Explaining content merge and validation in mass-mailing: content processor in Arnica EmailServer

August 25, 2014 by Igor Lozhkin
Arnica EmailServer engages a content processor when evaluating each email template in the context of each user from the recipient pool when sending mass-mailing. Content processor is associated with an email template. EmailServer may have multiple content processors; email templates may share the same content processor.

Content processor defines rules and executes certain actions against email template at the time when the EmailServer processes the template in the context of a specific user. Content processor may change content of an email based on user properties, or even stop the email from being sent to the recipient.

The following is a list of features which may be engaged by content processor (based on setting of corresponding content processor property, which appears in the content processor properties page screenshot below).
  • Analyze email template for evaluatable expressions and optionally remove expressions. This is a useful feature to prevent not-trusted email template sources to inject active evaluatable expressions into the template content
  • Replace pre-defined (safe) custom expressions with evaluatable expressions. This feature may be used if there is a set of standard expressions permitted to appear in email template from not-trusted sources
  • Evaluate expressions in email template
  • Validate email address syntax and/or domain
  • Prepare extended user properties and global parameters to be referenced in evaluatable expressions
  • Engage content processor script, which may further analyze or change email template using any other logic, or stop the email from being sent to the recipient
  • Add message headers
  • Add mandatory begin and end content (before and after email template content, accordingly). This may be useful when managing such features as adding standard headers, open-rate tracking links, standard un-subscribe content and links, etc.