package discover
import (
"crypto/ecdsa"
"errors"
"fmt"
"math/rand"
"net"
"reflect"
"testing"
"testing/quick"
"time"
"github.com/ethereum/go-ethereum/crypto"
)
func TestTable_bumpOrAddPingReplace(t *testing.T) {
pingC := make(pingC)
tab := newTable(pingC, NodeID{}, &net.UDPAddr{})
last := fillBucket(tab, 200)
// this bumpOrAdd should not replace the last node
// because the node replies to ping.
new := tab.bumpOrAdd(randomID(tab.self.ID, 200), &net.UDPAddr{})
pinged := <-pingC
if pinged != last.ID {
t.Fatalf("pinged wrong node: %v\nwant %v", pinged, last.ID)
}
tab.mutex.Lock()
defer tab.mutex.Unlock()
if l := len(tab.buckets[200].entries); l != bucketSize {
t.Errorf("wrong bucket size after bumpOrAdd: got %d, want %d", bucketSize, l)
}
if !contains(tab.buckets[200].entries, last.ID) {
t.Error("last entry was removed")
}
if contains(tab.buckets[200].entries, new.ID) {
t.Error("new entry was added")
}
}
func TestTable_bumpOrAddPingTimeout(t *testing.T) {
tab := newTable(pingC(nil), NodeID{}, &net.UDPAddr{})
last := fillBucket(tab, 200)
// this bumpOrAdd should replace the last node
// because the node does not reply to ping.
new := tab.bumpOrAdd(randomID(tab.self.ID, 200), &net.UDPAddr{})
// wait for async bucket update. damn. this needs to go away.
time.Sleep(2 * time.Millisecond)
tab.mutex.Lock()
defer tab.mutex.Unlock()
if l := len(tab.buckets[200].entries); l != bucketSize {
t.Errorf("wrong bucket size after bumpOrAdd: got %d, want %d", bucketSize, l)
}
if contains(tab.buckets[200].entries, last.ID) {
t.Error("last entry was not removed")
}
if !contains(tab.buckets[200].entries, new.ID) {
t.Error("new entry was not added")
}
}
func fillBucket(tab *Table, ld int) (last *Node) {
b := tab.buckets[ld]
for len(b.entries) < bucketSize {
b.entries = append(b.entries, &Node{ID: randomID(tab.self.ID, ld)})
}
return b.entries[bucketSize-1]
}
type pingC chan NodeID
func (t pingC) findnode(n *Node, target NodeID) ([]*Node, error) {
panic("findnode called on pingRecorder")
}
func (t pingC) close() {
panic("close called on pingRecorder")
}
func (t pingC) ping(n *Node) error {
if t == nil {
return errTimeout
}
t <- n.ID
return nil
}
func TestTable_bump(t *testing.T) {
tab := newTable(nil, NodeID{}, &net.UDPAddr{})
// add an old entry and two recent ones
oldactive := time.Now().Add(-2 * time.Minute)
old := &Node{ID: randomID(tab.self.ID, 200), active: oldactive}
others := []*Node{
&Node{ID: randomID(tab.self.ID, 200), active: time.Now()},
&Node{ID: randomID(tab.self.ID, 200), active: time.Now()},
}
tab.add(append(others, old))
if tab.buckets[200].entries[0] == old {
t.Fatal("old entry is at front of bucket")
}
// bumping the old entry should move it to the front
tab.bump(old.ID)
if old.active == oldactive {
t.Error("activity timestamp not updated")
}
if tab.buckets[200].entries[0] != old {
t.Errorf("bumped entry did not move to the front of bucket")
}
}
func TestTable_closest(t *testing.T) {
t.Parallel()
test := func(test *closeTest) bool {
// for any node table, Target and N
tab := newTable(nil, test.Self, &net.UDPAddr{})
tab.add(test.All)
// check that doClosest(Target, N) returns nodes
result := tab.closest(test.Target, test.N).entries
if hasDuplicates(result) {
t.Errorf("result contains duplicates")
return false
}
if !sortedByDistanceTo(test.Target, result) {
t.Errorf("result is not sorted by distance to target")
return false
}
// check that the number of results is min(N, tablen)
wantN := test.N
if tlen := tab.len(); tlen < test.N {
wantN = tlen
}
if len(result) != wantN {
t.Errorf("wrong number of nodes: got %d, want %d", len(result), wantN)
return false
} else if len(result) == 0 {
return true // no need to check distance
}
// check that the result nodes have minimum distance to target.
