feat: support Caddyfile

stub.go

@@ -2,6 +2,7 @@ package stub
 
 import (
 	"github.com/caddyserver/caddy/v2"
+	"github.com/caddyserver/caddy/v2/caddyconfig/caddyfile"
 )
 
 type StubDNS struct {
@@ -22,3 +23,54 @@ func (StubDNS) CaddyModule() caddy.ModuleInfo {
 		New: func() caddy.Module {return &StubDNS{}},
 	}
 }
+
+// Provision sets up the module. Implements caddy.Provisioner.
+func (p *StubDNS) Provision(ctx caddy.Context) error {
+	repl := caddy.NewReplacer()
+	p.Address = repl.ReplaceAll(p.Address, "")
+	return nil
+}
+
+// UnmarshalCaddyfile sets up the DNS provider from Caddyfile tokens. Syntax:
+//
+// stub_dns [address] {
+//     address <address>
+// }
+//
+func (s *StubDNS) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
+	for d.Next() {
+		if d.NextArg() {
+			s.Address = d.Val()
+		}
+		if d.NextArg() {
+			return d.ArgErr()
+		}
+		for nesting := d.Nesting(); d.NextBlock(nesting); {
+			switch d.Val() {
+			case "address":
+				if s.Address != "" {
+					return d.Err("Address already set")
+				}
+				if d.NextArg() {
+					s.Address = d.Val()
+				}
+				if d.NextArg() {
+					return d.ArgErr()
+				}
+			default:
+				return d.Errf("unrecognized subdirective '%s'", d.Val())
+			}
+		}
+	}
+	if s.Address == "" {
+		return d.Err("missing Address")
+	}
+	return nil
+}
+
+
+// Interface guards
+var (
+	_ caddy.Provisioner = (*StubDNS)(nil)
+	_ caddyfile.Unmarshaler = (*StubDNS)(nil)
+)