convenience function for creating magnets

diff --git a/cmd/torrent-magnet/main.go b/cmd/torrent-magnet/main.go
index 68bae968700ba093adac01ba2aebfb8d2fd89700..a68cb888ca35144bef1356d299ff3b5b92c3b6b7 100644 (file)
--- a/cmd/torrent-magnet/main.go
+++ b/cmd/torrent-magnet/main.go
@@ -20,18 +20,7 @@ func main() {
                fmt.Fprintf(os.Stderr, "error reading metainfo from stdin: %s", err)
                os.Exit(1)
        }
-       ts := torrent.TorrentSpecFromMetaInfo(mi)
-       m := torrent.Magnet{
-               InfoHash: ts.InfoHash,
-               Trackers: func() (ret []string) {
-                       for _, tier := range ts.Trackers {
-                               for _, tr := range tier {
-                                       ret = append(ret, tr)
-                               }
-                       }
-                       return
-               }(),
-               DisplayName: ts.DisplayName,
-       }
-       fmt.Fprintf(os.Stdout, "%s\n", m.String())
+
+       magnet := torrent.Magnetize(mi)
+       fmt.Fprintf(os.Stdout, "%s\n", magnet.String())
 }

diff --git a/magnet.go b/magnet.go
index b326e1fc00bbea43951ae0e25f2188dd480f8cd2..e7653625bb57e35726ddc1414f3998a593456ba6 100644 (file)
--- a/magnet.go
+++ b/magnet.go
@@ -6,8 +6,11 @@ import (
        "fmt"
        "net/url"
        "strings"
+
+       "github.com/anacrolix/torrent/metainfo"
 )
 
+// Magnet
 type Magnet struct {
        InfoHash    [20]byte
        Trackers    []string
@@ -16,10 +19,10 @@ type Magnet struct {
 
 const xtPrefix = "urn:btih:"
 
-func (m *Magnet) String() (ret string) {
+func (m *Magnet) String() string {
        // net.URL likes to assume //, and encodes ':' on us, so we do most of
        // this manually.
-       ret = "magnet:?xt="
+       ret := "magnet:?xt="
        ret += xtPrefix + hex.EncodeToString(m.InfoHash[:])
        if m.DisplayName != "" {
                ret += "&dn=" + url.QueryEscape(m.DisplayName)
@@ -27,7 +30,23 @@ func (m *Magnet) String() (ret string) {
        for _, tr := range m.Trackers {
                ret += "&tr=" + url.QueryEscape(tr)
        }
-       return
+       return ret
+}
+
+// Magnetize creates a Magnet from a MetaInfo
+func Magnetize(mi *metainfo.MetaInfo) Magnet {
+       ts := TorrentSpecFromMetaInfo(mi)
+       trackers := []string{}
+       for _, tier := range ts.Trackers {
+               for _, tracker := range tier {
+                       trackers = append(trackers, tracker)
+               }
+       }
+       return Magnet{
+               InfoHash:    ts.InfoHash,
+               Trackers:    trackers,
+               DisplayName: ts.DisplayName,
+       }
 }
 
 // ParseMagnetURI parses Magnet-formatted URIs into a Magnet instance

diff --git a/magnet_test.go b/magnet_test.go
index 52a3abbf7be470d713b7ed7950ca6ca16434cdf0..4099c229d179960e5d37beaaf3ad653a5f17faf8 100644 (file)
--- a/magnet_test.go
+++ b/magnet_test.go
@@ -4,6 +4,8 @@ import (
        "encoding/hex"
        "reflect"
        "testing"
+
+       "github.com/anacrolix/torrent/metainfo"
 )
 
 var (
@@ -66,3 +68,49 @@ func TestParseMagnetURI(t *testing.T) {
        }
 
 }
+
+func Test_Magnetize(t *testing.T) {
+       mi, err := metainfo.LoadFromFile("testdata/bootstrap.dat.torrent")
+       if err != nil {
+               t.Errorf("Failed to load testdata torrent: %v", err)
+       }
+
+       magnet := Magnetize(mi)
+
+       if magnet.DisplayName != "bootstrap.dat" {
+               t.Errorf("Magnet Dispalyname is incorrect: %s", magnet.DisplayName)
+       }
+
+       ih := [20]byte{
+               54, 113, 155, 162, 206, 207, 159, 59, 215, 197,
+               171, 251, 122, 136, 233, 57, 97, 27, 83, 108,
+       }
+
+       if magnet.InfoHash != ih {
+               t.Errorf("Magnet infohash is incorrect")
+       }
+
+       trackers := []string{
+               "udp://tracker.openbittorrent.com:80",
+               "udp://tracker.openbittorrent.com:80",
+               "udp://tracker.publicbt.com:80",
+               "udp://coppersurfer.tk:6969/announce",
+               "udp://open.demonii.com:1337",
+               "http://bttracker.crunchbanglinux.org:6969/announce",
+       }
+
+       for _, expected := range trackers {
+               if !contains(magnet.Trackers, expected) {
+                       t.Errorf("Magnet does not contain expected tracker: %s", expected)
+               }
+       }
+}
+
+func contains(haystack []string, needle string) bool {
+       for _, s := range haystack {
+               if s == needle {
+                       return true
+               }
+       }
+       return false
+}