for _, b := range tab.buckets {
for _, n := range b.entries {
if contains(result, n.ID) {
continue // don't run the check below for nodes in result
}
farthestResult := result[len(result)-1].ID
if distcmp(test.Target, n.ID, farthestResult) < 0 {
t.Errorf("table contains node that is closer to target but it's not in result")
t.Logf(" Target: %v", test.Target)
t.Logf(" Farthest Result: %v", farthestResult)
t.Logf(" ID: %v", n.ID)
return false
}
}
}
return true
}
if err := quick.Check(test, quickcfg); err != nil {
t.Error(err)
}
}
type closeTest struct {
Self NodeID
Target NodeID
All []*Node
N int
}
func (*closeTest) Generate(rand *rand.Rand, size int) reflect.Value {
t := &closeTest{
Self: gen(NodeID{}, rand).(NodeID),
Target: gen(NodeID{}, rand).(NodeID),
N: rand.Intn(bucketSize),
}
for _, id := range gen([]NodeID{}, rand).([]NodeID) {
t.All = append(t.All, &Node{ID: id})
}
return reflect.ValueOf(t)
}
func TestTable_Lookup(t *testing.T) {
self := gen(NodeID{}, quickrand).(NodeID)
target := randomID(self, 200)
transport := findnodeOracle{t, target}
tab := newTable(transport, self, &net.UDPAddr{})
// lookup on empty table returns no nodes
if results := tab.Lookup(target); len(results) > 0 {
t.Fatalf("lookup on empty table returned %d results: %#v", len(results), results)
}
// seed table with initial node (otherwise lookup will terminate immediately)
tab.bumpOrAdd(randomID(target, 200), &net.UDPAddr{Port: 200})
results := tab.Lookup(target)
t.Logf("results:")
for _, e := range results {
t.Logf(" ld=%d, %v", logdist(target, e.ID), e.ID)
}
if len(results) != bucketSize {
t.Errorf("wrong number of results: got %d, want %d", len(results), bucketSize)
}
if hasDuplicates(results) {
t.Errorf("result set contains duplicate entries")
}
if !sortedByDistanceTo(target, results) {
t.Errorf("result set not sorted by distance to target")
}
if !contains(results, target) {
t.Errorf("result set does not contain target")
}
}
// findnode on this transport always returns at least one node
// that is one bucket closer to the target.
type findnodeOracle struct {
t *testing.T
target NodeID
}
func (t findnodeOracle) findnode(n *Node, target NodeID) ([]*Node, error) {
t.t.Logf("findnode query at dist %d", n.DiscPort)
// current log distance is encoded in port number
var result []*Node
switch n.DiscPort {
case 0:
panic("query to node at distance 0")
default:
// TODO: add more randomness to distances
next := n.DiscPort - 1
for i := 0; i < bucketSize; i++ {
result = append(result, &Node{ID: randomID(t.target, next), DiscPort: next})
}
}
return result, nil
}
func (t findnodeOracle) close() {}
func (t findnodeOracle) ping(n *Node) error {
return errors.New("ping is not supported by this transport")
}
func hasDuplicates(slice []*Node) bool {
seen := make(map[NodeID]bool)
for _, e := range slice {
if seen[e.ID] {
return true
}
seen[e.ID] = true
}
return false
}
func sortedByDistanceTo(distbase NodeID, slice []*Node) bool {
var last NodeID
for i, e := range slice {
if i > 0 && distcmp(distbase, e.ID, last) < 0 {
return false
}
last = e.ID
}
return true
}
func contains(ns []*Node, id NodeID) bool {
for _, n := range ns {
if n.ID == id {
return true
}
}
return false
}
// gen wraps quick.Value so it's easier to use.
// it generates a random value of the given value's type.
func gen(typ interface{}, rand *rand.Rand) interface{} {
v, ok := quick.Value(reflect.TypeOf(typ), rand)
if !ok {
panic(fmt.Sprintf("couldn't generate random value of type %T", typ))
}
return v.Interface()
}
func newkey() *ecdsa.PrivateKey {
key, err := crypto.GenerateKey()
if err != nil {
panic("couldn't generate key: " + err.Error())
}
return key
}
