reverseproxy: allow specifying ip version for dynamic `a` upstream (#5401)

Co-authored-by: Francis Lavoie <lavofr@gmail.com>

1 files changed, 24 insertions, 1 deletions

diff --git a/modules/caddyhttp/reverseproxy/caddyfile.go b/modules/caddyhttp/reverseproxy/caddyfile.go
index 1211188..cf84ba7 100644
--- a/modules/caddyhttp/reverseproxy/caddyfile.go
+++ b/modules/caddyhttp/reverseproxy/caddyfile.go
@@ -1324,6 +1324,7 @@ func (u *SRVUpstreams) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
 //	    resolvers           <resolvers...>
 //	    dial_timeout        <timeout>
 //	    dial_fallback_delay <timeout>
+//	    versions            ipv4|ipv6
 //	}
 func (u *AUpstreams) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
 	for d.Next() {
@@ -1397,8 +1398,30 @@ func (u *AUpstreams) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
 				}
 				u.FallbackDelay = caddy.Duration(dur)
 
+			case "versions":
+				args := d.RemainingArgs()
+				if len(args) == 0 {
+					return d.Errf("must specify at least one version")
+				}
+
+				if u.Versions == nil {
+					u.Versions = &ipVersions{}
+				}
+
+				trueBool := true
+				for _, arg := range args {
+					switch arg {
+					case "ipv4":
+						u.Versions.IPv4 = &trueBool
+					case "ipv6":
+						u.Versions.IPv6 = &trueBool
+					default:
+						return d.Errf("unsupported version: '%s'", arg)
+					}
+				}
+
 			default:
-				return d.Errf("unrecognized srv option '%s'", d.Val())
+				return d.Errf("unrecognized a option '%s'", d.Val())
 			}
 		}
 	}