From 1356228b05af05ef8b94e0a31f320a9fa11e6672 Mon Sep 17 00:00:00 2001
From: Nicolas Zermati <nicoolas25@gmail.com>
Date: Sun, 30 May 2021 09:53:48 +0200
Subject: [PATCH] Throttle inactive user emails

---
 app/mailers/user_mailer.rb                    | 11 +++++---
 app/models/user.rb                            |  1 +
 ...20_add_last_inactive_user_email_sent_at.rb |  5 ++++
 db/schema.rb                                  |  3 ++-
 spec/mailers/user_mailer_spec.rb              | 27 +++++++++++++++++++
 5 files changed, 43 insertions(+), 4 deletions(-)
 create mode 100644 db/migrate/20210530071920_add_last_inactive_user_email_sent_at.rb
 create mode 100644 spec/mailers/user_mailer_spec.rb

diff --git a/app/mailers/user_mailer.rb b/app/mailers/user_mailer.rb
index c5b453ec9..fcbe645ca 100644
--- a/app/mailers/user_mailer.rb
+++ b/app/mailers/user_mailer.rb
@@ -1,13 +1,18 @@
 class UserMailer < ApplicationMailer
   default from: "Covidliste <inscription@covidliste.com>"
 
+  MIN_SEND_INTERVAL = 7.days
+
   def send_inactive_user_unsubscription_request
-    user = User.find(params[:user_id])
+    @user = User.find(params[:user_id])
+
+    return if @user.email.blank?
+    return if @user.last_inactive_user_email_sent_at && @user.last_inactive_user_email_sent_at >= MIN_SEND_INTERVAL.ago
 
-    return if user.email.blank?
+    @user.touch(:last_inactive_user_email_sent_at)
 
     mail(
-      to: user.email,
+      to: @user.email,
       subject: "Attendez-vous toujours une dose de vaccin ?"
     )
   end
diff --git a/app/models/user.rb b/app/models/user.rb
index 3d688b08e..75e4706a5 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -156,6 +156,7 @@ def anonymize!
     self.birthdate = nil
     self.grid_i = nil
     self.grid_j = nil
+    self.last_inactive_user_email_sent_at = nil
     self.anonymized_at = Time.now.utc
     save(validate: false)
   end
diff --git a/db/migrate/20210530071920_add_last_inactive_user_email_sent_at.rb b/db/migrate/20210530071920_add_last_inactive_user_email_sent_at.rb
new file mode 100644
index 000000000..9e09688e5
--- /dev/null
+++ b/db/migrate/20210530071920_add_last_inactive_user_email_sent_at.rb
@@ -0,0 +1,5 @@
+class AddLastInactiveUserEmailSentAt < ActiveRecord::Migration[6.1]
+  def change
+    add_column :users, :last_inactive_user_email_sent_at, :datetime
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index f90ea274e..6c5b8e1ae 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2021_05_29_122300) do
+ActiveRecord::Schema.define(version: 2021_05_30_071920) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -297,6 +297,7 @@
     t.string "email_domain"
     t.integer "grid_i"
     t.integer "grid_j"
+    t.datetime "last_inactive_user_email_sent_at"
     t.index ["anonymized_at"], name: "index_users_on_anonymized_at"
     t.index ["birthdate"], name: "index_users_on_birthdate"
     t.index ["city"], name: "index_users_on_city"
diff --git a/spec/mailers/user_mailer_spec.rb b/spec/mailers/user_mailer_spec.rb
new file mode 100644
index 000000000..025423340
--- /dev/null
+++ b/spec/mailers/user_mailer_spec.rb
@@ -0,0 +1,27 @@
+require "rails_helper"
+
+RSpec.describe UserMailer, type: :mailer do
+  describe "#send_inactive_user_unsubscription_request" do
+    let(:mail) { described_class.with(user_id: user.id).send_inactive_user_unsubscription_request }
+    let(:user) { create(:user) }
+
+    it "renders the headers" do
+      expect(mail.subject).to eq("Attendez-vous toujours une dose de vaccin ?")
+      expect(mail.to).to eq([user.email])
+      expect(mail.from).to eq(["inscription@covidliste.com"])
+    end
+
+    it "updates the last_inactive_user_email_sent_at" do
+      expect { mail.deliver_now }
+        .to change { user.reload.last_inactive_user_email_sent_at }
+        .from(nil)
+        .to(be_within(1.minute).of(Time.zone.now))
+    end
+
+    it "includes a signed link to the confirm_destroy_profile URL" do
+      match_data = mail.body.encoded.match(%r{/users/profile/confirm_destroy\?authentication_token=([^"]+)"})
+      token = CGI.unescape(match_data.captures.first)
+      expect(User.find_signed(token, purpose: "users.destroy")).to eq(user)
+    end
+  end
+end