Allow custom event timeseries in stats API (#3505)

* Allow custom event timeseries in stats API

* Fix linting error

---------

Co-authored-by: Uku Taht <Uku.taht@gmail.com>

CHANGELOG.md

@@ -38,6 +38,7 @@ All notable changes to this project will be documented in this file.
 - Update bot detection (matomo 6.1.4, ua_inspector 3.4.0)
 - Improved the Goal Settings page (search, autcompletion etc.)
 - Log mailer errors plausible/analytics#3336
+- Allow custom event timeseries in stats API plausible/analytics#3505
 
 ## v2.0.0 - 2023-07-12
 

lib/plausible/stats/timeseries.ex

@@ -15,7 +15,7 @@ defmodule Plausible.Stats.Timeseries do
   @typep value :: nil | integer() | float()
   @type results :: nonempty_list(%{required(:date) => Date.t(), required(metric()) => value()})
 
-  @event_metrics [:visitors, :pageviews, :average_revenue, :total_revenue]
+  @event_metrics [:visitors, :pageviews, :events, :average_revenue, :total_revenue]
   @session_metrics [:visits, :bounce_rate, :visit_duration, :views_per_visit]
   def timeseries(site, query, metrics) do
     steps = buckets(query)
@@ -218,10 +218,12 @@ defmodule Plausible.Stats.Timeseries do
     end
   end
 
+  # credo:disable-for-next-line Credo.Check.Refactor.CyclomaticComplexity
   defp empty_row(date, metrics) do
     Enum.reduce(metrics, %{date: date}, fn metric, row ->
       case metric do
         :pageviews -> Map.merge(row, %{pageviews: 0})
+        :events -> Map.merge(row, %{events: 0})
         :visitors -> Map.merge(row, %{visitors: 0})
         :visits -> Map.merge(row, %{visits: 0})
         :views_per_visit -> Map.merge(row, %{views_per_visit: 0.0})

test/plausible_web/controllers/api/external_stats_controller/timeseries_test.exs

@@ -846,6 +846,55 @@ defmodule PlausibleWeb.Api.ExternalStatsController.TimeseriesTest do
              }
     end
 
+    test "shows events for last 7d", %{conn: conn, site: site} do
+      populate_stats(site, [
+        build(:event, name: "Signup", timestamp: ~N[2021-01-01 00:00:00]),
+        build(:event, name: "Signup", timestamp: ~N[2021-01-01 00:00:00]),
+        build(:event, name: "Signup", timestamp: ~N[2021-01-07 23:59:00])
+      ])
+
+      conn =
+        get(conn, "/api/v1/stats/timeseries", %{
+          "site_id" => site.domain,
+          "period" => "7d",
+          "metrics" => "events",
+          "date" => "2021-01-07"
+        })
+
+      assert json_response(conn, 200) == %{
+               "results" => [
+                 %{
+                   "date" => "2021-01-01",
+                   "events" => 2
+                 },
+                 %{
+                   "date" => "2021-01-02",
+                   "events" => 0
+                 },
+                 %{
+                   "date" => "2021-01-03",
+                   "events" => 0
+                 },
+                 %{
+                   "date" => "2021-01-04",
+                   "events" => 0
+                 },
+                 %{
+                   "date" => "2021-01-05",
+                   "events" => 0
+                 },
+                 %{
+                   "date" => "2021-01-06",
+                   "events" => 0
+                 },
+                 %{
+                   "date" => "2021-01-07",
+                   "events" => 1
+                 }
+               ]
+             }
+    end
+
     test "rounds views_per_visit to two decimal places", %{
       conn: conn,
       site: site