FEATURE: navigate to first post and auto bump category settings

### navigate_to_first_post_after_read setting for categories

When enabled on categories logged on users will return to OP after
reading the entire category. (useful for documentation categories)

### num_auto_bump_daily

Set a number of topics that will automatically bump daily on a category.

- Every 15 minutes we will check if any category has this setting
- Categories with the setting are shuffled
- We exclude pinned, closed, category description and archived topics
- Maximum of 1 topic for the list of categories is bumped till limit reached per category
- We always try to bump oldest first
- Limit is elastic using a RateLimiter that ensures that we only bump N per day

Also some minor organisation on category settings

Froze strings on category.rb

app/assets/javascripts/discourse/models/category.js.es6

@@ -115,7 +115,10 @@ const Category = RestModel.extend({
         default_view: this.get("default_view"),
         subcategory_list_style: this.get("subcategory_list_style"),
         default_top_period: this.get("default_top_period"),
-        minimum_required_tags: this.get("minimum_required_tags")
+        minimum_required_tags: this.get("minimum_required_tags"),
+        navigate_to_first_post_after_read: this.get(
+          "navigate_to_first_post_after_read"
+        )
       },
       type: id ? "PUT" : "POST"
     });

app/assets/javascripts/discourse/models/topic.js.es6

@@ -212,11 +212,18 @@ const Topic = RestModel.extend({
   }.property("url", "last_read_post_number"),
 
   lastUnreadUrl: function() {
-    const postNumber = Math.min(
+    const highest = this.get("highest_post_number");
-      this.get("last_read_post_number") + 1,
+    const lastRead = this.get("last_read_post_number");
-      this.get("highest_post_number")
+
-    );
+    if (highest <= lastRead) {
-    return this.urlForPostNumber(postNumber);
+      if (this.get("category.navigate_to_first_post_after_read")) {
+        return this.urlForPostNumber(1);
+      } else {
+        return this.urlForPostNumber(lastRead + 1);
+      }
+    } else {
+      return this.urlForPostNumber(lastRead + 1);
+    }
   }.property("url", "last_read_post_number", "highest_post_number"),
 
   lastPostUrl: function() {

app/assets/javascripts/discourse/templates/components/edit-category-settings.hbs

@@ -1,3 +1,19 @@
+{{#if showPositionInput}}
+  <section class='field position-fields'>
+    <label>
+      {{i18n 'category.position'}}
+      {{text-field value=category.position class="position-input" type="number"}}
+    </label>
+  </section>
+{{/if}}
+
+{{#unless showPositionInput}}
+  <section class='field'>
+    {{i18n 'category.position_disabled'}}
+    <a href="/admin/site_settings/category/basic">{{i18n 'category.position_disabled_click'}}</a>
+  </section>
+{{/unless}}
+
 <section class='field'>
   <div class="control-group">
     <label>
@@ -74,14 +90,21 @@
     </div>
 </section>
 
-<section class="field num-featured-topics-fields">
+<section class="field">
   <label>
     {{#if category.parent_category_id}}
       {{i18n "category.subcategory_num_featured_topics"}}
     {{else}}
       {{i18n "category.num_featured_topics"}}
     {{/if}}
-    {{text-field value=category.num_featured_topics}}
+    {{text-field value=category.num_featured_topics type="number"}}
+  </label>
+</section>
+
+<section class="field">
+  <label>
+    {{i18n "category.num_auto_bump_daily"}}
+    {{text-field value=category.custom_fields.num_auto_bump_daily type="number"}}
   </label>
 </section>
 
@@ -92,6 +115,13 @@
   </label>
 </section>
 
+<section class="field">
+  <label>
+    {{input type="checkbox" checked=category.navigate_to_first_post_after_read}}
+    {{i18n "category.navigate_to_first_post_after_read"}}
+  </label>
+</section>
+
 {{#if siteSettings.topic_featured_link_enabled}}
   <section class='field'>
     <div class="allowed-topic-featured-link-category">
@@ -129,29 +159,6 @@
   {{plugin-outlet name="category-email-in" args=(hash category=category)}}
 {{/if}}
 
