Use the same component for similar topics as search results.

app/assets/javascripts/discourse/controllers/composer.js.es6

@@ -332,7 +332,7 @@ export default Ember.ObjectController.extend(Presence, {
       this.set('similarTopicsMessage', message);
     }
 
-    this.store.find('topic', {similar: {title, raw: body}}).then(function(newTopics) {
+    this.store.find('similar-topic', {title, raw: body}).then(function(newTopics) {
       similarTopics.clear();
       similarTopics.pushObjects(newTopics.get('content'));
 

app/assets/javascripts/discourse/lib/url.js

@@ -109,7 +109,6 @@ Discourse.URL = Ember.Object.createWithMixins({
     @param {String} path The path we are routing to.
   **/
   routeTo: function(path) {
-
     if (Em.isEmpty(path)) { return; }
 
     if (Discourse.get('requiresRefresh')) {

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

@@ -143,10 +143,13 @@ export default Ember.Object.extend({
     return this.container.lookup('adapter:' + type) || this.container.lookup('adapter:rest');
   },
 
-  _lookupSubType(subType, id, root) {
+  _lookupSubType(subType, type, id, root) {
 
     // cheat: we know we already have categories in memory
-    if (subType === 'category') {
+    // TODO: topics do their own resolving of `category_id`
+    // to category. That should either respect this or be
+    // removed.
+    if (subType === 'category' && type !== 'topic') {
       return Discourse.Category.findById(id);
     }
 
@@ -172,13 +175,13 @@ export default Ember.Object.extend({
     }
   },
 
-  _hydrateEmbedded(obj, root) {
+  _hydrateEmbedded(type, obj, root) {
     const self = this;
     Object.keys(obj).forEach(function(k) {
       const m = /(.+)\_id$/.exec(k);
       if (m) {
         const subType = m[1];
-        const hydrated = self._lookupSubType(subType, obj[k], root);
+        const hydrated = self._lookupSubType(subType, type, obj[k], root);
         if (hydrated) {
           obj[subType] = hydrated;
           delete obj[k];
@@ -196,7 +199,7 @@ export default Ember.Object.extend({
     // Experimental: If serialized with a certain option we'll wire up embedded objects
     // automatically.
     if (root.__rest_serializer === "1") {
-      this._hydrateEmbedded(obj, root);
+      this._hydrateEmbedded(type, obj, root);
     }
 
     const existing = fromMap(type, obj.id);

app/assets/javascripts/discourse/routes/build-topic-route.js.es6

@@ -16,6 +16,7 @@ function findTopicList(store, filter, filterParams, extras) {
 
   extras = extras || {};
   return new Ember.RSVP.Promise(function(resolve) {
+
     const session = Discourse.Session.current();
 
     if (extras.cached) {
@@ -80,7 +81,6 @@ export default function(filter, extras) {
     },
 
     model(data, transition) {
-
       // attempt to stop early cause we need this to be called before .sync
       Discourse.ScreenTrack.current().stop();
 

app/assets/javascripts/discourse/templates/composer/similar_topics.hbs

@@ -2,11 +2,5 @@
 <h3>{{i18n 'composer.similar_topics'}}</h3>
 
 <ul class='topics'>
-  {{#each similarTopics as |t|}}
-    <li>
-      {{topic-status topic=t}}
-      {{topic-link t}}
-      {{category-link t.category}}
-    </li>
-  {{/each}}
+  {{search-result-topic results=similarTopics}}
 </ul>

app/assets/stylesheets/desktop/compose.scss

@@ -74,6 +74,17 @@
   .posts-count {
     background-color: scale-color($tertiary, $lightness: -40%);
   }
+
+  ul {
+    list-style: none;
+    margin: 0;
+    padding: 0;
+  }
+  .search-link {
+    .fa, .blurb {
+      color: scale-color($tertiary, $lightness: -40%);
+    }
+  }
 }
 
 .composer-popup:nth-of-type(2) {

app/controllers/similar_topics_controller.rb

@@ -0,0 +1,39 @@
+require_dependency 'similar_topic_serializer'
+require_dependency 'search/grouped_search_results'
+
+class SimilarTopicsController < ApplicationController
+
+  class SimilarTopic
+    def initialize(topic)
+      @topic = topic
+    end
+
+    attr_reader :topic
+
+    def blurb
+      Search::GroupedSearchResults.blurb_for(@topic.try(:blurb))
+    end
+  end
+
+  def index
+    params.require(:title)
+    params.require(:raw)
+    title, raw = params[:title], params[:raw]
+    [:title, :raw].each { |key| check_length_of(key, params[key]) }
+
+    # Only suggest similar topics if the site has a minimum amount of topics present.
+    return render json: [] unless Topic.count_exceeds_minimum?
+
+    topics = Topic.similar_to(title, raw, current_user).to_a
+    topics.map! {|t| SimilarTopic.new(t) }
+    render_serialized(topics, SimilarTopicSerializer, root: :similar_topics, rest_serializer: true)
+  end
+
+  protected
+
+    def check_length_of(key, attr)
+      str = (key == :raw) ? "body" : key.to_s
+      raise Discourse::InvalidParameters.new(key) if attr.length < SiteSetting.send("min_#{str}_similar_length")
+    end
+
+end

