Add timestamp to config (#44)

* Add 'Created' ad an timestamp when the config is created.

* Add field 'Modified' on ClientConfig

This field updates when the user changes name or label on their config.

config.go

@@ -6,6 +6,7 @@ import (
 	"net"
 	"os"
 	"path/filepath"
+	"time"
 
 	log "github.com/sirupsen/logrus"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
@@ -32,6 +33,8 @@ type ClientConfig struct {
 	PublicKey  string
 	IP         net.IP
 	Notes      string
+	Created    string
+	Modified   string
 }
 
 // NewServerConfig creates and returns a reference to a new ServerConfig
@@ -102,6 +105,8 @@ func NewClientConfig(ip net.IP) *ClientConfig {
 		PublicKey:  key.PublicKey().String(),
 		IP:         ip,
 		Notes:      "",
+		Created:    time.Now().Format(time.RFC3339),
+		Modified:   time.Now().Format(time.RFC3339),
 	}
 
 	return &cfg

server.go

@@ -15,6 +15,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"time"
 
 	assetfs "github.com/elazarl/go-bindata-assetfs"
 	"github.com/google/nftables"
@@ -545,6 +546,8 @@ func (s *Server) EditClient(w http.ResponseWriter, r *http.Request, ps httproute
 		client.Notes = cfg.Notes
 	}
 
+	client.Modified = time.Now().Format(time.RFC3339)
+
 	s.reconfigure()
 
 	w.WriteHeader(http.StatusOK)