[pve-devel] [PATCH cluster 3/3] cluster: add helper to retrieve proxies

[Maximiliano Sandoval]

This will take into account the multiple layers of fallbacks and has
some rudimentary error handling.

Signed-off-by: Maximiliano Sandoval <m.sandoval at proxmox.com>
---
 src/PVE/Cluster.pm | 58 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/src/PVE/Cluster.pm b/src/PVE/Cluster.pm
index e829687..7e7f180 100644
--- a/src/PVE/Cluster.pm
+++ b/src/PVE/Cluster.pm
@@ -25,6 +25,7 @@ use PVE::Cluster::IPCConst;
 use base 'Exporter';
 
 our @EXPORT_OK = qw(
+    get_proxy
     cfs_read_file
     cfs_write_file
     cfs_register_file
@@ -904,4 +905,61 @@ sub cfs_backup_database {
     return $dbfile;
 }
 
+=head3 get_proxy($scalar, $scalar, $scalar)
+
+Returns the proxy to be used for a given protocol and use-case.
+
+Parameters:
+
+=over
+
+=item C<$dccfg>
+
+The datacenter's configuration.
+
+=item C<$protocol>
+
+The protocol of the connection, can be one of C<http> or C<https>.
+
+=item C<$type>
+
+The use-case for the proxy. It can one of C<apt>, C<download>, or C<subscription>.
+
+=back
+
+=cut
+
+sub get_proxy {
+    my ($dccfg, $protocol, $type) = @_;
+
+    if ($protocol ne 'http' && $protocol ne 'https') {
+        die "Unsupported protocol $protocol when obtaining a proxy\n";
+    }
+
+    my $proxy;
+
+    # This could be simplified with some f-strings, but it is intentionally left
+    # out in a verbose form to accommodate for edge cases, like subscriptions
+    # which are exclusively handled with a HTTPS proxy.
+    if ($type eq 'subscription' && $protocol eq 'https') {
+        $proxy = $dccfg->{proxy}->{'https-subscription'};
+    } elsif ($type eq 'download' && $protocol eq 'http') {
+        $proxy = $dccfg->{proxy}->{'http-download'};
+    } elsif ($type eq 'download' && $protocol eq 'https') {
+        $proxy = $dccfg->{proxy}->{'https-download'};
+    } elsif ($type eq 'apt' && $protocol eq 'http') {
+        $proxy = $dccfg->{proxy}->{'http-apt'};
+    } elsif ($type eq 'apt' && $protocol eq 'https') {
+        $proxy = $dccfg->{proxy}->{'https-apt'};
+    } else {
+        die "Unsupported type $type for protocol $protocol when obtaining a proxy\n";
+    }
+
+    $proxy //= $dccfg->{proxy}->{global};
+    $proxy //= $dccfg->{http_proxy};
+    $proxy = undef if $proxy eq 'none';
+
+    return $proxy;
+}
+
 1;
-- 
2.47.3