Improve config allowed_network_types.

- Rename values to "ipv4", "ipv6" and "any".
- Validate them when parsing.

bilibili/netprobe.go

@@ -2,17 +2,35 @@ package bilibili
 
 import (
 	"context"
+	"fmt"
 	"net"
 )
 
 type IpNetType string
 
 var (
-	IPv6Net IpNetType = "tcp6"
-	IPv4Net IpNetType = "tcp4"
-	IP64    IpNetType = "tcp"
+	IPv6Net IpNetType = "ipv6"
+	IPv4Net IpNetType = "ipv4"
+	IP64    IpNetType = "any"
 )
 
+// GetDialNetString returns the string accepted by net.Dialer::DialContext
+func (t IpNetType) GetDialNetString() string {
+	switch t {
+	case IPv4Net:
+		return "tcp4"
+	case IPv6Net:
+		return "tcp6"
+	case IP64:
+		return "tcp"
+	}
+	return ""
+}
+
+func (t IpNetType) String() string {
+	return fmt.Sprintf("%s(%s)", string(t), t.GetDialNetString())
+}
+
 type netContext = func(context.Context, string, string) (net.Conn, error)
 
 type netProbe struct {
@@ -36,6 +54,6 @@ func (p *netProbe) NextNetworkType(dialer net.Dialer) (netContext, IpNetType) {
 	network := p.list[p.i]
 	p.i++
 	return func(ctx context.Context, _, addr string) (net.Conn, error) {
-		return dialer.DialContext(ctx, string(network), addr)
+		return dialer.DialContext(ctx, network.GetDialNetString(), addr)
 	}, network
 }

main.go

@@ -9,13 +9,16 @@ import (
 	"context"
 	"fmt"
 	"github.com/akamensky/argparse"
+	"github.com/keuin/slbr/bilibili"
 	"github.com/keuin/slbr/common"
 	"github.com/keuin/slbr/logging"
 	"github.com/keuin/slbr/recording"
+	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/viper"
 	"log"
 	"os"
 	"os/signal"
+	"reflect"
 	"sync"
 	"syscall"
 )
@@ -104,7 +107,16 @@ func getTasks() (tasks []recording.TaskConfig) {
 			return
 		}
 		var gc GlobalConfig
-		err = viper.Unmarshal(&gc)
+		netType := reflect.TypeOf(bilibili.IP64)
+		err = viper.Unmarshal(&gc, func(conf *mapstructure.DecoderConfig) {
+			conf.DecodeHook = func(from reflect.Value, to reflect.Value) (interface{}, error) {
+				if to.Type() == netType &&
+					bilibili.IpNetType(from.String()).GetDialNetString() == "" {
+					return nil, fmt.Errorf("invalid IpNetType: %v", from.String())
+				}
+				return from.Interface(), nil
+			}
+		})
 		if err != nil {
 			err = fmt.Errorf("cannot parse config file \"%v\": %w", configFile, err)
 			return