Bugfix: Allow breakdown by internally used prop keys for Growth plans (#3562)

* fix bug - allow internally used prop key breakdown for Growth plans

* use case instead of with

lib/plausible/props.ex

@@ -96,6 +96,14 @@ defmodule Plausible.Props do
   """
   def internal_keys, do: @internal_keys
 
+  def ensure_prop_key_accessible(prop_key, user) do
+    if prop_key in @internal_keys do
+      :ok
+    else
+      Plausible.Billing.Feature.Props.check_availability(user)
+    end
+  end
+
   @spec suggest_keys_to_allow(Plausible.Site.t(), non_neg_integer()) :: [String.t()]
   @doc """
   Queries the events table to fetch the #{@max_props} most frequent prop keys

lib/plausible_web/controllers/api/stats_controller.ex

@@ -1185,8 +1185,9 @@ defmodule PlausibleWeb.Api.StatsController do
 
   def custom_prop_values(conn, params) do
     site = Plausible.Repo.preload(conn.assigns.site, :owner)
+    prop_key = Map.fetch!(params, "prop_key")
 
-    case Plausible.Billing.Feature.Props.check_availability(site.owner) do
+    case Plausible.Props.ensure_prop_key_accessible(prop_key, site.owner) do
       :ok ->
         props = breakdown_custom_prop_values(site, params)
         json(conn, props)

test/plausible_web/controllers/api/stats_controller/custom_prop_breakdown_test.exs

@@ -177,17 +177,6 @@ defmodule PlausibleWeb.Api.StatsController.CustomPropBreakdownTest do
                }
              ]
     end
-
-    test "errors when site owner is on a growth plan", %{conn: conn, site: site, user: user} do
-      insert(:growth_subscription, user: user)
-
-      conn = get(conn, "/api/stats/#{site.domain}/custom-prop-values/prop?period=day")
-
-      assert json_response(conn, 402) == %{
-               "error" =>
-                 "Custom Properties is part of the Plausible Business plan. To get access to this feature, please upgrade your account."
-             }
-    end
   end
 
   describe "GET /api/stats/:domain/custom-prop-values/:prop_key - with goal filter" do
@@ -1058,4 +1047,42 @@ defmodule PlausibleWeb.Api.StatsController.CustomPropBreakdownTest do
              ]
     end
   end
+
+  describe "GET /api/stats/:domain/custom-prop-values/:prop_key - for a Growth subscription" do
+    setup [:create_user, :log_in, :create_new_site]
+
+    setup %{user: user, site: site} do
+      insert(:growth_subscription, user: user)
+
+      populate_stats(site, [
+        build(:pageview,
+          "meta.key": ["url", "path", "author"],
+          "meta.value": ["one", "two", "three"]
+        )
+      ])
+
+      :ok
+    end
+
+    test "returns breakdown for internally used prop keys", %{conn: conn, site: site} do
+      [%{"visitors" => 1, "name" => "one"}] =
+        conn
+        |> get("/api/stats/#{site.domain}/custom-prop-values/url?period=day")
+        |> json_response(200)
+
+      [%{"visitors" => 1, "name" => "two"}] =
+        conn
+        |> get("/api/stats/#{site.domain}/custom-prop-values/path?period=day")
+        |> json_response(200)
+    end
+
+    test "returns 402 'upgrade required' for any other prop key", %{conn: conn, site: site} do
+      conn = get(conn, "/api/stats/#{site.domain}/custom-prop-values/prop?period=day")
+
+      assert json_response(conn, 402) == %{
+               "error" =>
+                 "Custom Properties is part of the Plausible Business plan. To get access to this feature, please upgrade your account."
+             }
+    end
+  end
 end