app/controllers/topics_controller.rb

@@ -149,19 +149,6 @@ class TopicsController < ApplicationController
     success ? render_serialized(topic, BasicTopicSerializer) : render_json_error(topic)
   end
 
-  def similar_to
-    params.require(:title)
-    params.require(:raw)
-    title, raw = params[:title], params[:raw]
-    [:title, :raw].each { |key| check_length_of(key, params[key]) }
-
-    # Only suggest similar topics if the site has a minimum amount of topics present.
-    return render json: [] unless Topic.count_exceeds_minimum?
-
-    topics = Topic.similar_to(title, raw, current_user).to_a
-    render_serialized(topics, TopicListItemSerializer, root: :topics)
-  end
-
   def feature_stats
     params.require(:category_id)
     category_id = params[:category_id].to_i
@@ -510,11 +497,6 @@ class TopicsController < ApplicationController
     topic.move_posts(current_user, post_ids_including_replies, args)
   end
 
-  def check_length_of(key, attr)
-    str = (key == :raw) ? "body" : key.to_s
-    invalid_param(key) if attr.length < SiteSetting.send("min_#{str}_similar_length")
-  end
-
   def check_for_status_presence(key, attr)
     invalid_param(key) unless %w(pinned pinned_globally visible closed archived).include?(attr)
   end

app/models/topic.rb

@@ -397,7 +397,7 @@ class Topic < ActiveRecord::Base
 
     return [] unless candidate_ids.present?
 
-    similar = Topic.select(sanitize_sql_array(["topics.*, similarity(topics.title, :title) + similarity(topics.title, :raw) AS similarity", title: title, raw: raw]))
+    similar = Topic.select(sanitize_sql_array(["topics.*, similarity(topics.title, :title) + similarity(topics.title, :raw) AS similarity, p.cooked as blurb", title: title, raw: raw]))
                      .joins("JOIN posts AS p ON p.topic_id = topics.id AND p.post_number = 1")
                      .limit(SiteSetting.max_similar_results)
                      .where("topics.id IN (?)", candidate_ids)

app/serializers/similar_topic_serializer.rb

@@ -0,0 +1,17 @@
+class SimilarTopicSerializer < ApplicationSerializer
+
+  has_one :topic, serializer: TopicListItemSerializer, embed: :ids
+  attributes :id, :blurb, :created_at
+
+  def id
+    object.topic.id
+  end
+
+  def blurb
+    object.blurb
+  end
+
+  def created_at
+    object.topic.created_at
+  end
+end

config/routes.rb

@@ -410,7 +410,10 @@ Discourse::Application.routes.draw do
   put "topics/bulk"
   put "topics/reset-new" => 'topics#reset_new'
   post "topics/timings"
-  get "topics/similar_to"
+
+  get 'topics/similar_to' => 'similar_topics#index'
+  resources :similar_topics
+
   get "topics/feature_stats"
   get "topics/created-by/:username" => "list#topics_by", as: "topics_by", constraints: {username: USERNAME_ROUTE_FORMAT}
   get "topics/private-messages/:username" => "list#private_messages", as: "topics_private_messages", constraints: {username: USERNAME_ROUTE_FORMAT}

lib/search/grouped_search_results.rb

@@ -3,7 +3,6 @@ require 'sanitize'
 class Search
 
   class GroupedSearchResults
-
     include ActiveModel::Serialization
 
     class TextHelper
@@ -26,11 +25,7 @@ class Search
     end
 
     def blurb(post)
-      cooked = SearchObserver::HtmlScrubber.scrub(post.cooked).squish
-      terms = @term.split(/\s+/)
-      blurb = TextHelper.excerpt(cooked, terms.first, radius: 100)
-      blurb = TextHelper.truncate(cooked, length: 200) if blurb.blank?
-      Sanitize.clean(blurb)
+      GroupedSearchResults.blurb_for(post.cooked, @term)
     end
 
     def add(object)
@@ -43,6 +38,18 @@ class Search
       end
     end
 
+
+    def self.blurb_for(cooked, term=nil)
+      cooked = SearchObserver::HtmlScrubber.scrub(cooked).squish
+
+      blurb = nil
+      if term
+        terms = term.split(/\s+/)
+        blurb = TextHelper.excerpt(cooked, terms.first, radius: 100)
+      end
+      blurb = TextHelper.truncate(cooked, length: 200) if blurb.blank?
+      Sanitize.clean(blurb)
+    end
   end
 
