MT#4229 custom Internal server error page

Move error_page to notfound_page. error_page is now for internal server errors.
Introduce logging option log_crash_state, enabled by default. Crash states are
written out compressed and encoded log-file-friendly, these are useful for
debugging but take a couple dozen kilobytes of disk space each.

Build.PL

@@ -32,9 +32,12 @@ my $builder = Local::Module::Build->new(
         'Catalyst::View::JSON' => 0,
         'Catalyst::View::TT' => 0,
         'Config::General' => 0,
+        'Convert::Ascii85' => 0,
+        'Data::Dumper' => 0,
         'Data::Validate::IP' => 0,
         'DateTime' => 0,
         'DateTime::Format::ISO8601' => 0,
+        'DateTime::Format::RFC3339' => 0,
         'DBIx::Class::ResultSet::RecursiveUpdate' => '0.30',
         'Email::Valid' => 0,
         'File::ShareDir' => 0,
@@ -49,6 +52,7 @@ my $builder = Local::Module::Build->new(
         'HTML::FormHandler::Moose' => 0,
         'HTML::FormHandler::Widget::Block::Bootstrap' => 0,
         'HTTP::Status' => 0,
+        'IO::Compress::Xz' => 0,
         'IPC::System::Simple' => 0,
         'Log::Log4perl::Catalyst' => 0,
         'Module::Runtime' => 0,
@@ -65,6 +69,7 @@ my $builder = Local::Module::Build->new(
         'strict' => 0,
         'Template' => 0,
         'Text::CSV_XS' => 0,
+        'Time::HiRes' => 0,
         'URI::Encode' => 0,
         'URI::Escape' => 0,
         'UUID' => 0,
@@ -95,6 +100,9 @@ my $builder = Local::Module::Build->new(
         # for the testcover target
         'Devel::Cover' => 0,
         'sigtrap' => 0,
+        # for development
+        'Convert::Ascii85' => 0,
+        'IO::Uncompress::UnXz' => 0,
     },
     add_to_cleanup => [ 'NGCP-Panel-*' ],
 );

lib/NGCP/Panel/Controller/Root.pm

@@ -1,11 +1,15 @@
 package NGCP::Panel::Controller::Root;
 use Sipwise::Base;
-
-
 BEGIN { extends 'Catalyst::Controller' }
-
+use Carp qw(longmess);
+use Convert::Ascii85 qw();
+use Data::Dumper qw(Dumper);
+use DateTime qw();
+use DateTime::Format::RFC3339 qw();
+use IO::Compress::Xz qw(xz);
 use NGCP::Panel::Widget;
 use Scalar::Util qw(blessed);
+use Time::HiRes qw();
 
 #
 # Sets the actions in this controller to be registered with no prefix
@@ -111,7 +115,41 @@ sub default :Path {
     $c->detach( '/error_page' );
 }
 
-sub end : ActionClass('RenderView') {}
+sub render :ActionClass('RenderView') { }
+
+sub end :Private {
+    my ($self, $c) = @_;
+    $c->forward('render');
+    if (@{ $c->error }) {
+        my $incident = DateTime->from_epoch(epoch => Time::HiRes::time);
+        my $incident_id = sprintf '%X', $incident->strftime('%s%N');
+        my $incident_timestamp = DateTime::Format::RFC3339->new->format_datetime($incident);
+        my $crash_state;
+        if ($c->config->{log_crash_state}) {
+            local $Data::Dumper::Indent = 1;
+            local $Data::Dumper::Useqq = 1;
+            local $Data::Dumper::Deparse = 1;
+            local $Data::Dumper::Quotekeys = 0;
+            local $Data::Dumper::Sortkeys = 1;
+            my $buffer;
+            xz(\(join(q(), @{ $c->error }) . longmess . Dumper($c) . Dumper($c->config)), \$buffer);
+            $crash_state = Convert::Ascii85::encode($buffer);
+            $crash_state =~ s/(.{80})/$1\n/g;
+        }
+        $c->log->error(
+            "Exception id $incident_id at $incident_timestamp crash_state:" .
+            ($crash_state ? ("\n" . $crash_state) : ' disabled')
+        );
+        $c->clear_errors;
+        $c->stash(
+            exception_incident => $incident_id,
+            exception_timestamp => $incident_timestamp,
+            template => 'error_page.tt'
+        );
+        $c->response->status(500);
+        $c->detach($c->view);
+    }
+}
 
