make infohash and peerID byte arrays (#169)

server/http/query/query.go

@@ -20,6 +20,10 @@ import (
 // it.
 var ErrKeyNotFound = errors.New("query: value for the provided key does not exist")
 
+// ErrInvalidInfohash is returned when parsing a query encounters an infohash
+// with invalid length.
+var ErrInvalidInfohash = errors.New("query: invalid infohash")
+
 // Query represents a parsed URL.Query.
 type Query struct {
 	query      string
@@ -71,7 +75,10 @@ func New(query string) (*Query, error) {
 			}
 
 			if keyStr == "info_hash" {
-				q.infoHashes = append(q.infoHashes, chihaya.InfoHash(valStr))
+				if len(valStr) != 20 {
+					return nil, ErrInvalidInfohash
+				}
+				q.infoHashes = append(q.infoHashes, chihaya.InfoHashFromString(valStr))
 			} else {
 				q.params[strings.ToLower(keyStr)] = valStr
 			}

server/http/request.go

@@ -49,7 +49,10 @@ func announceRequest(r *http.Request, cfg *httpConfig) (*chihaya.AnnounceRequest
 	if err != nil {
 		return nil, tracker.ClientError("failed to parse parameter: peer_id")
 	}
-	request.PeerID = chihaya.PeerID(peerID)
+	if len(peerID) != 20 {
+		return nil, tracker.ClientError("failed to provide valid peer_id")
+	}
+	request.PeerID = chihaya.PeerIDFromString(peerID)
 
 	request.Left, err = q.Uint64("left")
 	if err != nil {

server/http/writer.go

@@ -71,7 +71,7 @@ func writeAnnounceResponse(w http.ResponseWriter, resp *chihaya.AnnounceResponse
 func writeScrapeResponse(w http.ResponseWriter, resp *chihaya.ScrapeResponse) error {
 	filesDict := bencode.NewDict()
 	for infohash, scrape := range resp.Files {
-		filesDict[string(infohash)] = bencode.Dict{
+		filesDict[string(infohash[:])] = bencode.Dict{
 			"complete":   scrape.Complete,
 			"incomplete": scrape.Incomplete,
 		}
@@ -91,7 +91,7 @@ func compact(peer chihaya.Peer) (buf []byte) {
 
 func dict(peer chihaya.Peer) bencode.Dict {
 	return bencode.Dict{
-		"peer id": string(peer.ID),
+		"peer id": string(peer.ID[:]),
 		"ip":      peer.IP.String(),
 		"port":    peer.Port,
 	}