package descriptions, unused imports, etc...

config/config.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by the BSD 2-Clause license,
 // which can be found in the LICENSE file.
 
+// Package config implements the configuration for a BitTorrent tracker
 package config
 
 import (

server/announce.go

@@ -14,32 +14,32 @@ import (
 
 func (s *Server) serveAnnounce(w http.ResponseWriter, r *http.Request) {
 	passkey, _ := path.Split(r.URL.Path)
-	user, err := validatePasskey(passkey, s.storage)
+	_, err := validatePasskey(passkey, s.storage)
 	if err != nil {
-		fail(err, w)
+		fail(err, w, r)
 		return
 	}
 
 	pq, err := parseQuery(r.URL.RawQuery)
 	if err != nil {
-		fail(errors.New("Error parsing query"), w)
+		fail(errors.New("Error parsing query"), w, r)
 		return
 	}
 
-	ip, err := pq.determineIP(r)
+	_, err = pq.determineIP(r)
 	if err != nil {
-		fail(err, w)
+		fail(err, w, r)
 		return
 	}
 
 	err = pq.validate()
 	if err != nil {
-		fail(errors.New("Malformed request"), w)
+		fail(errors.New("Malformed request"), w, r)
 		return
 	}
 
 	if !s.conf.Whitelisted(pq.params["peerId"]) {
-		fail(errors.New("Your client is not approved"), w)
+		fail(errors.New("Your client is not approved"), w, r)
 		return
 	}
 
@@ -48,7 +48,7 @@ func (s *Server) serveAnnounce(w http.ResponseWriter, r *http.Request) {
 		log.Panicf("server: %s", err)
 	}
 	if !exists {
-		fail(errors.New("This torrent does not exist"), w)
+		fail(errors.New("This torrent does not exist"), w, r)
 		return
 	}
 
@@ -66,6 +66,7 @@ func (s *Server) serveAnnounce(w http.ResponseWriter, r *http.Request) {
 				left,
 			),
 			w,
+			r,
 		)
 		return
 	}

server/query.go

@@ -97,27 +97,27 @@ func parseQuery(query string) (*parsedQuery, error) {
 }
 
 func (pq *parsedQuery) validate() error {
-	infohash, ok := pq.params["info_hash"]
+	infohash, _ := pq.params["info_hash"]
 	if infohash == "" {
 		return errors.New("infohash does not exist")
 	}
-	peerId, ok := pq.params["peer_id"]
+	peerId, _ := pq.params["peer_id"]
 	if peerId == "" {
 		return errors.New("peerId does not exist")
 	}
-	port, ok := pq.getUint64("port")
+	_, ok := pq.getUint64("port")
 	if ok == false {
 		return errors.New("port does not exist")
 	}
-	uploaded, ok := pq.getUint64("uploaded")
+	_, ok = pq.getUint64("uploaded")
 	if ok == false {
 		return errors.New("uploaded does not exist")
 	}
-	downloaded, ok := pq.getUint64("downloaded")
+	_, ok = pq.getUint64("downloaded")
 	if ok == false {
 		return errors.New("downloaded does not exist")
 	}
-	left, ok := pq.getUint64("left")
+	_, ok = pq.getUint64("left")
 	if ok == false {
 		return errors.New("left does not exist")
 	}

server/scrape.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"net/http"
 	"path"
 	"strconv"
@@ -20,13 +21,13 @@ func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
 	passkey, _ := path.Split(r.URL.Path)
 	_, err := validatePasskey(passkey, s.storage)
 	if err != nil {
-		fail(err, w)
+		fail(err, w, r)
 		return
 	}
 
 	pq, err := parseQuery(r.URL.RawQuery)
 	if err != nil {
-		fail(errors.New("Error parsing query"), w)
+		fail(errors.New("Error parsing query"), w, r)
 		return
 	}
 
