Log and notify Sentry when relevant articles are not retrieved. (#2186)

* Log and notify Sentry when relevant articles are not retrieved.

This PR implements two things:

* Case 1: Info-level logging when no relevant articles are returned.
* Case 2: Notify Sentry when there is an error retrieving relevant articles. In that case:
  * Catch the error and return an empty list, so it doesn't crash the frontend, which can then retrieve to recent articles.
  * Log a warning.
  * Notify Sentry. The Sentry message is static and implements a custom exception class, so similar notifications can be grouped together automatically, but includes all information we need in order to debug.

Reference: CV2-5932.

app/models/team.rb

@@ -1,4 +1,6 @@
 class Team < ApplicationRecord
+  class RelevantArticlesError < StandardError; end
+
   # These two callbacks must be in the top
   after_create :create_team_partition
   before_destroy :delete_created_bots, :remove_is_default_project_flag
@@ -563,10 +565,14 @@ def filter_by_keywords(query, filters, type = 'FactCheck')
     query.where(Arel.sql("#{tsvector} @@ #{tsquery}"))
   end
 
+  def similar_articles_search_limit(pm = nil)
+    pm.nil? ? CheckConfig.get('most_relevant_team_limit', 3, :integer) : CheckConfig.get('most_relevant_item_limit', 10, :integer)
+  end
+
   def search_for_similar_articles(query, pm = nil)
     # query:  expected to be text
     # pm: to request a most relevant to specific item and also include both FactCheck & Explainer
-    limit = pm.nil? ? CheckConfig.get('most_relevant_team_limit', 3, :integer) : CheckConfig.get('most_relevant_item_limit', 10, :integer)
+    limit = self.similar_articles_search_limit(pm)
     threads = []
     fc_items = []
     ex_items = []
@@ -593,7 +599,12 @@ def search_for_similar_articles(query, pm = nil)
     items = fc_items
     # Get Explainers if no fact-check returned or get similar_articles for a ProjectMedia
     items += ex_items if items.blank? || !pm.nil?
+    Rails.logger.info("Relevant articles found for team slug #{self.slug}, project media with ID #{pm&.id} and query #{query}: #{items.map(&:graphql_id)}")
     items
+  rescue StandardError => e
+    Rails.logger.warn("Error when trying to retrieve relevant articles for team slug #{self.slug}, project media with ID #{pm&.id} and query #{query}.")
+    CheckSentry.notify(RelevantArticlesError.new('Error when trying to retrieve relevant articles'), team_slug: self.slug, project_media_id: pm&.id, query: query, exception_message: e.message, exception: e)
+    []
   end
 
   def get_shorten_outgoing_urls

test/models/team_2_test.rb

@@ -1583,4 +1583,11 @@ def setup
     end
     Bot::Smooch.unstub(:search_for_explainers)
   end
+
+  test "should notify Sentry if it fails to retrieve relevant articles" do
+    Bot::Smooch.stubs(:search_for_similar_published_fact_checks_no_cache).raises(StandardError)
+    CheckSentry.expects(:notify).once
+    t = create_team
+    assert_equal [], t.search_for_similar_articles('Test')
+  end
 end