 sub _prune_row {
     my ($columns, %row) = @_;
@@ -129,8 +167,7 @@ sub error_page :Private {
     my ($self,$c) = @_;
     
     $c->log->error( 'Failed to find path ' . $c->request->path );
-    $c->stash(template => 'error_page.tt');
-    #$c->response->body( 'Page not found' );
+    $c->stash(template => 'notfound_page.tt');
     $c->response->status(404);
 }
 

ngcp_panel.conf

@@ -10,6 +10,9 @@ log4perl.appender.Default.layout=PatternLayout
 log4perl.appender.Default.layout.ConversionPattern=%d{ISO8601} [%p] [%F +%L] %m{chomp}%n
 # perhaps also add: host=%H pid=%P
 
+# each crash state is <50 KiB
+log_crash_state 1
+
 <Model::DB>
     schema_class   NGCP::Schema
 </Model::DB>

script/ngcp_panel_decode_crash

@@ -0,0 +1,21 @@
+#!/usr/bin/env perl
+use Convert::Ascii85 qw();
+use IO::Uncompress::UnXz qw(unxz $UnXzError);
+
+local $/ = undef;
+my $buf = Convert::Ascii85::decode(<>);
+my $out;
+unxz \$buf, \$out or die $UnXzError;
+print $out;
+
+__END__
+
+=encoding UTF-8
+
+=head1 NAME
+
+ngcp_panel_decode_crash - decode a crash state from the Web server error log
+
+=head1 USAGE
+
+    ngcp_panel_decode_crash < crashfile

share/templates/error_page.tt

@@ -6,11 +6,16 @@
 			
 			<h1>Oops!</h1>
 			
-			<h2>[% c.response.status %] Not found</h2>
+			<h2>[% c.response.status %] Internal server error </h2>
 			
 			<div class="error-details">
-				Sorry, an error has occured, Requested page not found!
-				
+				<p>Sorry, an exceptional error has occured:</p>
+				<ul>
+				<li>incident number: [% exception_incident %]</li>
+				<li>time of incident: [% exception_timestamp %]</li>
+				</ul>
+				<p>Details have been logged on the server. If you want to report the error,
+				describe what you were doing or attempting to do just before.</p>
 			</div> <!-- /error-details -->
 			
 			<div class="error-actions">

share/templates/notfound_page.tt

@@ -0,0 +1,37 @@
+<div class="row">
+	
+	<div class="span12">
+		
+		<div class="error-container">
+			
+			<h1>Oops!</h1>
+			
+			<h2>[% c.response.status %] Not found</h2>
+			
+			<div class="error-details">
+				Sorry, an error has occured, Requested page not found!
+				
+			</div> <!-- /error-details -->
+			
+			<div class="error-actions">
+				<a href="[% c.uri_for('/back') %]" class="btn btn-large btn-primary">
+					<i class="icon-chevron-left"></i>
+					&nbsp;
+					Back to Dashboard						
+				</a>
+				
+				<a href="mailto:[% c.config.contact.email %]" class="btn btn-large">
+					<i class="icon-envelope"></i>
+					&nbsp;
+					Contact Support						
+				</a>
+				
+			</div> <!-- /error-actions -->
+						
+		</div> <!-- /.error-container -->				
+		
+		
+	</div> <!-- /.span12 -->
+	
+</div> <!-- /.row -->		
+