Self-host email assets instead of relying on raw.githubusercontent.com

app/assets/images/email/README.md

@@ -0,0 +1,21 @@
+# Email Assets
+
+Images in this folder are used in transactional emails sent by the planner
+application. They are referenced via the Rails asset pipeline with digest
+fingerprinting.
+
+## ⚠️ Do not modify or delete existing files
+
+The digest fingerprint is derived from the file content. Changing an image
+here changes its URL. Any previously-sent email that references the old URL
+will show a broken image in the recipient's inbox.
+
+**Additive changes only.** Need a new image for a new email? Add a new file.
+Need a new logo? Add it as a new filename (e.g. `logo-2026.png`) and update
+the mailer view to reference the new file. Never mutate an existing file.
+
+## Email stylesheet
+
+The email CSS lives at `app/assets/stylesheets/email.css` — not in this
+folder — but it's referenced by mailer layouts via the pipeline path
+`email.css`.

app/views/shared_mailers/_body_header.html.haml

@@ -6,8 +6,7 @@
         %table{ bgcolor: "#fdfdfd" }
           %tr
             %td{ width: "40%" }
-              // TODO: maybe get this from codebar.io
-              = image_tag("https://raw.githubusercontent.com/codebar/assets/master/logo/png/website-logo.png", alt: "codebar logo")
+              = image_tag("email/website-logo.png", alt: "codebar logo")
             %td{ align: "right" }
               %h6.collapse= title
     %td

app/views/shared_mailers/_header.html.haml

@@ -6,4 +6,4 @@
   %meta{ 'http-equiv' => "Content-Type", content: "text/html; charset=UTF-8" }
   %title=title
 
-  %link{rel: "stylesheet", type: "text/css", href: "/assets/email.css"}
+  %link{rel: "stylesheet", type: "text/css", href: asset_path("email.css")}

config/environments/development.rb

@@ -43,6 +43,9 @@
   # Set localhost to be used by links generated in mailer templates.
   config.action_mailer.default_url_options = { host: "localhost", port: 3000 }
 
+  # Host for absolute asset URLs in emails (for local email preview).
+  config.action_mailer.asset_host = "http://localhost:3000"
+
   # Print deprecation notices to the Rails logger.
   config.active_support.deprecation = :log
 

config/environments/production.rb

@@ -68,6 +68,9 @@
   # Set host to be used by links generated in mailer templates.
   config.action_mailer.default_url_options = { host: 'codebar.io' }
 
+  # Host for absolute asset URLs in emails. Override for staging via ASSET_HOST env var.
+  config.action_mailer.asset_host = ENV.fetch('ASSET_HOST', 'https://codebar.io')
+
   # Specify outgoing SMTP server. Remember to add smtp/* credentials via rails credentials:edit.
   config.action_mailer.smtp_settings = {
      port: '587',