 end

spec/controllers/similar_topics_controller_spec.rb

@@ -0,0 +1,66 @@
+require 'spec_helper'
+
+describe SimilarTopicsController do
+  context 'similar_to' do
+
+    let(:title) { 'this title is long enough to search for' }
+    let(:raw) { 'this body is long enough to search for' }
+
+    it "requires a title" do
+      expect { xhr :get, :index, raw: raw }.to raise_error(ActionController::ParameterMissing)
+    end
+
+    it "requires a raw body" do
+      expect { xhr :get, :index, title: title }.to raise_error(ActionController::ParameterMissing)
+    end
+
+    it "raises an error if the title length is below the minimum" do
+      SiteSetting.stubs(:min_title_similar_length).returns(100)
+      expect { xhr :get, :index, title: title, raw: raw }.to raise_error(Discourse::InvalidParameters)
+    end
+
+    it "raises an error if the body length is below the minimum" do
+      SiteSetting.stubs(:min_body_similar_length).returns(100)
+      expect { xhr :get, :index, title: title, raw: raw }.to raise_error(Discourse::InvalidParameters)
+    end
+
+    describe "minimum_topics_similar" do
+
+      before do
+        SiteSetting.stubs(:minimum_topics_similar).returns(30)
+      end
+
+      after do
+        xhr :get, :index, title: title, raw: raw
+      end
+
+      describe "With enough topics" do
+        before do
+          Topic.stubs(:count).returns(50)
+        end
+
+        it "deletes to Topic.similar_to if there are more topics than `minimum_topics_similar`" do
+          Topic.expects(:similar_to).with(title, raw, nil).returns([Fabricate(:topic)])
+        end
+
+        describe "with a logged in user" do
+          let(:user) { log_in }
+
+          it "passes a user through if logged in" do
+            Topic.expects(:similar_to).with(title, raw, user).returns([Fabricate(:topic)])
+          end
+        end
+
+      end
+
+      it "does not call Topic.similar_to if there are fewer topics than `minimum_topics_similar`" do
+        Topic.stubs(:count).returns(10)
+        Topic.expects(:similar_to).never
+      end
+
+    end
+
+  end
+
+end
+

spec/controllers/topics_controller_spec.rb

@@ -245,68 +245,6 @@ describe TopicsController do
     end
   end
 
-  context 'similar_to' do
-
-    let(:title) { 'this title is long enough to search for' }
-    let(:raw) { 'this body is long enough to search for' }
-
-    it "requires a title" do
-      expect { xhr :get, :similar_to, raw: raw }.to raise_error(ActionController::ParameterMissing)
-    end
-
-    it "requires a raw body" do
-      expect { xhr :get, :similar_to, title: title }.to raise_error(ActionController::ParameterMissing)
-    end
-
-    it "raises an error if the title length is below the minimum" do
-      SiteSetting.stubs(:min_title_similar_length).returns(100)
-      expect { xhr :get, :similar_to, title: title, raw: raw }.to raise_error(Discourse::InvalidParameters)
-    end
-
-    it "raises an error if the body length is below the minimum" do
-      SiteSetting.stubs(:min_body_similar_length).returns(100)
-      expect { xhr :get, :similar_to, title: title, raw: raw }.to raise_error(Discourse::InvalidParameters)
-    end
-
-    describe "minimum_topics_similar" do
-
-      before do
-        SiteSetting.stubs(:minimum_topics_similar).returns(30)
-      end
-
-      after do
-        xhr :get, :similar_to, title: title, raw: raw
-      end
-
-      describe "With enough topics" do
-        before do
-          Topic.stubs(:count).returns(50)
-        end
-
-        it "deletes to Topic.similar_to if there are more topics than `minimum_topics_similar`" do
-          Topic.expects(:similar_to).with(title, raw, nil).returns([Fabricate(:topic)])
-        end
-
-        describe "with a logged in user" do
-          let(:user) { log_in }
-
-          it "passes a user through if logged in" do
-            Topic.expects(:similar_to).with(title, raw, user).returns([Fabricate(:topic)])
-          end
-        end
-
-      end
-
-      it "does not call Topic.similar_to if there are fewer topics than `minimum_topics_similar`" do
-        Topic.stubs(:count).returns(10)
-        Topic.expects(:similar_to).never
-      end
-
-    end
-
-  end
-
-
   context 'clear_pin' do
     it 'needs you to be logged in' do
       expect { xhr :put, :clear_pin, topic_id: 1 }.to raise_error(Discourse::NotLoggedIn)