@@ -36,7 +37,7 @@ func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
 		for _, infohash := range pq.infohashes {
 			torrent, exists, err := s.storage.FindTorrent(infohash)
 			if err != nil {
-				panic("server: failed to find torrent")
+				log.Panicf("server: %s", err)
 			}
 			if exists {
 				bencode(w, infohash)
@@ -46,7 +47,7 @@ func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
 	} else if infohash, exists := pq.params["info_hash"]; exists {
 		torrent, exists, err := s.storage.FindTorrent(infohash)
 		if err != nil {
-			panic("server: failed to find torrent")
+			log.Panicf("server: %s", err)
 		}
 		if exists {
 			bencode(w, infohash)
@@ -54,7 +55,11 @@ func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 	io.WriteString(w, "e")
-	finalizeResponse(w, r)
+
+	r.Close = true
+	w.Header().Add("Content-Type", "text/plain")
+	w.Header().Add("Connection", "close")
+	w.(http.Flusher).Flush()
 }
 
 func writeScrapeInfo(w io.Writer, torrent *storage.Torrent) {
@@ -69,6 +74,7 @@ func writeScrapeInfo(w io.Writer, torrent *storage.Torrent) {
 }
 
 func bencode(w io.Writer, data interface{}) {
+	// A massive switch is faster than reflection
 	switch v := data.(type) {
 	case string:
 		str := fmt.Sprintf("%s:%s", strconv.Itoa(len(v)), v)

server/server.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by the BSD 2-Clause license,
 // which can be found in the LICENSE file.
 
+// Package server implements a BitTorrent tracker
 package server
 
 import (
@@ -90,7 +91,6 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	s.waitgroup.Add(1)
 	defer s.waitgroup.Done()
 	defer atomic.AddInt64(&s.deltaRequests, 1)
-	defer finalizeResponse(w, r)
 
 	if r.URL.Path == "/stats" {
 		s.serveStats(w, r)
@@ -106,19 +106,12 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		s.serveScrape(w, r)
 		return
 	default:
-		fail(errors.New("Unknown action"), w)
+		fail(errors.New("Unknown action"), w, r)
 		return
 	}
 }
 
-func finalizeResponse(w http.ResponseWriter, r *http.Request) {
+func fail(err error, w http.ResponseWriter, r *http.Request) {
-	r.Close = true
-	w.Header().Add("Content-Type", "text/plain")
-	w.Header().Add("Connection", "close")
-	w.(http.Flusher).Flush()
-}
-
-func fail(err error, w http.ResponseWriter) {
 	errmsg := err.Error()
 	message := fmt.Sprintf(
 		"%s%s%s%s%s",
@@ -128,7 +121,12 @@ func fail(err error, w http.ResponseWriter) {
 		errmsg,
 		"e",
 	)
-	io.WriteString(w, message)
+	length, _ := io.WriteString(w, message)
+	r.Close = true
+	w.Header().Add("Content-Type", "text/plain")
+	w.Header().Add("Content-Length", string(length))
+	w.Header().Add("Connection", "close")
+	w.(http.Flusher).Flush()
 }
 
 func validatePasskey(dir string, s storage.Storage) (*storage.User, error) {

server/stats.go

@@ -23,7 +23,12 @@ func (s *Server) serveStats(w http.ResponseWriter, r *http.Request) {
 		config.Duration{time.Now().Sub(s.startTime)},
 		s.rpm,
 	})
-	w.Write(stats)
+
+	length, _ := w.Write(stats)
+	w.Header().Set("Content-Type", "application/json")
+	w.Header().Set("Content-Length", string(length))
+	w.Header().Set("Connection", "close")
+	w.(http.Flusher).Flush()
 }
 
 func (s *Server) updateRPM() {

storage/storage.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by the BSD 2-Clause license,
 // which can be found in the LICENSE file.
 
+// Package storage provides a generic interface for manipulating a
+// BitTorrent tracker's data store.
 package storage
 
 import (