p2p/discover: parametrize nodedb version, add persistency tests

3 files changed, 62 insertions, 11 deletions

diff --git a/p2p/discover/database.go b/p2p/discover/database.go
index 74c9c6af3..b7c0c0498 100644
--- a/p2p/discover/database.go
+++ b/p2p/discover/database.go
@@ -39,11 +39,11 @@ var (
 // newNodeDB creates a new node database for storing and retrieving infos about
 // known peers in the network. If no path is given, an in-memory, temporary
 // database is constructed.
-func newNodeDB(path string) (*nodeDB, error) {
+func newNodeDB(path string, version int) (*nodeDB, error) {
 	if path == "" {
 		return newMemoryNodeDB()
 	}
-	return newPersistentNodeDB(path)
+	return newPersistentNodeDB(path, version)
 }
 
 // newMemoryNodeDB creates a new in-memory node database without a persistent
@@ -58,7 +58,7 @@ func newMemoryNodeDB() (*nodeDB, error) {
 
 // newPersistentNodeDB creates/opens a leveldb backed persistent node database,
 // also flushing its contents in case of a version mismatch.
-func newPersistentNodeDB(path string) (*nodeDB, error) {
+func newPersistentNodeDB(path string, version int) (*nodeDB, error) {
 	// Try to open the cache, recovering any corruption
 	db, err := leveldb.OpenFile(path, nil)
 	if _, iscorrupted := err.(leveldb.ErrCorrupted); iscorrupted {
@@ -70,7 +70,7 @@ func newPersistentNodeDB(path string) (*nodeDB, error) {
 	// The nodes contained in the cache correspond to a certain protocol version.
 	// Flush all nodes if the version doesn't match.
 	currentVer := make([]byte, binary.MaxVarintLen64)
-	currentVer = currentVer[:binary.PutVarint(currentVer, Version)]
+	currentVer = currentVer[:binary.PutVarint(currentVer, int64(version))]
 
 	blob, err := db.Get(nodeDBVersionKey, nil)
 	switch err {
@@ -88,7 +88,7 @@ func newPersistentNodeDB(path string) (*nodeDB, error) {
 			if err = os.RemoveAll(path); err != nil {
 				return nil, err
 			}
-			return newPersistentNodeDB(path)
+			return newPersistentNodeDB(path, version)
 		}
 	}
 	return &nodeDB{lvl: db}, nil
diff --git a/p2p/discover/database_test.go b/p2p/discover/database_test.go
index b067d458d..0412a4770 100644
--- a/p2p/discover/database_test.go
+++ b/p2p/discover/database_test.go
@@ -2,7 +2,10 @@ package discover
 
 import (
 	"bytes"
+	"io/ioutil"
 	"net"
+	"os"
+	"path/filepath"
 	"testing"
 	"time"
 )
@@ -59,7 +62,8 @@ var nodeDBInt64Tests = []struct {
 }
 
 func TestNodeDBInt64(t *testing.T) {
-	db, _ := newNodeDB("")
+	db, _ := newNodeDB("", Version)
+	defer db.close()
 
 	tests := nodeDBInt64Tests
 	for i := 0; i < len(tests); i++ {
@@ -87,7 +91,9 @@ func TestNodeDBFetchStore(t *testing.T) {
 		TCPPort: 30303,
 	}
 	inst := time.Now()
-	db, _ := newNodeDB("")
+
+	db, _ := newNodeDB("", Version)
+	defer db.close()
 
 	// Check fetch/store operations on a node ping object
 	if stored := db.lastPing(node.ID); stored.Unix() != 0 {
@@ -151,7 +157,8 @@ var nodeDBSeedQueryNodes = []struct {
 }
 
 func TestNodeDBSeedQuery(t *testing.T) {
-	db, _ := newNodeDB("")
+	db, _ := newNodeDB("", Version)
+	defer db.close()
 
 	// Insert a batch of nodes for querying
 	for i, seed := range nodeDBSeedQueryNodes {
@@ -190,7 +197,8 @@ func TestNodeDBSeedQuery(t *testing.T) {
 }
 
 func TestNodeDBSeedQueryContinuation(t *testing.T) {
-	db, _ := newNodeDB("")
+	db, _ := newNodeDB("", Version)
+	defer db.close()
 
 	// Insert a batch of nodes for querying
 	for i, seed := range nodeDBSeedQueryNodes {
@@ -213,3 +221,46 @@ func TestNodeDBSeedQueryContinuation(t *testing.T) {
 		}
 	}
 }
+
+func TestNodeDBPersistency(t *testing.T) {
+	root, err := ioutil.TempDir("", "nodedb-")
+	if err != nil {
+		t.Fatalf("failed to create temporary data folder: %v", err)
+	}
+	defer os.RemoveAll(root)
+
+	var (
+		testKey = []byte("somekey")
+		testInt = int64(314)
+	)
+
+	// Create a persistent database and store some values
+	db, err := newNodeDB(filepath.Join("root", "database"), Version)
+	if err != nil {
+		t.Fatalf("failed to create persistent database: %v", err)
+	}
+	if err := db.storeInt64(testKey, testInt); err != nil {
+		t.Fatalf("failed to store value: %v.", err)
+	}
+	db.close()
+
+	// Reopen the database and check the value
+	db, err = newNodeDB(filepath.Join("root", "database"), Version)
+	if err != nil {
+		t.Fatalf("failed to open persistent database: %v", err)
+	}
+	if val := db.fetchInt64(testKey); val != testInt {
+		t.Fatalf("value mismatch: have %v, want %v", val, testInt)
+	}
+	db.close()
+
+	// Change the database version and check flush
+	db, err = newNodeDB(filepath.Join("root", "database"), Version+1)
+	if err != nil {
+		t.Fatalf("failed to open persistent database: %v", err)
+	}
+	if val := db.fetchInt64(testKey); val != 0 {
+		t.Fatalf("value mismatch: have %v, want %v", val, 0)
+	}
+	db.close()
+}
diff --git a/p2p/discover/table.go b/p2p/discover/table.go
index ecfb8d672..11bdff198 100644
--- a/p2p/discover/table.go
+++ b/p2p/discover/table.go
@@ -63,10 +63,10 @@ type bucket struct {
 
 func newTable(t transport, ourID NodeID, ourAddr *net.UDPAddr, nodeDBPath string) *Table {
 	// If no node database was given, use an in-memory one
-	db, err := newNodeDB(nodeDBPath)
+	db, err := newNodeDB(nodeDBPath, Version)
 	if err != nil {
 		glog.V(logger.Warn).Infoln("Failed to open node database:", err)
-		db, _ = newNodeDB("")
+		db, _ = newNodeDB("", Version)
 	}
 	tab := &Table{
 		net:       t,