Remove canonical-rails gem and handroll our own

Gemfile

@@ -20,9 +20,6 @@ gem 'puma', '~> 6.5'
 # Reduces boot times through caching; required in config/boot.rb
 gem 'bootsnap', '>= 1.1.0', require: false
 
-# Canonical meta tag
-gem 'canonical-rails'
-
 # Decorate logic to keep it out of the views and helper methods
 gem 'draper'
 

Gemfile.lock

@@ -177,8 +177,6 @@ GEM
       activesupport (>= 3.0.0)
       uniform_notifier (~> 1.11)
     byebug (11.1.3)
-    canonical-rails (0.2.16)
-      actionview (>= 4.1, < 7.3)
     capybara (3.40.0)
       addressable
       matrix
@@ -756,7 +754,6 @@ DEPENDENCIES
   brakeman
   bullet
   byebug
-  canonical-rails
   capybara (>= 2.15)
   cloudfront-rails
   colorize

app/views/layouts/application.html.erb

@@ -4,7 +4,10 @@
     <title><%= yield :page_title %> - Publish teacher training courses - GOV.UK</title>
     <%= csrf_meta_tags %>
     <%= csp_meta_tag %>
-    <%= canonical_tag %>
+
+    <% url = URI(request.url.split("?").first) %>
+    <%= tag.link(href: url.path.ends_with?("/") ? url.to_s : "#{url}/", rel: "canonical") %>
+    <%= tag.meta(property: "og:url", content: url.path.ends_with?("/") ? url.to_s : "#{url}/") %>
 
     <%= tag.meta(name: "viewport", content: "width=device-width, initial-scale=1") %>
     <%= tag.meta(property: "og:image", content: image_path("govuk-opengraph-image.png")) %>

app/views/layouts/find_layout.html.erb

@@ -4,7 +4,10 @@
     <title><%= yield :page_title %> - <%= t("service_name.find") %> - GOV.UK</title>
     <%= csrf_meta_tags %>
     <%= csp_meta_tag %>
-    <%= canonical_tag %>
+
+    <% url = URI(request.url.split("?").first) %>
+    <%= tag.link(href: url.path.ends_with?("/") ? url.to_s : "#{url}/", rel: "canonical") %>
+    <%= tag.meta(property: "og:url", content: url.path.ends_with?("/") ? url.to_s : "#{url}/") %>
 
     <%= tag.meta(name: "viewport", content: "width=device-width, initial-scale=1") %>
     <%= tag.meta(property: "og:image", content: image_path("govuk-opengraph-image.png")) %>