From 3d105fcfdbaacd5dcfd357859ac48b97dfec113b Mon Sep 17 00:00:00 2001
From: Matthew Landauer <mlandauer@gmail.com>
Date: Wed, 31 Jan 2024 06:44:07 +0000
Subject: [PATCH] Keep gmail happy by allowing one click post unsubscribe

---
 app/mailers/alert_mailer.rb       | 4 ++--
 config/routes.rb                  | 1 +
 spec/mailers/alert_mailer_spec.rb | 1 +
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/app/mailers/alert_mailer.rb b/app/mailers/alert_mailer.rb
index fd4dfc6df..4924b7495 100644
--- a/app/mailers/alert_mailer.rb
+++ b/app/mailers/alert_mailer.rb
@@ -19,8 +19,8 @@ def alert(alert:, applications: [], comments: [])
     @comments = T.let(comments, T.nilable(T::Array[Comment]))
 
     headers(
-      # The List-Unsubscribe header appears not to be working in gmail anymore
-      # TODO: Figure out what's going on. Is it fixable?
+      # The unsubscribe URL needs to accept a post
+      "List-Unsubscribe-Post" => "List-Unsubscribe=One-Click",
       "List-Unsubscribe" => "<#{unsubscribe_alert_url(confirm_id: alert.confirm_id)}>",
       # This special header sets arbitrary metadata on the email in Cuttlefish
       # It's not sent on in the outgoing email
diff --git a/config/routes.rb b/config/routes.rb
index 3ae63846f..03b7c19fd 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -96,6 +96,7 @@ def matches?(request)
   resources :alerts, only: %i[new create], path_names: { new: "signup" }, param: :confirm_id do
     member do
       get :unsubscribe
+      post :unsubscribe
     end
   end
 
diff --git a/spec/mailers/alert_mailer_spec.rb b/spec/mailers/alert_mailer_spec.rb
index 9699177f9..3c8e52d5a 100644
--- a/spec/mailers/alert_mailer_spec.rb
+++ b/spec/mailers/alert_mailer_spec.rb
@@ -56,6 +56,7 @@
 
     it "has the unsubscribe header" do
       expect(email.header["List-Unsubscribe"].to_s).to eq("<https://dev.planningalerts.org.au/alerts/abcdef/unsubscribe>")
+      expect(email.header["List-Unsubscribe-Post"].to_s).to eq("List-Unsubscribe=One-Click")
     end
   end