What's new

This release adds various improvements to many parts of the MTA. Notable changes include message priority support in the active queue to prioritize deliveries, as well as the ability to define custom thread pool for script execution and to set thread priorities to improve performance. Please see the changelog below for a full list of changes, and the release blog for more information.

Important changes

• Removed the following deprecated functions from the per-message end-of-DATA script. They were only available in one release (5.0). Queue(), GetMailMessage(), GetTLS(), GetAddressList(), DKIMSign(), DKIMSDID(), DKIMVerify()
  
• Removed ability to control rated or dlpd from halonctl. Use ratectl and dlpctl instead.
• Removed support for the per-recipient end-of-DATA script from the Linux builds. This change doesn't affect the integrated (VM) package.

Deprecation warnings

• Deprecated use of MIME("0") in end-of-DATA script by triggering a warning in the log. Use $arguments["mail"] or GetMailMessage() instead. Its use is discouraged and we'll change this deprecation to a critical error a few releases before it's removed to assist the migration.

Changelog

This is a list of notable changes. You can find the full changelog here.

Added

• MTA
  • Added priority for queued messages
  • Added max age of messages in queue (retry.during) as an alternative to retry.count
  • Added support for thread priority for various thread pools and event loops
  • Added support for more AUTH mechanisms in SMTP clients (eg. XOAUTH2)
  • Added queues.maxmessages to limit number of messages to hold in memory
  • Added data.fixheaders (false) and data.mimepart.fixheaders (false) to inject \r\n before bad headers
  • Added $arguments["expired"] to post-delivery hook to indicate bounces due to age or max retry count
• Scripting language
  • Added array dereference with spread operator inside of arrays
  • Allow upcast of TLSSocket to Socket with TLSocket.toSocket()
  • Added setFileName() and setDisposition() functions to MIME()
  • Added support to create MailMessages from File objects using MailMessage::File()
• Native plugins
  • Added support to get object properties with HalonMTA_hsl_object_property_get()
  • Create MailMessage and File classes from strings with HalonMTA_hsl_value_set()
  • Detect MailMessage type with HalonMTA_hsl_value_type()
• HTTP submission API
  • Added /health endpoints to be used with load balancers
  • Added $arguments["headers"] to end-of-DATA script