FEATURE: Stream topic summaries. (#23065)

When we receive the stream parameter, we'll queue a job that periodically publishes partial updates, and after the summarization finishes, a final one with the completed version, plus metadata.

`summary-box` listens to these updates via MessageBus, and updates state accordingly.

spec/jobs/regular/stream_topic_summary_spec.rb

@@ -0,0 +1,76 @@
+# frozen_string_literal: true
+
+RSpec.describe Jobs::StreamTopicSummary do
+  subject(:job) { described_class.new }
+
+  describe "#execute" do
+    fab!(:topic) { Fabricate(:topic) }
+    let(:plugin) { Plugin::Instance.new }
+    let(:strategy) { DummyCustomSummarization.new({ summary: "dummy", chunks: [] }) }
+    fab!(:user) { Fabricate(:leader) }
+
+    before { Group.find(Group::AUTO_GROUPS[:trust_level_3]).add(user) }
+
+    before do
+      plugin.register_summarization_strategy(strategy)
+      SiteSetting.summarization_strategy = strategy.model
+    end
+
+    describe "validates params" do
+      it "does nothing if there is no topic" do
+        messages =
+          MessageBus.track_publish("/summaries/topic/#{topic.id}") do
+            job.execute(topic_id: nil, user_id: user.id)
+          end
+
+        expect(messages).to be_empty
+      end
+
+      it "does nothing if there is no user" do
+        messages =
+          MessageBus.track_publish("/summaries/topic/#{topic.id}") do
+            job.execute(topic_id: topic.id, user_id: nil)
+          end
+
+        expect(messages).to be_empty
+      end
+
+      it "does nothing if the user is not allowed to see the topic" do
+        private_topic = Fabricate(:private_message_topic)
+
+        messages =
+          MessageBus.track_publish("/summaries/topic/#{private_topic.id}") do
+            job.execute(topic_id: private_topic.id, user_id: user.id)
+          end
+
+        expect(messages).to be_empty
+      end
+    end
+
+    it "publishes updates with a partial summary" do
+      messages =
+        MessageBus.track_publish("/summaries/topic/#{topic.id}") do
+          job.execute(topic_id: topic.id, user_id: user.id)
+        end
+
+      partial_summary_update = messages.first.data
+      expect(partial_summary_update[:done]).to eq(false)
+      expect(partial_summary_update.dig(:topic_summary, :summarized_text)).to eq("dummy")
+    end
+
+    it "publishes a final update to signal we're done and provide metadata" do
+      messages =
+        MessageBus.track_publish("/summaries/topic/#{topic.id}") do
+          job.execute(topic_id: topic.id, user_id: user.id)
+        end
+
+      final_update = messages.last.data
+      expect(final_update[:done]).to eq(true)
+
+      expect(final_update.dig(:topic_summary, :algorithm)).to eq(strategy.model)
+      expect(final_update.dig(:topic_summary, :outdated)).to eq(false)
+      expect(final_update.dig(:topic_summary, :can_regenerate)).to eq(true)
+      expect(final_update.dig(:topic_summary, :new_posts_since_summary)).to be_zero
+    end
+  end
+end

spec/requests/topics_controller_spec.rb

@@ -5508,9 +5508,9 @@ RSpec.describe TopicsController do
   describe "#summary" do
     fab!(:topic) { Fabricate(:topic) }
     let(:plugin) { Plugin::Instance.new }
+    let(:strategy) { DummyCustomSummarization.new({ summary: "dummy", chunks: [] }) }
 
     before do
-      strategy = DummyCustomSummarization.new("dummy")
       plugin.register_summarization_strategy(strategy)
       SiteSetting.summarization_strategy = strategy.model
     end
@@ -5536,14 +5536,17 @@ RSpec.describe TopicsController do
         expect(response.status).to eq(200)
 
         summary = response.parsed_body
-        expect(summary["summary"]).to eq(section.summarized_text)
+        expect(summary.dig("topic_summary", "summarized_text")).to eq(section.summarized_text)
       end
     end
 
     context "when the user is a member of an allowlisted group" do
       fab!(:user) { Fabricate(:leader) }
 
-      before { sign_in(user) }
+      before do
+        sign_in(user)
+        Group.find(Group::AUTO_GROUPS[:trust_level_3]).add(user)
+      end
 
       it "returns a 404 if there is no topic" do
         invalid_topic_id = 999
@@ -5560,6 +5563,20 @@ RSpec.describe TopicsController do
 
         expect(response.status).to eq(403)
       end
+
+      it "returns a summary" do
+        get "/t/#{topic.id}/strategy-summary.json"
+
+        expect(response.status).to eq(200)
+        summary = response.parsed_body["topic_summary"]
+        section = SummarySection.last
+
+        expect(summary["summarized_text"]).to eq(section.summarized_text)
+        expect(summary["algorithm"]).to eq(strategy.model)
+        expect(summary["outdated"]).to eq(false)
+        expect(summary["can_regenerate"]).to eq(true)
+        expect(summary["new_posts_since_summary"]).to be_zero
+      end
     end
 
     context "when the user is not a member of an allowlisted group" do
@@ -5587,7 +5604,7 @@ RSpec.describe TopicsController do
         expect(response.status).to eq(200)
 
         summary = response.parsed_body
-        expect(summary["summary"]).to eq(section.summarized_text)
+        expect(summary.dig("topic_summary", "summarized_text")).to eq(section.summarized_text)
       end
     end
   end

spec/services/topic_summarization_spec.rb

@@ -186,5 +186,17 @@ describe TopicSummarization do
         end
       end
     end
+
+    describe "stream partial updates" do
+      let(:summary) { { summary: "This is the final summary", chunks: [] } }
+
+      it "receives a blk that is passed to the underlying strategy and called with partial summaries" do
+        partial_result = nil
+
+        summarization.summarize(topic, user) { |partial_summary| partial_result = partial_summary }
+
+        expect(partial_result).to eq(summary[:summary])
+      end
+    end
   end
 end

spec/support/dummy_custom_summarization.rb

@@ -22,6 +22,6 @@ class DummyCustomSummarization < Summarization::Base
   end
 
   def summarize(_content)
-    @summarization_result
+    @summarization_result.tap { |result| yield(result[:summary]) if block_given? }
   end
 end

spec/system/topic_summarization_spec.rb

@@ -1,32 +0,0 @@
-# frozen_string_literal: true
-
-RSpec.describe "Topic summarization", type: :system, js: true do
-  fab!(:user) { Fabricate(:admin) }
-
-  # has_summary to force topic map to be present.
-  fab!(:topic) { Fabricate(:topic, has_summary: true) }
-  fab!(:post_1) { Fabricate(:post, topic: topic) }
-  fab!(:post_2) { Fabricate(:post, topic: topic) }
-
-  let(:plugin) { Plugin::Instance.new }
-
-  let(:expected_summary) { "This is a summary" }
-  let(:summarization_result) { { summary: expected_summary, chunks: [] } }
-
-  before do
-    sign_in(user)
-    strategy = DummyCustomSummarization.new(summarization_result)
-    plugin.register_summarization_strategy(strategy)
-    SiteSetting.summarization_strategy = strategy.model
-  end
-
-  it "returns a summary using the selected timeframe" do
-    visit("/t/-/#{topic.id}")
-
-    find(".topic-strategy-summarization").click
-
-    summary = find(".summary-box .generated-summary p").text
-
-    expect(summary).to eq(expected_summary)
-  end
-end