How to handle Postmark delivery errors (Postmark::InvalidMessageError) in Rails mailers
On Rails 5+, use ActionMailer's exception handling: ActionMailer::Base.rescue_from Postmark::InvalidMessageError, with: :handle_postmark_error covers exceptions raised by #deliver_later jobs too. On Rails 4.2 with deliver_later, patch the delivery job or rescue around the mailer call and report expected failures…
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