generate.pl: allow setting alternate dir for downloads

This can be helpful in docker volumes or dev containers, where using the default
location under the repo root can have issues due to host/container sync.

Author: zakame

generate.pl

@@ -122,8 +122,9 @@ sub die_with_sample {
 die_with_sample unless defined $config->{releases};
 die_with_sample unless ref $config->{releases} eq "ARRAY";
 
-if (!-d "downloads") {
-  mkdir "downloads" or die "Couldn't create a downloads directory";
+my $downloads = $ENV{DOCKER_PERL_DOWNLOADS_DIR} // "downloads";
+if (!-d "$downloads") {
+  mkdir "$downloads" or die "Couldn't create a downloads directory at $downloads";
 }
 
 for my $build (@{$config->{builds}}) {
@@ -141,21 +142,21 @@ sub die_with_sample {
   my $tarball = CPAN::Perl::Releases::MetaCPAN::perl_tarballs($release->{version})->{'tar.gz'};
   my ($file)  = File::Basename::fileparse($tarball);
   my $url     = "https://cpan.metacpan.org/authors/id/$tarball";
-  if (-f "downloads/$file" && `sha256sum downloads/$file` =~ /^\Q$release->{sha256}\E\s+\Qdownloads\/$file\E/) {
+  if (-f "$downloads/$file" && `sha256sum $downloads/$file` =~ /^\Q$release->{sha256}\E\s+\Q$downloads\/$file\E/) {
     print "Skipping download of $file, already current\n";
   }
   else {
     print "Downloading $url\n";
-    getstore($url, "downloads/$file");
+    getstore($url, "$downloads/$file");
   }
   {
-    my $dir = "downloads/perl-$release->{version}";
+    my $dir = "$downloads/perl-$release->{version}";
     qx{rm -fR $dir};
     mkdir $dir or die "Couldn't create $dir";
     qx{
-      tar -C "downloads" -xf $dir.tar.gz &&\
+      tar -C "$downloads" -xf $dir.tar.gz &&\
       cd $dir &&\
-      find . -exec chmod u+w {} + &&\
+      chown -R \$(id -u):\$(id -g) . &&\
       git init &&\
       git add . &&\
       git commit -m tmp