-{{#if showPositionInput}}
-  <section class='field position-fields'>
-    <label>
-      {{i18n 'category.position'}}
-      {{text-field value=category.position class="position-input"}}
-    </label>
-  </section>
-{{/if}}
-
-{{#unless emailInEnabled}}
-  <section class='field'>
-    {{i18n 'category.email_in_disabled'}}
-    <a href="/admin/site_settings/category/email">{{i18n 'category.email_in_disabled_click'}}</a>
-  </section>
-{{/unless}}
-
-{{#unless showPositionInput}}
-  <section class='field'>
-    {{i18n 'category.position_disabled'}}
-    <a href="/admin/site_settings/category/basic">{{i18n 'category.position_disabled_click'}}</a>
-  </section>
-{{/unless}}
-
 {{#if siteSettings.tagging_enabled}}
   <section class='field minimum-required-tags'>
     <label>
@@ -176,3 +183,10 @@
 </section>
 
 {{plugin-outlet name="category-custom-settings" args=(hash category=category)}}
+
+{{#unless emailInEnabled}}
+  <section class='field'>
+    {{i18n 'category.email_in_disabled'}}
+    <a href="/admin/site_settings/category/email">{{i18n 'category.email_in_disabled_click'}}</a>
+  </section>
+{{/unless}}

app/assets/stylesheets/common/base/modal.scss

@@ -369,12 +369,8 @@
 }
 
 .edit-category-modal {
-  .future-date-input,
+  input[type="number"] {
-  .num-featured-topics-fields,
+    width: 50px;
-  .position-fields {
-    input[type="text"] {
-      width: 50px;
-    }
   }
 
   .subcategory-list-style-field {

app/controllers/categories_controller.rb

@@ -283,6 +283,7 @@ class CategoriesController < ApplicationController
                       :subcategory_list_style,
                       :default_top_period,
                       :minimum_required_tags,
+                      :navigate_to_first_post_after_read,
                       custom_fields: [params[:custom_fields].try(:keys)],
                       permissions: [*p.try(:keys)],
                       allowed_tags: [],

app/jobs/scheduled/periodical_updates.rb

@@ -49,6 +49,14 @@ module Jobs
         SiteSetting.min_new_topics_time = last_new_topic.created_at.to_i
       end
 
+      auto_bumps = CategoryCustomField.where(name: Category::NUM_AUTO_BUMP_DAILY).pluck(:id)
+
+      if (auto_bumps.length > 0)
+        auto_bumps.shuffle.each do |category_id|
+          break if Category.find_by(id: category_id)&.auto_bump_topic!
+        end
+      end
+
       nil
     end
 

app/models/category.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'distributed_cache'
 
 class Category < ActiveRecord::Base
@@ -9,9 +11,11 @@ class Category < ActiveRecord::Base
 
   REQUIRE_TOPIC_APPROVAL = 'require_topic_approval'
   REQUIRE_REPLY_APPROVAL = 'require_reply_approval'
+  NUM_AUTO_BUMP_DAILY = 'num_auto_bump_daily'
 
   register_custom_field_type(REQUIRE_TOPIC_APPROVAL, :boolean)
   register_custom_field_type(REQUIRE_REPLY_APPROVAL, :boolean)
+  register_custom_field_type(NUM_AUTO_BUMP_DAILY, :integer)
 
   belongs_to :topic, dependent: :destroy
   belongs_to :topic_only_relative_url,
@@ -365,6 +369,51 @@ class Category < ActiveRecord::Base
     custom_fields[REQUIRE_REPLY_APPROVAL]
   end
 
