From 0457ce3d5601de62f695d8a0759a7c0b6923701c Mon Sep 17 00:00:00 2001
From: "B. Watson" <yalhcru@gmail.com>
Date: Thu, 26 Nov 2020 14:11:40 -0500
Subject: mkslackinfo: add github URL rewriting, check the result against
 Content-Disposition

---
 mkslackinfo | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/mkslackinfo b/mkslackinfo
index 48ef089..40198dd 100755
--- a/mkslackinfo
+++ b/mkslackinfo
@@ -92,12 +92,59 @@ EOF
 	return $cmd;
 }
 
+sub check_github_disposition {
+	my $url = shift;
+	my $filename = shift;
+	my $disposition;
+
+	warn "Checking github Content-Disposition header\n";
+	open my $fh, "wget --quiet --save-headers -O- $url|";
+	while(<$fh>) {
+		s/\r//;
+		if(/^Content-Disposition:\s*attachment;\s*filename=(.*)$/i) {
+			$disposition = $1;
+			last;
+		}
+		last if /^$/;
+	}
+	close $fh;
+
+	if(not defined $disposition) {
+		die "!!! Got no Content-Disposition header from github!\n";
+	} elsif($filename eq $disposition) {
+		warn "=== URL filename matches Content-Disposition filename, good.\n";
+	} else {
+		die "!!! Content-Disposition filename mismatch:\n!!!   local: $filename\n!!!   remote: $disposition\n";
+	}
+}
+
+sub fix_github_url {
+	my $u = shift;
+	return $u unless ($u =~ m,https?://github.com/([^/]+)/([^/]+)/archive/([^/]+)(\.(?:tar.gz|zip))$,);
+	my $user = $1;
+	my $proj = $2;
+	my $aversion = $3;
+	my $pversion = $3;
+	my $ext = $4;
+
+	warn "Converting short-form github URL to long form\n";
+	$pversion =~ s/^v//; # maybe other letters?
+	my $filename = "$proj-$pversion$ext";
+	$u = "https://github.com/$user/$proj/archive/$aversion/$proj-$pversion$ext";
+	check_github_disposition($u, $filename);
+	warn "=== Rewrote github URL as: $url\n";
+	return $u;
+}
+
+### main()
 $url = shift || &usage;
 
 # Take package name from the current dir
 chomp ($package = `pwd`);
 $package =~ s,.*/,,;
 
+$url = fix_github_url($url);
+
 # Take filename from last part of URL
 ($file = $url) =~ s,.*/,,;
 
-- 
cgit v1.2.3