chore: Remove stale contact presence records (#5205)

fixes: chatwoot/product#493

lib/online_status_tracker.rb

@@ -39,7 +39,11 @@ module OnlineStatusTracker
   end
 
   def self.get_available_contact_ids(account_id)
-    ::Redis::Alfred.zrangebyscore(presence_key(account_id, 'Contact'), (Time.zone.now - PRESENCE_DURATION).to_i, Time.now.to_i)
+    range_start = (Time.zone.now - PRESENCE_DURATION).to_i
+    # exclusive minimum score is specified by prefixing (
+    # we are clearing old records because this could clogg up the sorted set
+    ::Redis::Alfred.zremrangebyscore(presence_key(account_id, 'Contact'), '-inf', "(#{range_start}")
+    ::Redis::Alfred.zrangebyscore(presence_key(account_id, 'Contact'), range_start, '+inf')
   end
 
   def self.get_available_contacts(account_id)
@@ -58,9 +62,8 @@ module OnlineStatusTracker
 
   def self.get_available_user_ids(account_id)
     account = Account.find(account_id)
-    # TODO: to migrate this to zrange as its is being deprecated
+    range_start = (Time.zone.now - PRESENCE_DURATION).to_i
-    # https://redis.io/commands/zrangebyscore/
+    user_ids = ::Redis::Alfred.zrangebyscore(presence_key(account_id, 'User'), range_start, '+inf')
-    user_ids = ::Redis::Alfred.zrangebyscore(presence_key(account_id, 'User'), (Time.zone.now - PRESENCE_DURATION).to_i, Time.now.to_i)
     # since we are dealing with redis items as string, casting to string
     user_ids += account.account_users.where(auto_offline: false)&.map(&:user_id)&.map(&:to_s)
     user_ids.uniq

lib/redis/alfred.rb

@@ -89,5 +89,11 @@ module Redis::Alfred
     def zrangebyscore(key, range_start, range_end)
       $alfred.zrangebyscore(key, range_start, range_end)
     end
+
+    # remove values by score
+    # exclusive score is specified by prefixing (
+    def zremrangebyscore(key, range_start, range_end)
+      $alfred.zremrangebyscore(key, range_start, range_end)
+    end
   end
 end

spec/lib/online_status_tracker_spec.rb

@@ -21,4 +21,25 @@ describe OnlineStatusTracker do
       expect(described_class.get_available_users(account.id).keys).to contain_exactly(user1.id.to_s, user2.id.to_s)
     end
   end
+
+  context 'when get_available_contacts' do
+    let(:online_contact) { create(:contact, account: account) }
+    let(:offline_contact) { create(:contact, account: account) }
+
+    before do
+      described_class.update_presence(account.id, 'Contact', online_contact.id)
+      # creating a stale record for offline contact presence
+      ::Redis::Alfred.zadd(format(::Redis::Alfred::ONLINE_PRESENCE_CONTACTS, account_id: account.id),
+                           (Time.zone.now - (OnlineStatusTracker::PRESENCE_DURATION + 20)).to_i, offline_contact.id)
+    end
+
+    it 'returns only the online contact ids with presence' do
+      expect(described_class.get_available_contacts(account.id).keys).to contain_exactly(online_contact.id.to_s)
+    end
+
+    it 'flushes the stale records from sorted set after the duration' do
+      described_class.get_available_contacts(account.id)
+      expect(::Redis::Alfred.zscore(format(::Redis::Alfred::ONLINE_PRESENCE_CONTACTS, account_id: account.id), offline_contact.id)).to be_nil
+    end
+  end
 end