Devise + Bootstrap Email -- Throwing NoMethodError (undefined method + for nil:NilClass) from /bootstrap-email-1.4.1/lib/bootstrap-email/converters/head_style.rb:32:in 'purged_css_from_head'

[wwvuillemot]

Hi!

I'm trying to get Bootstrap Email to work with Devise emails.

Here's what I've done

app/initializers/devise.rb

 # Configure the class responsible to send e-mails.
  config.mailer = 'UserMailer'
  
  # Configure the parent class responsible to send e-mails.
  config.parent_mailer = 'ApplicationMailer'

app/mailers/user_mailer.rb

# frozen_string_literal: true

class UserMailer < Devise::Mailer
  layout 'bootstrap_mailer'
  default template_path: 'devise/mailer'

  def devise_mail(record, action, opts = {}, &block)
    initialize_from_record(record)
    bootstrap_mail headers_for(action, opts), &block
  end
end

app/mailers/application_mailer.rb

# frozen_string_literal: true

class ApplicationMailer < ActionMailer::Base
  default from: ENV.fetch('ADMIN_EMAIL')
  layout 'bootstrap_mailer'
end

app/stylesheets/bootstrap-head.scss

//- NOTHING

app/stylesheets/bootstrap-email.scss

//= @import bootstrap-email;

body,
.body {
  margin: 0;
  Margin: 0; // For compatibility with Outlook
  padding: 0;
  border: 0;
  outline: 0;

// a bunch more from the css reset

When I go to fire an email, Sidekiq is throwing the following:

ERROR: Error performing ActionMailer::MailDeliveryJob (Job ID: f371f6ca-cd13-49fa-bd09-6d6e6d0b22ef) from Sidekiq(mailers) in 157.49ms: NoMethodError (undefined method +' for nil:NilClass):`

Here is what I think are the relevant logs and stack trace.

024-04-17 11:43:19 2024-04-17T18:43:19.757Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a INFO: Performing ActionMailer::MailDeliveryJob (Job ID: f371f6ca-cd13-49fa-bd09-6d6e6d0b22ef) from Sidekiq(mailers) enqueued at 2024-04-17T18:41:04.977899800Z with arguments: "UserMailer", "reset_password_instructions", "deliver_now", {:args=>[#<GlobalID:0x0000ffff9c82cbb0 @uri=#<URI::GID gid:https://shai-web/User/ce6755b8-7ed0-4ae3-86f4-6404b5fdb156>>, "-4njdQsJJsx4tL3MyFAq", {}]}
2024-04-17 11:43:19 2024-04-17T18:43:19.758Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a DEBUG:   Rendering layout layouts/bootstrap_mailer.html.haml
2024-04-17 11:43:19 2024-04-17T18:43:19.759Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a DEBUG:   Rendering devise/mailer/reset_password_instructions.html.haml within layouts/bootstrap_mailer
2024-04-17 11:43:19 2024-04-17T18:43:19.759Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a INFO:   Rendered devise/mailer/reset_password_instructions.html.haml within layouts/bootstrap_mailer (Duration: 0.4ms | Allocations: 167)
2024-04-17 11:43:19 2024-04-17T18:43:19.759Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a INFO:   Rendered layout layouts/bootstrap_mailer.html.haml (Duration: 1.1ms | Allocations: 292)
2024-04-17 11:43:19 2024-04-17T18:43:19.912Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a DEBUG: UserMailer#reset_password_instructions: processed outbound mail in 154.8ms
2024-04-17 11:43:19 2024-04-17T18:43:19.913Z pid=8 tid=ja8 class=ActionMailer::MailDeliveryJob jid=4c08667e628b4483c253181a ERROR: Error performing ActionMailer::MailDeliveryJob (Job ID: f371f6ca-cd13-49fa-bd09-6d6e6d0b22ef) from Sidekiq(mailers) in 157.49ms: NoMethodError (undefined method `+' for nil:NilClass):
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/converters/head_style.rb:32:in `purged_css_from_head'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/converters/head_style.rb:16:in `bootstrap_email_head'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/converters/head_style.rb:8:in `build'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/converters/base.rb:14:in `build'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/compiler.rb:104:in `configure_html'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/compiler.rb:36:in `perform_html_compile'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/compiler.rb:24:in `perform_multipart_compile'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/rails/mail_builder.rb:50:in `generate_alternative_part'
2024-04-17 11:43:19 /usr/local/bundle/gems/bootstrap-email-1.4.1/lib/bootstrap-email/rails/mail_builder.rb:38:in `generate_html_part_replacement'

[wwvuillemot]

FWIW, I removed the bootstrap-head.scss and it worked.

I'm not really sure what the difference is with these two scss files are. But apparently if that exists and is empty it will throw the above error.

While its working, now I want to figure out how best to use those files -- any pointers?