performance refactor for group to users

Author: dbattersby

lib/discourse_data_explorer/report_generator.rb

@@ -127,11 +127,26 @@ def self.filter_recipients_by_query_access(recipients, query, users_from_group:
 
       query_group_ids = [Group::AUTO_GROUPS[:admins]].concat(query.groups.pluck(:group_id)).uniq
 
-      groups.each do |group|
-        if users_from_group
-          users = (users + group.users).uniq
-        elsif query_group_ids.include?(group.id)
-          result << [group.name, "group_name"]
+      if users_from_group
+        result.concat(
+          User
+            .joins(:group_users)
+            .where(group_users: { group_id: groups.ids })
+            .where(
+              "users.admin OR EXISTS (
+                SELECT 1 FROM group_users gu
+                WHERE gu.user_id = users.id
+                AND gu.group_id IN (?)
+              )",
+              query_group_ids,
+            )
+            .distinct
+            .pluck(:username)
+            .map { |username| [username, "username"] },
+        )
+      else
+        groups.each do |group|
+          result << [group.name, "group_name"] if query_group_ids.include?(group.id)
         end
       end
 

spec/report_generator_spec.rb

@@ -182,11 +182,9 @@
       describe "when true" do
         let(:opts) { { users_from_group: true } }
 
-        it "works with no query groups" do
+        it "does not work when no query groups are set" do
           result = described_class.generate(query.id, query_params, [group.name], opts)
-
-          expect(result.length).to eq(1)
-          expect(result[0]["target_usernames"]).to eq([user.username])
+          expect(result).to eq []
         end
 
         it "works when user is a member of automation group and query group" do