feat: use stop to route cache in alerts filter expansion

config/test.exs

@@ -26,6 +26,7 @@ config :screens,
   blue_bikes_station_information_url: [:no_api_requests_allowed_during_testing],
   blue_bikes_station_status_url: [:no_api_requests_allowed_during_testing],
   blue_bikes_api_client: Screens.BlueBikes.FakeClient,
+  stops_to_routes_enabled: false,
   dup_headsign_replacements: %{
     "Test 1" => "T1"
   },

lib/screens/alerts/cache/filter.ex

@@ -2,7 +2,7 @@ defmodule Screens.Alerts.Cache.Filter do
   @moduledoc """
   Logic to apply filters to a list of `Screens.Alerts.Alert` structs.
   """
-  alias Screens.Stops.Stop
+  alias Screens.Stops.StopsToRoutes
 
   @default_activities ~w[BOARD EXIT RIDE]
 
@@ -87,10 +87,10 @@ defmodule Screens.Alerts.Cache.Filter do
   end
 
   defp build_matcher({:stops, values}, acc) when is_list(values) do
-    {:ok, routes} = stop_mod().fetch_routes_for_stops(values)
+    route_ids = StopsToRoutes.stops_to_routes(values)
 
     route_matchers =
-      for %{id: route_id} <- routes,
+      for route_id <- route_ids,
           stop_id <- [nil | values] do
         %{route: route_id, stop: stop_id}
       end
@@ -126,8 +126,4 @@ defmodule Screens.Alerts.Cache.Filter do
   defp matches?(alert, {key, value}) do
     Enum.any?(alert.informed_entities, &(Map.get(&1, key) == value))
   end
-
-  defp stop_mod do
-    Application.get_env(:screens, :alerts_cache_filter_stops_mod, Stop)
-  end
 end

lib/screens/stops/stops_to_routes.ex

@@ -11,7 +11,7 @@ defmodule Screens.Stops.StopsToRoutes do
 
   @spec stops_to_routes([stop_id :: String.t()]) :: [route_id :: String.t()]
   def stops_to_routes(stop_ids) do
-    from_cache = get_all(stop_ids)
+    from_cache = if enabled?(), do: get_all(stop_ids), else: %{}
     missing_stop_ids = stop_ids -- Map.keys(from_cache)
 
     from_api =
@@ -54,4 +54,8 @@ defmodule Screens.Stops.StopsToRoutes do
     additional_minutes = :rand.uniform(30)
     @base_ttl + :timer.minutes(additional_minutes)
   end
+
+  defp enabled? do
+    Application.get_env(:screens, :stops_to_routes_enabled, true)
+  end
 end

test/screens/alerts/alert_test.exs

@@ -113,11 +113,11 @@ defmodule Screens.Alerts.AlertTest do
 
   describe "fetch_from_cache/2" do
     setup do
-      default_stops_mod = Application.get_env(:screens, :alerts_cache_filter_stops_mod)
-      Application.put_env(:screens, :alerts_cache_filter_stops_mod, Stop.Mock)
+      default_stops_mod = Application.get_env(:screens, :stops_to_routes_stop_mod)
+      Application.put_env(:screens, :stops_to_routes_stop_mod, Stop.Mock)
 
       on_exit(fn ->
-        Application.put_env(:screens, :alerts_cache_filter_stops_mod, default_stops_mod)
+        Application.put_env(:screens, :stops_to_routes_stop_mod, default_stops_mod)
       end)
 
       alerts = [

test/screens/alerts/cache/filter_test.exs

@@ -9,11 +9,11 @@ defmodule Screens.Alerts.Cache.FilterTest do
 
   describe "build_matchers/1" do
     setup do
-      default_stops_mod = Application.get_env(:screens, :alerts_cache_filter_stops_mod)
-      Application.put_env(:screens, :alerts_cache_filter_stops_mod, Stop.Mock)
+      default_stops_mod = Application.get_env(:screens, :stops_to_routes_stop_mod)
+      Application.put_env(:screens, :stops_to_routes_stop_mod, Stop.Mock)
 
       on_exit(fn ->
-        Application.put_env(:screens, :alerts_cache_filter_stops_mod, default_stops_mod)
+        Application.put_env(:screens, :stops_to_routes_stop_mod, default_stops_mod)
       end)
     end
 
@@ -51,7 +51,7 @@ defmodule Screens.Alerts.Cache.FilterTest do
 
     test "adds matchers for routes at the stops" do
       stub(Stop.Mock, :fetch_routes_for_stops, fn
-        ["place-aport"] ->
+        "place-aport" ->
           {:ok, [%Route{id: "Blue"}, %Route{id: "743"}]}
       end)