cache the data

Makefile.PL

@@ -9,6 +9,7 @@ requires 'Plack::Middleware::ReverseProxy';
 requires 'Time::Piece';
 requires 'Pod::Simple::XHTML';
 requires 'Log::Minimal';
+requires 'Cache::FileCache';
 
 recursive_author_tests('xt');
 

lib/PJP.pm

@@ -7,6 +7,8 @@ our $VERSION='0.01';
 use Amon2::Config::Simple;
 sub load_config { Amon2::Config::Simple->load(shift) }
 
-
+use PJP::Cache;
+my $cache = PJP::Cache->new();
+sub cache { $cache }
 
 1;

lib/PJP/Cache.pm

@@ -0,0 +1,32 @@
+use strict;
+use warnings;
+use utf8;
+
+package PJP::Cache;
+use Cache::FileCache;
+use File::stat;
+
+sub new {
+	my $class = shift;
+	bless {
+		cache => Cache::FileCache->new(),
+	}, $class;
+}
+
+sub file_cache {
+	my ($self, $prefix, $file, $cb) = @_;
+	my $cache = $self->{cache};
+	my $key = "${prefix}::${file}";
+	my $data = $cache->get($key);
+	my $stat = stat($file) or die "Cannot stat $file: $!";
+	if ($data && $data->[0] eq $stat->mtime) {
+		return $data->[1];
+	} else {
+		my $out = $cb->();
+		$cache->set($key => [$stat->mtime, $out]);
+		return $out;
+	}
+}
+
+1;
+

lib/PJP/M/Pod.pm

@@ -23,6 +23,21 @@ sub pod2html {
 	return mark_raw($out);
 }
 
+sub get_file_list {
+	my ($class, $name) = @_;
+
+    my @path = reverse sort { eval { version->parse($a->[1]) } <=> eval { version->parse($b->[1]) } } map {
+        +[ $_, map { local $_=$_; s!.*/perl/!!; s!/$name.pod!!; $_ } $_ ]
+    } glob("assets/perldoc.jp/docs/perl/*/$name.pod");
+	return @path;
+}
+
+sub get_latest_file_path {
+	my ($class, $name) = @_;
+	my ($latest) = $class->get_file_list($name);
+	return $latest;
+}
+
 {
     package PJP::Pod::Parser;
     use parent qw/Pod::Simple::XHTML/;    # for google source code prettifier

lib/PJP/M/TOC.pm

@@ -4,9 +4,23 @@ use utf8;
 
 package PJP::M::TOC;
 use Text::Xslate::Util qw/html_escape mark_raw/;
+use File::stat;
+use Log::Minimal;
 
 sub render {
-	my $class = shift;
+	my ($class, $c) = @_;
+
+	return mark_raw($c->cache->file_cache(
+		"toc", 'toc.txt', sub {
+			infof("regen toc");
+			$class->_render();
+		}
+	));
+}
+
+sub _render {
+	my ($class) = @_;
+
 	open my $fh, '<:utf8', 'toc.txt' or die "Cannot open toc.txt: $!";
 	my $out;
 	while (<$fh>) {
@@ -27,7 +41,7 @@ sub render {
 			$out .= "<br />\n";
 		}
 	}
-	return mark_raw($out);
+	$out;
 }
 
 1;

lib/PJP/Web/Dispatcher.pm

@@ -7,32 +7,30 @@ use Pod::Simple::XHTML;
 use Log::Minimal;
 use PJP::M::TOC;
 use PJP::M::Pod;
+use File::stat;
 
 get '/' => sub {
     my $c = shift;
 
-    my $toc = PJP::M::TOC->render();
+    my $toc = PJP::M::TOC->render($c);
     $c->render('index.tt', {toc => $toc});
 };
 
 get '/pod/*' => sub {
     my ($c, $p) = @_;
     my ($splat) = @{$p->{splat}};
 
-    my @path = map { $_->[0] } reverse sort { eval { version->parse($a->[1]) } <=> eval { version->parse($b->[1]) } } map {
-        +[ $_, map { local $_=$_; s!.*/perl/!!; s!/$splat.pod!!; $_ } $_ ]
-    } glob("assets/perldoc.jp/docs/perl/*/$splat.pod");
-    my ($latest) = @path;
-    my $path = $latest;
-
-    unless ($path) {
-        warnf("missing %s, %s", ddf($splat), ddf(\@path));
+    my $path_info = PJP::M::Pod->get_latest_file_path($splat);
+    unless ($path_info) {
+        warnf("missing %s, %s", $splat);
         return $c->render('please-translate.tt', {name => $splat});
     }
 
-    my ($version) = ($path =~ m{([^/]+)\/\Q$splat.pod\E\Z});
+    my ($path, $version) = @$path_info;
+    my $out = $c->cache->file_cache("pod:2", $path, sub {
+        PJP::M::Pod->pod2html($path);
+    });
 
-    my $out = PJP::M::Pod->pod2html($path);
     return $c->render('pod.tt', { body => $out, version => $version });
 };