+  def num_auto_bump_daily
+    custom_fields[NUM_AUTO_BUMP_DAILY]
+  end
+
+  def num_auto_bump_daily=(v)
+    custom_fields[NUM_AUTO_BUMP_DAILY] = v
+  end
+
+  def auto_bump_limiter
+    RateLimiter.new(nil, "auto_bump_limit_#{self.id}", num_auto_bump_daily.to_i, 86400)
+  end
+
+  def clear_auto_bump_cache!
+    auto_bump_limiter.clear!
+  end
+
+  # will automatically bump a single topic
+  # if number of automatically bumped topics is smaller than threshold
+  def auto_bump_topic!
+    return false if num_auto_bump_daily.blank?
+
+    limiter = auto_bump_limiter
+    return false if !limiter.can_perform?
+
+    id = Topic
+      .visible
+      .listable_topics
+      .where(category_id: self.id)
+      .where('id <> ?', self.topic_id)
+      .where('bumped_at < ?', 1.day.ago)
+      .where('pinned_at IS NULL AND NOT closed AND NOT archived')
+      .order('bumped_at ASC')
+      .limit(1)
+      .pluck(:id).first
+
+    if id
+      Topic.where(id: id).update_all(bumped_at: Time.zone.now)
+      limiter.performed!
+      true
+    else
+      false
+    end
+
+  end
+
   def allowed_tags=(tag_names_arg)
     DiscourseTagging.add_or_create_tags_by_name(self, tag_names_arg, unlimited: true)
   end
@@ -459,12 +508,10 @@ class Category < ActiveRecord::Base
   def url
     url = @@url_cache[self.id]
     unless url
-      url = "#{Discourse.base_uri}/c"
+      url = +"#{Discourse.base_uri}/c"
       url << "/#{parent_category.slug}" if parent_category_id
       url << "/#{slug}"
-      url.freeze
+      @@url_cache[self.id] = -url
-
-      @@url_cache[self.id] = url
     end
 
