Bug 173622 - Move template handling into a module. r=justdave, joel, a=justdave

1 files changed, 192 insertions, 0 deletions

diff --git a/Bugzilla.pm b/Bugzilla.pm
new file mode 100644
index 000000000..f093edaa5
--- /dev/null
+++ b/Bugzilla.pm
@@ -0,0 +1,192 @@
+# -*- Mode: perl; indent-tabs-mode: nil -*-
+#
+# The contents of this file are subject to the Mozilla Public
+# License Version 1.1 (the "License"); you may not use this file
+# except in compliance with the License. You may obtain a copy of
+# the License at http://www.mozilla.org/MPL/
+#
+# Software distributed under the License is distributed on an "AS
+# IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+# implied. See the License for the specific language governing
+# rights and limitations under the License.
+#
+# The Original Code is the Bugzilla Bug Tracking System.
+#
+# The Initial Developer of the Original Code is Netscape Communications
+# Corporation. Portions created by Netscape are
+# Copyright (C) 1998 Netscape Communications Corporation. All
+# Rights Reserved.
+#
+# Contributor(s): Bradley Baetz <bbaetz@student.usyd.edu.au>
+#
+
+package Bugzilla;
+
+use strict;
+
+use Bugzilla::CGI;
+use Bugzilla::Template;
+
+sub create {
+    my $class = shift;
+    my $B = $class->instance;
+
+    # And set up the vars for this request
+    $B->_init_transient;
+
+    return $B;
+}
+
+# We don't use Class::Singleton, because theres no need. However, I'm keeping
+# the same interface in case we do change in the future
+
+my $_instance;
+sub instance {
+    my $class = shift;
+
+    $_instance = $class->_new_instance unless ($_instance);
+
+    return $_instance;
+}
+
+sub template { return $_[0]->{_template}; }
+sub cgi { return $_[0]->{_cgi}; }
+
+# PRIVATE methods below here
+
+# Called from instance
+sub _new_instance {
+    my $class = shift;
+
+    my $self = { };
+    bless($self, $class);
+
+    $self->_init_persistent;
+
+    return $self;
+}
+
+# Initialise persistent items
+sub _init_persistent {
+    my $self = shift;
+
+    # Set up the template
+    $self->{_template} = Bugzilla::Template->create();
+}
+
+# Initialise transient (per-request) items
+sub _init_transient {
+    my $self = shift;
+
+    $self->{_cgi} = new Bugzilla::CGI if exists $::ENV{'GATEWAY_INTERFACE'};
+}
+
+# Clean up transient items such as database handles
+sub _cleanup {
+    my $self = shift;
+
+    delete $self->{_cgi};
+}
+
+sub DESTROY {
+    my $self = shift;
+
+    # Clean up transient items. We can't just let perl handle removing
+    # stuff from the $self hash because some stuff (eg database handles)
+    # may need special casing
+    # under a persistent environment (ie mod_perl)
+    $self->_cleanup;
+}
+
+1;
+
+__END__
+
+=head1 NAME
+
+Bugzilla - Semi-persistent collection of various objects used by scripts
+and modules
+
+=head1 SYNOPSIS
+
+  use Bugzilla;
+
+  Bugzilla->create;
+
+  sub someModulesSub {
+    my $B = Bugzilla->instance;
+    $B->template->process(...);
+  }
+
+=head1 DESCRIPTION
+
+Several Bugzilla 'things' are used by a variety of modules and scripts. This
+includes database handles, template objects, and so on.
+
+This module is a singleton intended as a central place to store these objects.
+This approach has several advantages:
+
+=over 4
+
+=item *
+
+They're not global variables, so we don't have issues with them staying arround
+with mod_perl
+
+=item *
+
+Everything is in one central place, so its easy to access, modify, and maintain
+
+=item *
+
+Code in modules can get access to these objects without having to have them
+all passed from the caller, and the caller's caller, and....
+
+=item *
+
+We can reuse objects across requests using mod_perl where appropriate (eg
+templates), whilst destroying those which are only valid for a single request
+(such as the current user)
+
+=back
+
+Note that items accessible via this object may be loaded when the Bugzilla
+object is created, or may be demand-loaded when requested.
+
+For something to be added to this object, it should either be able to benefit
+from persistence when run under mod_perl (such as the a C<template> object),
+or should be something which is globally required by a large ammount of code
+(such as the current C<user> object).
+
+=head1 CREATION
+
+=over 4
+
+=item C<create>
+
+Creates the C<Bugzilla> object, and initialises any per-request data
+
+=item C<instance>
+
+Returns the current C<Bugzilla> instance. If one doesn't exist, then it will
+be created, but no per-request data will be set. The only use this method has
+for creating the object is from a mod_perl init script. (Its also what
+L<Class::Singleton> does, and I'm trying to keep that interface for this)
+
+=back
+
+=head1 FUNCTIONS
+
+=over 4
+
+=item C<template>
+
+The current C<Template> object, to be used for output
+
+=item C<cgi>
+
+The current C<cgi> object. Note that modules should B<not> be using this in
+general. Not all Bugzilla actions are cgi requests. Its useful as a convenience
+method for those scripts/templates which are only use via CGI, though.
+
+=back