From a97c1c9d86dfcb4c73a748d6e4635e959d2ff46c Mon Sep 17 00:00:00 2001 From: Scott Walters Date: Wed, 4 May 2011 23:16:02 -0400 Subject: [PATCH] middleware based on Plack::Middleware::StackTrace that also dumps all of the assets in a YUI tree view because that seemed like a good idea at the time. --- lib/WebGUI/Middleware/StackTrace.pm | 358 ++++++++++++++++++++++++++++ 1 file changed, 358 insertions(+) create mode 100644 lib/WebGUI/Middleware/StackTrace.pm diff --git a/lib/WebGUI/Middleware/StackTrace.pm b/lib/WebGUI/Middleware/StackTrace.pm new file mode 100644 index 000000000..bed7dc09e --- /dev/null +++ b/lib/WebGUI/Middleware/StackTrace.pm @@ -0,0 +1,358 @@ +package WebGUI::Middleware::StackTrace; + +use strict; +use warnings; +use parent qw/Plack::Middleware/; +use Devel::StackTrace; +use Devel::StackTrace::AsHTML; +use Try::Tiny; +use Plack::Util::Accessor qw( force no_print_errors ); +use Scalar::Util 'blessed'; +use Data::Dumper; +use Plack::Middleware::StackTrace; +use WebGUI::Session::Log; + +BEGIN { + + our $StackTraceClass = "Devel::StackTrace"; + if (try { require Devel::StackTrace::WithLexicals; 1 }) { + $StackTraceClass = "Devel::StackTrace::WithLexicals"; + } + + my $old_fatal = *WebGUI::Session::Log::fatal{CODE}; + no warnings 'redefine'; + + *WebGUI::Session::Log::fatal = sub { + my $self = shift; + my $message = shift; + $self->{_stacktrace} = $StackTraceClass->new; + $old_fatal->($self, $message, @_); + }; + +} + +# Optional since it needs PadWalker + +sub call { + my($self, $env) = @_; + + my $res = try { $self->app->($env) }; + + if( my $trace = $env->{'webgui.session'}->log->{_stacktrace} ) { + + undef $env->{'webgui.session'}->log->{_stacktrace}; # the stack trace modules do create circular references; this is necessary + + my $text = trace_as_string($trace); + $env->{'psgi.errors'}->print($text) unless $self->no_print_errors; + my $html = eval { trace_as_html($trace, $env->{'webgui.session'}) }; + if ( $html and ($env->{HTTP_ACCEPT} || '*/*') =~ /html/) { + $res = [500, ['Content-Type' => 'text/html; charset=utf-8'], [ utf8_safe($html) ]]; + } else { + $res = [500, ['Content-Type' => 'text/plain; charset=utf-8'], [ utf8_safe($text) ]]; + } + + } + + return $res; +} + + +sub trace_as_string { + my $trace = shift; + + my $st = ''; + my $first = 1; + foreach my $f ( $trace->frames() ) { + $st .= "\t" unless $first; + $st .= $f->as_string($first) . "\n"; + $first = 0; + } + + return $st; +} + +do { + no strict 'subs'; + no strict 'refs'; + *encode_html = *Devel::StackTrace::AsHTML::encode_html{CODE}; + *_build_context = *Devel::StackTrace::AsHTML::_build_context{CODE}; + *_build_arguments = *Devel::StackTrace::AsHTML::_build_arguments{CODE}; + *_build_lexicals = *Devel::StackTrace::AsHTML::_build_lexicals{CODE}; + # XXX what else? +}; + +sub trace_as_html { + + my $trace = shift; + my $session = shift or die; + my %opt = @_; + + # replaces: my $ret = $trace->as_html; + # ... which just did __PACKAGE__->render + # render copied and inlined here + + my $extras = sub { $session->url->extras(@_) }; + + my $msg = encode_html($trace->frame(1)->args); + my $out = qq{Error: ${msg}}; + + $opt{style} ||= \<${$opt{style}}); + } else { + $out .= qq(); + } + + $out .= < +function toggleThing(ref, type, hideMsg, showMsg) { + var css = document.getElementById(type+'-'+ref).style; + css.display = css.display == 'block' ? 'none' : 'block'; + + var hyperlink = document.getElementById('toggle-'+ref); + hyperlink.textContent = css.display == 'block' ? hideMsg : showMsg; +} + +function toggleArguments(ref) { + toggleThing(ref, 'arguments', 'Hide function arguments', 'Show function arguments'); +} + +function toggleLexicals(ref) { + toggleThing(ref, 'lexicals', 'Hide lexical variables', 'Show lexical variables'); +} + + + + + + + + + + + + + + +

Error trace

$msg
    +HEAD + +warn "came up with URL to treeview-min.js: @{[ $extras->('yui/build/treeview/treeview-min.js') ]}"; + + my $accumulated_asset_info = []; # record the stack frames from when we find an asset on the call stack + + $trace->next_frame; # ignore the head + my $i = 0; + while (my $frame = $trace->next_frame) { + + $i++; + $out .= join( + '', + '
  1. ', + $frame->subroutine ? encode_html("in " . $frame->subroutine) : '', + ' at ', + $frame->filename ? encode_html($frame->filename) : '', + ' line ', + $frame->line, + _build_asset_info($i, ($frame->args)[0], $accumulated_asset_info, $frame), # adds data to $accumulated_asset_info; this line added relative the stock Devel::StackTrace::AsHTML + q(
    ),
+            _build_context($frame) || '', 
+            q(
    ), + _build_arguments($i, [$frame->args]), + $frame->can('lexicals') ? _build_lexicals($i, $frame->lexicals) : '', + q(
