Completed cache.Tx tests and added benchmarks

models/models.go

@@ -4,6 +4,10 @@
 
 package models
 
+import (
+	"strconv"
+)
+
 type Peer struct {
 	ID        string `json:"id"`
 	UserID    uint64 `json:"user_id"`
@@ -18,6 +22,10 @@ type Peer struct {
 	LastAnnounce int64  `json:"last_announce"`
 }
 
+func PeerMapKey(peer *Peer) string {
+	return peer.ID + ":" + strconv.FormatUint(peer.UserID, 36)
+}
+
 type Torrent struct {
 	ID       uint64 `json:"id"`
 	Infohash string `json:"infohash"`