Bug#803790: fakeupstream.cgi: New Google Fonts upstream

[Gioele Barabucci <gioele@svario.it>]

Package: qa.debian.org
Severity: wishlist
Tags: patch

Hello,

the attached patch adds support for a new upstream: Google Fonts via 
GitHub. The `upstream_parameter` format is 
`google-fonts/$font_licence/$font_name`, for example 
`google-fonts/ofl/pompiere`.

Before explaining the patch I need to explain why this is needed and the 
unusual way fonts on Google Fonts are "released". To start with, fonts 
made available on Google Fonts lack proper release tarballs. Each font 
is maintained in a subdirectory that is part of a huge git repository 
hosted on GitHub (previously on Google Code).

These fonts lack also meaningful version numbers. Modifications are, 
however, almost always recorded in the `FONTLOG.txt` file that is 
present in most directories. In addition, not all the revisions of a 
certain font are available in the git history, only the latest one is 
assured to be available. For all these reasons the most reliable way to 
identify a font version is the date recorded in `FONTLOG.txt`.

The modified `fakeupstream.cgi` generates a page with a list of 
available versions for a given font. Unfortunately it is not possible to 
link these versions to release tarballs because GitHub does not generate 
tarballs for subdirectories, so the links lead to fictitious URLs.

I tested the generated page with uscan 2.15.9 and it can detects the 
current and past versions of all the fonts I tested it with.

Regards,

--
Gioele Barabucci <gioele@svario.it>

--- fakeupstream.cgi.orig	2015-11-02 13:55:28.000000000 +0000
+++ fakeupstream.cgi	2015-11-02 19:33:53.928268787 +0000
@@ -23,6 +23,8 @@
 use LWP::UserAgent;
 use JSON;
 use File::Temp qw/ tempdir /;
+use Date::Format;
+use Date::Parse;
 use Dpkg::Version;
 
 my $ca_dir = '/etc/ssl/ca-global';
@@ -735,6 +737,65 @@
 	} );
 }
 
+# http://qa.debian.org/cgi-bin/fakeupstream.cgi?upstream=google-fonts/ofl/pompiere
+elsif( $upstream_param =~ m%^google-fonts/($project_char_re+)/($project_char_re+)$% )
+{
+	my $font_licence = $1;
+	my $font_name = $2;
+
+	my $github_repo_url = "https://github.com/google/fonts/tree/master/$font_licence/$font_name";;
+	my $svn_fontlog_url = "https://github.com/google/fonts/trunk/$font_licence/$font_name/FONTLOG.txt";;
+
+	my @command = (
+		'/usr/bin/svn',
+		'cat',
+		$svn_fontlog_url
+	);
+
+	my @versions_eng;
+
+	open(my $svn_cat_fh, '-|', @command)
+		or return_error("Can't run svn cat: $!");
+	while (<$svn_cat_fh>) {
+		chomp;
+
+		# 15 July 2011 (Author) version notes
+		next unless /^([0-9]{1,2}) ([A-Za-z]+) ([0-9]{4}) /;
+
+		push @versions_eng, "$1 $2 $3"
+	}
+	close($svn_cat_fh);
+
+	return_error("no versions found for font $font_licence/$font_name")
+		if (scalar(@versions_eng) == 0);
+
+	my @versions;
+	for my $version_eng (@versions_eng) {
+		my $date = str2time($version_eng);
+		my $version = time2str("%Y%m%d", $date);
+
+		push @versions, $version;
+	}
+
+	my $result = "\n";
+	for my $version (@versions) {
+		my $release = "$font_name-$version";
+
+		$result .= $q->li( $q->a( { -href => $q->self_url . "&download=$release.zip" }, $release ) ) . "\n";
+	}
+
+	print $q->header;
+	print $q->start_html;
+	print $q->h1( "Known versions of " . $q->em( $font_name ));
+	print $q->p( "Font available at " . $q->a( { -href => "$github_repo_url" }, $github_repo_url ) );
+	print $q->start_ul;
+	print $result;
+	print $q->end_ul;
+	print $q->end_html;
+
+	exit 0;
+}
+
 my %upstream_info_per_package =
 (
 	'stopwatch' =>