Merge pull request #227 from libp2p/revert-224-remove-signal-bootstrap

Revert "Remove signal bootstrapping"

dht_bootstrap.go

@@ -8,6 +8,7 @@ import (
 
 	u "github.com/ipfs/go-ipfs-util"
 	goprocess "github.com/jbenet/goprocess"
+	periodicproc "github.com/jbenet/goprocess/periodic"
 	peer "github.com/libp2p/go-libp2p-peer"
 	routing "github.com/libp2p/go-libp2p-routing"
 )
@@ -89,6 +90,26 @@ func (dht *IpfsDHT) BootstrapWithConfig(cfg BootstrapConfig) (goprocess.Process,
 	return proc, nil
 }
 
+// SignalBootstrap ensures the dht routing table remains healthy as peers come and go.
+// it builds up a list of peers by requesting random peer IDs. The Bootstrap
+// process will run a number of queries each time, and run every time signal fires.
+// These parameters are configurable.
+//
+// SignalBootstrap returns a process, so the user can stop it.
+func (dht *IpfsDHT) BootstrapOnSignal(cfg BootstrapConfig, signal <-chan time.Time) (goprocess.Process, error) {
+	if cfg.Queries <= 0 {
+		return nil, fmt.Errorf("invalid number of queries: %d", cfg.Queries)
+	}
+
+	if signal == nil {
+		return nil, fmt.Errorf("invalid signal: %v", signal)
+	}
+
+	proc := periodicproc.Ticker(signal, dht.bootstrapWorker(cfg))
+
+	return proc, nil
+}
+
 func (dht *IpfsDHT) bootstrapWorker(cfg BootstrapConfig) func(worker goprocess.Process) {
 	return func(worker goprocess.Process) {
 		// it would be useful to be able to send out signals of when we bootstrap, too...

dht_test.go

@@ -679,10 +679,23 @@ func TestPeriodicBootstrap(t *testing.T) {
 		}
 	}()
 
+	signals := []chan time.Time{}
+
 	var cfg BootstrapConfig
 	cfg = DefaultBootstrapConfig
 	cfg.Queries = 5
 
+	// kick off periodic bootstrappers with instrumented signals.
+	for _, dht := range dhts {
+		s := make(chan time.Time)
+		signals = append(signals, s)
+		proc, err := dht.BootstrapOnSignal(cfg, s)
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer proc.Close()
+	}
+
 	t.Logf("dhts are not connected. %d", nDHTs)
 	for _, dht := range dhts {
 		rtlen := dht.routingTable.Size()
@@ -708,11 +721,9 @@ func TestPeriodicBootstrap(t *testing.T) {
 	}
 
 	t.Logf("bootstrapping them so they find each other. %d", nDHTs)
-	for _, dht := range dhts {
-		_, err := dht.BootstrapWithConfig(cfg)
-		if err != nil {
-			t.Fatalf("error bootstrapping a dht: %s", err)
-		}
+	now := time.Now()
+	for _, signal := range signals {
+		go func(s chan time.Time) { s <- now }(signal)
 	}
 
 	// this is async, and we dont know when it's finished with one cycle, so keep checking