Bug 330487: Automatic Update Notification for Bugzilla - Patch by Frédéric Buclin <LpSolit@gmail.com> r=mkanat a=justdave

1 files changed, 196 insertions, 0 deletions

diff --git a/Bugzilla/Update.pm b/Bugzilla/Update.pm
new file mode 100644
index 000000000..a672bd8bb
--- /dev/null
+++ b/Bugzilla/Update.pm
@@ -0,0 +1,196 @@
+# -*- 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.
+#
+# Contributor(s): Frédéric Buclin <LpSolit@gmail.com>
+
+package Bugzilla::Update;
+
+use strict;
+
+use Bugzilla::Config qw($datadir);
+
+use constant REMOTE_FILE   => 'http://updates.bugzilla.org/bugzilla-update.xml';
+use constant LOCAL_FILE    => "/bugzilla-update.xml"; # Relative to $datadir.
+use constant TIME_INTERVAL => 604800; # Default is one week, in seconds.
+use constant TIMEOUT       => 5; # Number of seconds before timeout.
+
+# Look for new releases and notify logged in administrators about them.
+sub get_notifications {
+    return if (Bugzilla->params->{'upgrade_notification'} eq 'disabled');
+
+    # If the XML::Twig module is missing, we won't be able to parse
+    # the XML file. So there is no need to go further.
+    eval("require XML::Twig");
+    return if $@;
+
+    my $local_file = $datadir . LOCAL_FILE;
+    # Update the local XML file if this one doesn't exist or if
+    # the last modification time (stat[9]) is older than TIME_INTERVAL.
+    if (!-e $local_file || (time() - (stat($local_file))[9] > TIME_INTERVAL)) {
+        # Are we sure we didn't try to refresh this file already
+        # but we failed because we cannot modify its timestamp?
+        my $can_alter = 1;
+        if (-e $local_file) {
+            # Try to alter its last modification time.
+            $can_alter = utime(undef, undef, $local_file);
+        }
+        if ($can_alter) {
+            _synchronize_data();
+        }
+        else {
+            return {'error' => 'no_update', 'xml_file' => $local_file};
+        }
+    }
+
+    # If we cannot access the local XML file, ignore it.
+    return {'error' => 'no_access', 'xml_file' => $local_file} unless (-r $local_file);
+
+    my $twig = XML::Twig->new();
+    $twig->safe_parsefile($local_file);
+    # If the XML file is invalid, return.
+    return {'error' => 'corrupted', 'xml_file' => $local_file} if $@;
+    my $root = $twig->root;
+
+    my @releases;
+    foreach my $branch ($root->children('branch')) {
+        my $release = {
+            'branch_ver' => $branch->{'att'}->{'id'},
+            'latest_ver' => $branch->{'att'}->{'vid'},
+            'status'     => $branch->{'att'}->{'status'},
+            'url'        => $branch->{'att'}->{'url'},
+            'date'       => $branch->{'att'}->{'date'}
+        };
+        push(@releases, $release);
+    }
+
+    # On which branch is the current installation running?
+    my @current_version =
+        ($Bugzilla::Config::VERSION =~ m/^(\d+)\.(\d+)(?:(rc|\.)(\d+))?\+?$/);
+
+    my @release;
+    if (Bugzilla->params->{'upgrade_notification'} eq 'development_snapshot') {
+        @release = grep {$_->{'status'} eq 'development'} @releases;
+    }
+    elsif (Bugzilla->params->{'upgrade_notification'} eq 'latest_stable_release') {
+        @release = grep {$_->{'status'} eq 'stable'} @releases;
+    }
+    elsif (Bugzilla->params->{'upgrade_notification'} eq 'stable_branch_release') {
+        # We want the latest stable version for the current branch.
+        # If we are running a development snapshot, we won't match anything.
+        my $branch_version = $current_version[0] . '.' . $current_version[1];
+
+        # We do a string comparison instead of a numerical one, because
+        # e.g. 2.2 == 2.20, but 2.2 ne 2.20 (and 2.2 is indeed much older).
+        @release = grep {$_->{'branch_ver'} eq $branch_version} @releases;
+
+        # If the branch is now closed, we should strongly suggest
+        # to upgrade to the latest stable release available.
+        if (scalar(@release) && $release[0]->{'status'} eq 'closed') {
+            @release = grep {$_->{'status'} eq 'stable'} @releases;
+            return {'data' => $release[0], 'deprecated' => $branch_version};
+        }
+    }
+    else {
+      # Unknown parameter.
+      return {'error' => 'unknown_parameter'};
+    }
+
+    # Return if no new release is available.
+    return unless scalar(@release);
+
+    # Only notify the administrator if the latest version available
+    # is newer than the current one.
+    my @new_version =
+        ($release[0]->{'latest_ver'} =~ m/^(\d+)\.(\d+)(?:(rc|\.)(\d+))?\+?$/);
+
+    # We convert release candidates 'rc' to integers (rc ? 0 : 1) in order
+    # to compare versions easily.
+    $current_version[2] = ($current_version[2] && $current_version[2] eq 'rc') ? 0 : 1;
+    $new_version[2] = ($new_version[2] && $new_version[2] eq 'rc') ? 0 : 1;
+
+    my $is_newer = _compare_versions(\@current_version, \@new_version);
+    return ($is_newer == 1) ? {'data' => $release[0]} : undef;
+}
+
+sub _synchronize_data {
+    eval("require LWP::UserAgent");
+    return if $@;
+
+    my $local_file = $datadir . LOCAL_FILE;
+
+    my $ua = LWP::UserAgent->new();
+    $ua->timeout(TIMEOUT);
+    $ua->protocols_allowed(['http', 'https']);
+    $ua->mirror(REMOTE_FILE, $local_file);
+
+    # $ua->mirror() forces the modification time of the local XML file
+    # to match the modification time of the remote one.
+    # So we have to update it manually to reflect that a newer version
+    # of the file has effectively been requested. This will avoid
+    # any new download for the next TIME_INTERVAL.
+    utime(undef, undef, $local_file);
+}
+
+sub _compare_versions {
+    my ($old_ver, $new_ver) = @_;
+    while (scalar(@$old_ver) && scalar(@$new_ver)) {
+        my $old = shift(@$old_ver);
+        my $new = shift(@$new_ver);
+        return $new <=> $old if ($new <=> $old);
+    }
+    return scalar(@$new_ver) <=> scalar(@$old_ver);
+
+}
+
+1;
+
+__END__
+
+=head1 NAME
+
+Bugzilla::Update - Update routines for Bugzilla
+
+=head1 SYNOPSIS
+
+  use Bugzilla::Update;
+
+  # Get information about new releases
+  my $new_release = Bugzilla::Update::get_notifications();
+
+=head1 DESCRIPTION
+
+This module contains all required routines to notify you
+about new releases. It downloads an XML file from bugzilla.org
+and parses it, in order to display information based on your
+preferences. Absolutely no information about the Bugzilla version
+you are running is sent to bugzilla.org.
+
+=head1 FUNCTIONS
+
+=over
+
+=item C<get_notifications()>
+
+ Description: This function informs you about new releases, if any.
+
+ Params:      None.
+
+ Returns:     On success, a reference to a hash with data about
+              new releases, if any.
+              On failure, a reference to a hash with the reason
+              of the failure and the name of the unusable XML file.
+
+=back
+
+=cut