    2. ), + ); + } + $out .= qq{
}; + + # dump the asset tree + + my $assets = WebGUI::Asset->getRoot($session)->getLineage(['descendants'], {returnObjects=>1}); + + my $tree = { type => 'text', label => 'root', children => [], }; + + for my $asset (@$assets) { + # create a tree structure of assets matching their lineage + # the format (arrays, hashes, fields) matches what YAHOO.treeview expects + # when we find an asset mentioned in one of the stack trace frames above, we add the saved file/line/etc info to the label + my $lineage = $asset->get('lineage'); + my @parts = $lineage =~ m/(.{6})/g; + # warn "asset: $asset lineage: $lineage parts: @parts"; + my $node = $tree; + while(@parts) { + my $part = shift @parts; + if((my $child_node) = grep $_->{lineage_chunk} eq $part, @{$node->{children}}) { + $node = $child_node; + } else { + my $label = $asset->get('title') . ': Id: ' . $asset->getId . ' Class: ' . ref($asset); + for my $message ( map $_->{message}, grep $_->{asset_id} eq $asset->getId, @$accumulated_asset_info ) { + $label .= " <----- $message"; + } + my $child_node = { + type => 'text', + label => $label, + lineage_chunk => $part, + children => [ ], + }; + push @{$node->{children}}, $child_node; + $node = $child_node; + } + } + } + + use JSON::PP; # JSON::XS creates something that's mangled + my $json_tree = JSON::PP->new->ascii->pretty->encode( [ $tree ] ); + + # warn "json_tree: $json_tree"; + # do { open my $fh, '>', 'json.debug2.js' or die $!; $fh->print($json_tree); }; + + $out .= qq{ +
  1. +
    +
+ + }; + + $out .= ""; + + return $out; +} + +sub _build_asset_info { + my($id, $asset, $accumulated_asset_info, $frame) = @_; + + return '' unless $asset and Scalar::Util::blessed($asset) and $asset->isa('WebGUI::Asset'); + + my $asset_title = $asset->get('title'); + my $asset_id = $asset->getId; + my $asset_class = ref $asset; + + my $message = "Stack frame number: $id AssetID: $asset_id Class: $asset_class Title: ``$asset_title''"; + + push @$accumulated_asset_info, { asset_id => $asset_id, message => $message, }; + + return $message; +} + +sub utf8_safe { + my $str = shift; + + # NOTE: I know messing with utf8:: in the code is WRONG, but + # because we're running someone else's code that we can't + # guarnatee which encoding an exception is encoded, there's no + # better way than doing this. The latest Devel::StackTrace::AsHTML + # (0.08 or later) encodes high-bit chars as HTML entities, so this + # path won't be executed. + if (utf8::is_utf8($str)) { + utf8::encode($str); + } + + $str; +} + +1; + +__END__ + +=head1 NAME + +Plack^HWebGUI::Middleware::StackTrace - Displays stack trace when your app dies + +=head1 SYNOPSIS + + enable "+WebGUI::Middleware::StackTrace"; + +=head1 DESCRIPTION + +This middleware is a copy and modification of L, a +middleware which catches exceptions (run-time errors) happening in your +application and displays nice stack trace screen. +This copy has been extended to display additional WebGUI specific information. + +You're recommended to use this middleware during the development and +use L in the deployment mode as a +replacement, so that all the exceptions thrown from your application +still get caught and rendered as a 500 error response, rather than +crashing the web server. + +Catching errors in streaming response is not supported. + +=head1 CONFIGURATION + +=over 4 + +=item force + + enable "+WebGUI::Middleware::StackTrace", force => 1; + +Force display the stack trace when an error occurs within your +application and the response code from your application is +500. Defaults to off. + +The use case of this option is that when your framework catches all +the exceptions in the main handler and returns all failures in your +code as a normal 500 PSGI error response. In such cases, this +middleware would never have a chance to display errors because it +can't tell if it's an application error or just random C in your +code. This option enforces the middleware to display stack trace even +if it's not the direct error thrown by the application. + +=item no_print_errors + + enable "+WebGUI::Middleware::StackTrace", no_print_errors => 1; + +Skips printing the text stacktrace to console +(C). Defaults to 0, which means the text version of the +stack trace error is printed to the errors handle, which usually is a +standard error. + +=back + +=head1 AUTHOR + +Tokuhiro Matsuno + +Tatsuhiko Miyagawa + +Scott Walters + +With code taken from: + +Tatsuhiko Miyagawa Emiyagawa@bulknews.netE + +Shawn M Moore + +HTML generation code is ripped off from L written by Tokuhiro Matsuno and Kazuho Oku. + +=head1 SEE ALSO + +L + +L L L + +=cut +