     url
@@ -545,53 +592,54 @@ end
 #
 # Table name: categories
 #
-#  id                            :integer          not null, primary key
+#  id                                :integer          not null, primary key
-#  name                          :string(50)       not null
+#  name                              :string(50)       not null
-#  color                         :string(6)        default("AB9364"), not null
+#  color                             :string(6)        default("AB9364"), not null
-#  topic_id                      :integer
+#  topic_id                          :integer
-#  topic_count                   :integer          default(0), not null
+#  topic_count                       :integer          default(0), not null
-#  created_at                    :datetime         not null
+#  created_at                        :datetime         not null
-#  updated_at                    :datetime         not null
+#  updated_at                        :datetime         not null
-#  user_id                       :integer          not null
+#  user_id                           :integer          not null
-#  topics_year                   :integer          default(0)
+#  topics_year                       :integer          default(0)
-#  topics_month                  :integer          default(0)
+#  topics_month                      :integer          default(0)
-#  topics_week                   :integer          default(0)
+#  topics_week                       :integer          default(0)
-#  slug                          :string           not null
+#  slug                              :string           not null
-#  description                   :text
+#  description                       :text
-#  text_color                    :string(6)        default("FFFFFF"), not null
+#  text_color                        :string(6)        default("FFFFFF"), not null
-#  read_restricted               :boolean          default(FALSE), not null
+#  read_restricted                   :boolean          default(FALSE), not null
-#  auto_close_hours              :float
+#  auto_close_hours                  :float
-#  post_count                    :integer          default(0), not null
+#  post_count                        :integer          default(0), not null
-#  latest_post_id                :integer
+#  latest_post_id                    :integer
-#  latest_topic_id               :integer
+#  latest_topic_id                   :integer
-#  position                      :integer
+#  position                          :integer
-#  parent_category_id            :integer
+#  parent_category_id                :integer
-#  posts_year                    :integer          default(0)
+#  posts_year                        :integer          default(0)
-#  posts_month                   :integer          default(0)
+#  posts_month                       :integer          default(0)
-#  posts_week                    :integer          default(0)
+#  posts_week                        :integer          default(0)
-#  email_in                      :string
+#  email_in                          :string
-#  email_in_allow_strangers      :boolean          default(FALSE)
+#  email_in_allow_strangers          :boolean          default(FALSE)
-#  topics_day                    :integer          default(0)
+#  topics_day                        :integer          default(0)
-#  posts_day                     :integer          default(0)
+#  posts_day                         :integer          default(0)
-#  allow_badges                  :boolean          default(TRUE), not null
+#  allow_badges                      :boolean          default(TRUE), not null
-#  name_lower                    :string(50)       not null
+#  name_lower                        :string(50)       not null
-#  auto_close_based_on_last_post :boolean          default(FALSE)
+#  auto_close_based_on_last_post     :boolean          default(FALSE)
-#  topic_template                :text
+#  topic_template                    :text
-#  contains_messages             :boolean
+#  contains_messages                 :boolean
-#  sort_order                    :string
+#  sort_order                        :string
-#  sort_ascending                :boolean
+#  sort_ascending                    :boolean
-#  uploaded_logo_id              :integer
+#  uploaded_logo_id                  :integer
-#  uploaded_background_id        :integer
+#  uploaded_background_id            :integer
-#  topic_featured_link_allowed   :boolean          default(TRUE)
+#  topic_featured_link_allowed       :boolean          default(TRUE)
-#  all_topics_wiki               :boolean          default(FALSE), not null
+#  all_topics_wiki                   :boolean          default(FALSE), not null
-#  show_subcategory_list         :boolean          default(FALSE)
+#  show_subcategory_list             :boolean          default(FALSE)
-#  num_featured_topics           :integer          default(3)
+#  num_featured_topics               :integer          default(3)
-#  default_view                  :string(50)
+#  default_view                      :string(50)
-#  subcategory_list_style        :string(50)       default("rows_with_featured_topics")
+#  subcategory_list_style            :string(50)       default("rows_with_featured_topics")
-#  default_top_period            :string(20)       default("all")
+#  default_top_period                :string(20)       default("all")
-#  mailinglist_mirror            :boolean          default(FALSE), not null
+#  mailinglist_mirror                :boolean          default(FALSE), not null
-#  suppress_from_latest          :boolean          default(FALSE)
+#  suppress_from_latest              :boolean          default(FALSE)
-#  minimum_required_tags         :integer          default(0)
+#  minimum_required_tags             :integer          default(0)
+#  navigate_to_first_post_after_read :boolean          default(FALSE), not null
 #
 # Indexes
 #

app/serializers/basic_category_serializer.rb

@@ -25,7 +25,8 @@ class BasicCategorySerializer < ApplicationSerializer
              :default_view,
              :subcategory_list_style,
              :default_top_period,
-             :minimum_required_tags
+             :minimum_required_tags,
+             :navigate_to_first_post_after_read
 
   has_one :uploaded_logo, embed: :object, serializer: CategoryUploadSerializer
   has_one :uploaded_background, embed: :object, serializer: CategoryUploadSerializer

config/locales/client.en.yml

@@ -2275,7 +2275,7 @@ en:
       show_subcategory_list: "Show subcategory list above topics in this category."
       num_featured_topics: "Number of topics shown on the categories page:"
       subcategory_num_featured_topics: "Number of featured topics on parent category's page:"
-      all_topics_wiki: "Make new topics wikis by default."
+      all_topics_wiki: "Make new topics wikis by default"
       subcategory_list_style: "Subcategory List Style:"
       sort_order: "Topic List Sort By:"
       default_view: "Default Topic List:"
@@ -2286,12 +2286,14 @@ en:
       require_topic_approval: "Require moderator approval of all new topics"
       require_reply_approval: "Require moderator approval of all new replies"
       this_year: "this year"
-      position: "position"
+      position: "Position:"
       default_position: "Default Position"
       position_disabled: "Categories will be displayed in order of activity. To control the order of categories in lists, "
       position_disabled_click: 'enable the "fixed category positions" setting.'
       minimum_required_tags: 'Minimum number of tags required in a topic:'
       parent: "Parent Category"
+      num_auto_bump_daily: 'Number of open topics to automatically bump daily:'
+      navigate_to_first_post_after_read: 'Navigate to first post after topics are read'
       notifications:
         watching:
           title: "Watching"

