Fix annual notification loop

lib/workers/notify_annual_renewal.ex

@@ -19,6 +19,12 @@ defmodule Plausible.Workers.NotifyAnnualRenewal do
         }
       )
 
+    sent_notification =
+      from(
+        s in "sent_renewal_notifications",
+        where: s.timestamp > fragment("now() - INTERVAL '1 month'")
+      )
+
     users =
       Repo.all(
         from u in Plausible.Auth.User,
@@ -26,13 +32,13 @@ defmodule Plausible.Workers.NotifyAnnualRenewal do
           on: cs.user_id == u.id,
           join: s in Plausible.Billing.Subscription,
           on: s.inserted_at == cs.inserted_at,
-          left_join: sent in "sent_renewal_notifications",
+          left_join: sent in ^sent_notification,
           on: s.user_id == sent.user_id,
+          where: is_nil(sent.id),
           where: s.paddle_plan_id in @yearly_plans,
           where:
             s.next_bill_date > fragment("now()::date") and
               s.next_bill_date <= fragment("now()::date + INTERVAL '7 days'"),
-          where: is_nil(sent.id) or sent.timestamp < fragment("now() - INTERVAL '1 month'"),
           preload: [subscription: s]
       )
 

test/workers/notify_annual_renewal_test.exs

@@ -136,6 +136,32 @@ defmodule Plausible.Workers.NotifyAnnualRenewalTest do
     )
   end
 
+  test "does not send multiple notifications on second year", %{user: user} do
+    insert(:subscription,
+      user: user,
+      paddle_plan_id: @yearly_plan,
+      next_bill_date: Timex.shift(Timex.today(), days: 7)
+    )
+
+    Repo.insert_all("sent_renewal_notifications", [
+      %{
+        user_id: user.id,
+        timestamp: Timex.shift(Timex.today(), years: -1) |> Timex.to_naive_datetime()
+      }
+    ])
+
+    NotifyAnnualRenewal.perform(nil)
+
+    assert_email_delivered_with(
+      to: [{user.name, user.email}],
+      subject: "Your Plausible subscription is up for renewal"
+    )
+
+    NotifyAnnualRenewal.perform(nil)
+
+    assert_no_emails_delivered()
+  end
+
   test "sends renewal notification to user on v2 yearly pricing plans", %{
     user: user
   } do