
+    let(:scopes)  { 'write:filters' }
+    let(:filter)  { Fabricate(:custom_filter, account: user.account) }
+
+    before do
+      delete :destroy, params: { id: filter.id }
+    end
+
+    it 'returns http success' do
+      expect(response).to have_http_status(200)
+    end
+
+    it 'removes the filter' do
+      expect { filter.reload }.to raise_error ActiveRecord::RecordNotFound
+    end
+  end
+end