Add Handle* methods for compatibility with RT 4.4

Email plugin handling for RT 4.4 was refactored, providing
new HandleAction hooks rather than including all functionality
in GetCurrentUser. Create a new Action module and provide
Handle methods for the standard comment and correspond actions
to allow users to upgrade in place.

The updates allow the code to run for both RT 4.2 and
4.4 with minimal duplication. However the code is in a new
module, so users will need to update their RT_SiteConfig.pm.

etc/handle_action_pass_currentuser.patch

@@ -0,0 +1,12 @@
+diff --git a/lib/RT/Interface/Email.pm b/lib/RT/Interface/Email.pm
+index 175805d..7ffba8e 100644
+--- a/lib/RT/Interface/Email.pm
++++ b/lib/RT/Interface/Email.pm
+@@ -248,6 +248,7 @@ sub Gateway {
+             Action      => $action,
+             Subject     => $Subject,
+             Message     => $Message,
++            CurrentUser => $CurrentUser,
+             Ticket      => $Ticket,
+             TicketId    => $args{ticket},
+             Queue       => $SystemQueueObj,

lib/RT/Extension/CommandByMail.pm

@@ -57,8 +57,24 @@ C<@MailPlugins> configuration, as follows:
 
     Set(@MailPlugins, qw(Auth::MailFrom Filter::TakeAction));
 
+For RT 4.4 or newer, the plugin code is in C<Action::CommandByMail>, so
+add this:
+
+    Set(@MailPlugins, qw(Auth::MailFrom Action::CommandByMail));
+
 Be sure to include C<Auth::MailFrom> in the list as well.
 
+B<Note:> The plugin name has changed for RT 4.4, so after upgrading you
+must also update your C<RT_SiteConfig.pm> file to change
+C<Filter::TakeAction> to the new C<Action::CommandByMail>.
+
+=item Patch RT
+
+For RT 4.4.0, apply the included patch:
+
+    cd /opt/rt4  # Your location may be different
+    patch -p1 < /download/dir/RT-Extension-CommandByMail/etc/handle_action_pass_currentuser.patch
+
 =item Restart your webserver
 
 =back
@@ -225,6 +241,14 @@ If set, the body will not be examined, only the headers.
 
 This extension is incompatible with C<UnsafeEmailCommands> RT option.
 
+=head1 METHODS
+
+=head2 ProcessCommands
+
+This method provides the main email processing functionality. It supports
+both RT 4.2 and earlier and 4.4 and later. To do this, the return hashes
+contain some values used by 4.2 code and some used by 4.4. The return
+values coexist and unused values are ignored by the different versions.
 =cut
 
 sub ProcessCommands {
@@ -245,11 +269,19 @@ sub ProcessCommands {
             ."CurrentUser (actor) is not authorized. "
         );
         return { CurrentUser => $args{'CurrentUser'},
-                 AuthLevel   => $args{'AuthLevel'} };
+                 AuthLevel   => $args{'AuthLevel'},
+                 MailError   => 1,
+                 ErrorSubject     => "Permission Denied",
+                 Explanation => "CurrentUser is not set when trying to "
+                 . "process email command via CommandByMail",
+                 Failure     => 1
+             };
     }
 
+    $RT::Logger->debug("Running CommandByMail as ".$args{'CurrentUser'}->UserObj->Name);
+
     # If the user isn't asking for a comment or a correspond,
-    # bail out
+    # bail out. Only relevant for pre-4.2.
     unless ( $args{'Action'} =~ /^(?:comment|correspond)$/i ) {
         return { CurrentUser => $args{'CurrentUser'},
                  AuthLevel   => $args{'AuthLevel'} };
@@ -269,12 +301,16 @@ sub ProcessCommands {
         if (!$group->HasMemberRecursively($args{'CurrentUser'}->PrincipalObj)) {
             $RT::Logger->debug("CurrentUser not in CommandByMailGroup");
             return { CurrentUser => $args{'CurrentUser'},
-                     AuthLevel   => $args{'AuthLevel'} };
+                     AuthLevel   => $args{'AuthLevel'},
+                     MailError   => 1,
+                     ErrorSubject     => "Permission Denied",
+                     Explanation => "User " . $args{'CurrentUser'}->UserObj->EmailAddress
+                     . " is not in the configured CommandByMailGroup",
+                     Failure     => 1
+                 };
         }
     }
 
-    $RT::Logger->debug("Running CommandByMail as ".$args{'CurrentUser'}->UserObj->Name);
-
     my $headername = $new_config
         ? RT->Config->Get('CommandByMailHeader')
         : $RT::CommandByMailHeader;
@@ -459,7 +495,13 @@ sub ProcessCommands {
                     "Couldn't write $args{'Action'}."
                     ." Fallback to standard mailgate. Error: $msg");
                 return { CurrentUser => $args{'CurrentUser'},
-                         AuthLevel   => $args{'AuthLevel'} };
+                         AuthLevel   => $args{'AuthLevel'},
+                         MailError   => 1,
+                         ErrorSubject     => "Unable to execute $args{'Action'}",
+                         Explanation => "Unable to execute $args{'Action'} on ticket "
+                         . $args{'Ticket'}->Id . ": $msg",
+                         Failure     => 1
+                     };
             }
         }
 
@@ -853,7 +895,6 @@ sub _ReportResults {
 }
 
 
-
 1;
 __END__
 

lib/RT/Interface/Email/Action/CommandByMail.pm

@@ -0,0 +1,56 @@
+package RT::Interface::Email::Action::CommandByMail;
+
+use warnings;
+use strict;
+
+use Role::Basic 'with';
+with 'RT::Interface::Email::Role';
+
+=head1 NAME
+
+RT::Interface::Email::Action::CommandByMail - Change metadata of ticket via email
+
+=head1 DESCRIPTION
+
+This action provides compatibility with the new mail plugin system introduced
+in RT 4.4. It provides an alternate to the default comment and correspond
+handlers provided by RT.
+
+=cut
+
+# To maintain compatibility with previous versions of CommandByMail,
+# handle the standard comment and correspond actions. Follow the
+# pattern from RT's default action handling for providing both.
+
+sub HandleComment {
+    _HandleEither( @_, Action => "Comment" );
+}
+
+sub HandleCorrespond {
+    _HandleEither( @_, Action => "Correspond" );
+}
+
+sub _HandleEither {
+    my %args = (
+        Action      => undef,
+        Message     => undef,
+        Subject     => undef,
+        Ticket      => undef,
+        TicketId    => undef,
+        Queue       => undef,
+        @_,
+    );
+
+    my $return_ref = RT::Extension::CommandByMail::ProcessCommands(%args);
+
+    if ( exists $return_ref->{'MailError'} and $return_ref->{'MailError'} ){
+        MailError(
+            Subject     => $return_ref->{'ErrorSubject'},
+            Explanation => $return_ref->{'Explanation'},
+            FAILURE     => $return_ref->{'Failure'},
+        );
+    }
+    return;
+}
+
+1;