UPGRADING-4.2

UPGRADING FROM RT 4.0.0 and greater

* The $UseSQLForACLChecks option defaults to on.  This provides a number
  of improvements, most notably no longer showing pages of empty results
  if the user doesn't have permissions to view the tickets in question.
  It may, in some cases, have performance impacts, but these have been
  found to be minimal in existing 4.0 installs.

* The $LogToScreen config setting is now named $LogToSTDERR which better
  describes what the log level controls.  Setting $LogToScreen will still work,
  but an informational notice will be issued on server start telling you about
  the rename.  To avoid this you should set $LogToSTDERR instead.

* The link direction and type maps are consolidated into RT::Link.  If you
  wrote local customizations or extensions utilizing %RT::Ticket::LINKDIRMAP,
  %RT::Ticket::LINKTYPEMAP, RT::Ticket->LINKDIRMAP, RT::Ticket->LINKTYPEMAP, or
  %RT::Record::LINKDIRMAP, you will need to switch to %RT::Link::DIRMAP and
  %RT::Link::TYPEMAP.

* $LinkTransactionsRun1Scrip is removed.  If you were relying on this behaviour
  (by setting it to 1), you should adjust your scrips to ignore one of the link
  transactions.

* The $AttachmentUnits option was removed in preference of always displaying in
  megabytes, kilobytes, or bytes as appropriate.  The option was incompletely
  implemented and controlled display in the attachments list but not history.

* MakeClicky handlers added via a callback are now passed an "object" key in
  the parameter hash instead of "ticket".  The object may be any RT::Record
  subclass.

* $MessageBoxWrap was removed.  Wrapping is now always SOFT.  If you want hard
  line breaks, enter them manually.

* ShowUser handlers (/Elements/ShowUser*) have moved out of Mason components
  and into RT::User methods.  Any custom username formats will need to be
  reimplemented as RT::User methods.  Renaming should follow that of the core
  components:

        /Elements/ShowUserConcise => RT::User->_FormatUserConcise
        /Elements/ShowUserVerbose => RT::User->_FormatUserVerbose

  The _FormatUser* methods are passed a hash containing the keys User and
  Address, which have the same properties as before.

* Rich text (HTML) messages are now preferred for display.  If you prefer plain
  text messages, set $PreferRichText to 0.

* User email addresses are now validated by default and multiple,
  comma-separated addresses for a single user are no longer allowed.  Existing
  users with invalid addresses will continue to work until the next time they
  are updated by an administrator on the modify user page.  If you prefer no
  address validation, set $ValidateUserEmailAddresses to 0.

* The 'smtp' value for $MailCommand, along with the associated
  $SMTPServer, $SMTPFrom, and $SMTPDebug options, has been removed
  because it did not guarantee delivery.  Instead, use a local MTA for
  outgoing mail, via the 'sendmailpipe' setting to $MailCommand.

* The @JSFiles config now only keeps additional JavaScript filenames; if
  you had copied @JSFiles to add extra entries in your RT_SiteConfig,
  remove the core JS from the list, or RT will serve those files
  multiple times.

* The $DeferTransactionLoading was combined into the new option $ShowHistory.
  If you had enabled $DeferTransactionLoading, you may want to set $ShowHistory
  to "click".  However, $ShowHistory provides a new mode, "delay", which is the
  default and may be a more appealing alternative to "click".

* A Status transaction is now recorded when a ticket status changes as a
  result of a queue change.  Scrips with conditions relying on Status changes
  may start to trigger on these transitions; previously these Status changes
  never triggered scrips.

* The Googleish search has been renamed to Simple. If you were
  using this in an rt-crontool cronjob or had used a
  Googleish_Local.pm to add features, you will need to convert to
  using RT::Search::Simple instead.

* The Owner drop-down now only includes privileged users (no matter if
  unprivileged users have been granted the OwnTicket right) because
  configurations which have unprivileged Owners are exceedingly rare,
  and granting Everyone the OwnTicket right is a common cause of
  performance problems.  Unprivileged Owners (if they exist) may still
  be set using the Autocompleter.