db/migrate/20180716062405_add_navigate_to_first_post_after_read_to_categories.rb

@@ -0,0 +1,5 @@
+class AddNavigateToFirstPostAfterReadToCategories < ActiveRecord::Migration[5.2]
+  def change
+    add_column :categories, :navigate_to_first_post_after_read, :bool, null: false, default: false
+  end
+end

spec/models/category_spec.rb

@@ -684,4 +684,44 @@ describe Category do
       it { expect(category.reload.require_reply_approval?).to eq(true) }
     end
   end
+
+  describe 'auto bump' do
+    before do
+      RateLimiter.enable
+    end
+
+    after do
+      RateLimiter.disable
+    end
+
+    it 'should correctly automatically bump topics' do
+      freeze_time 1.second.ago
+      category = Fabricate(:category)
+      category.clear_auto_bump_cache!
+
+      _post1 = create_post(category: category)
+      _post2 = create_post(category: category)
+      _post3 = create_post(category: category)
+
+      time = 1.month.from_now
+      freeze_time time
+
+      expect(category.auto_bump_topic!).to eq(false)
+      expect(Topic.where(bumped_at: time).count).to eq(0)
+
+      category.num_auto_bump_daily = 2
+      category.save!
+
+      expect(category.auto_bump_topic!).to eq(true)
+      expect(Topic.where(bumped_at: time).count).to eq(1)
+
+      expect(category.auto_bump_topic!).to eq(true)
+      expect(Topic.where(bumped_at: time).count).to eq(2)
+
+      expect(category.auto_bump_topic!).to eq(false)
+      expect(Topic.where(bumped_at: time).count).to eq(2)
+
+    end
+  end
+
 end

spec/requests/categories_controller_spec.rb

@@ -297,24 +297,31 @@ describe CategoriesController do
           expect(UserHistory.count).to eq(5) # 2 + 3 (bootstrap mode)
         end
 
-        it 'updates per-category approval settings correctly' do
+        it 'updates per-category settings correctly' do
           category.custom_fields[Category::REQUIRE_TOPIC_APPROVAL] = false
           category.custom_fields[Category::REQUIRE_REPLY_APPROVAL] = false
+          category.custom_fields[Category::NUM_AUTO_BUMP_DAILY] = 0
+
+          category.navigate_to_first_post_after_read = false
           category.save!
 
           put "/categories/#{category.id}.json", params: {
             name: category.name,
             color: category.color,
             text_color: category.text_color,
+            navigate_to_first_post_after_read: true,
             custom_fields: {
               require_reply_approval: true,
               require_topic_approval: true,
+              num_auto_bump_daily: 10
             }
           }
 
           category.reload
           expect(category.require_topic_approval?).to eq(true)
           expect(category.require_reply_approval?).to eq(true)
+          expect(category.num_auto_bump_daily).to eq(10)
+          expect(category.navigate_to_first_post_after_read).to eq(true)
         end
       end
     end

test/javascripts/models/topic-test.js.es6

@@ -32,6 +32,23 @@ QUnit.test("visited", assert => {
   );
 });
 
+QUnit.test("lastUnreadUrl", assert => {
+  const category = Em.Object.create({
+    navigate_to_first_post_after_read: true
+  });
+
+  const topic = Topic.create({
+    id: 101,
+    highest_post_number: 10,
+    last_read_post_number: 10,
+    slug: "hello"
+  });
+
+  topic.set("category", category);
+
+  assert.equal(topic.get("lastUnreadUrl"), "/t/hello/101/1");
+});
+
 QUnit.test("has details", assert => {
   const topic = Topic.create({ id: 1234 });
   const topicDetails = topic.get("details");