swarm/network: address PR comments on TestInitialPeersMsg

* eliminate *testing.T argument from bzz/hive protocoltesters
 * add sorting (only runs in test code) on peersMsg payload
 * add random (0 to MaxPeersPerPO) peers for each po
 * add extra peers closer to pivot than control

swarm/network/discovery.go

@@ -26,6 +26,8 @@ import (
 
 // discovery bzz extension for requesting and relaying node address records
 
+var sortPeers = noSortPeers
+
 // Peer wraps BzzPeer and embeds Kademlia overlay connectivity driver
 type Peer struct {
 	*BzzPeer
@@ -181,7 +183,7 @@ func (d *Peer) handleSubPeersMsg(msg *subPeersMsg) error {
 		})
 		// if useful  peers are found, send them over
 		if len(peers) > 0 {
-			go d.Send(context.TODO(), &peersMsg{Peers: peers})
+			go d.Send(context.TODO(), &peersMsg{Peers: sortPeers(peers)})
 		}
 	}
 	d.sentPeers = true
@@ -212,3 +214,7 @@ func (d *Peer) setDepth(depth uint8) {
 	defer d.mtx.Unlock()
 	d.depth = depth
 }
+
+func noSortPeers(peers []*BzzAddr) []*BzzAddr {
+	return peers
+}

swarm/network/discovery_test.go

@@ -18,9 +18,12 @@ package network
 
 import (
 	"crypto/ecdsa"
-	"crypto/rand"
+	crand "crypto/rand"
+	"encoding/binary"
 	"fmt"
+	"math/rand"
 	"net"
+	"sort"
 	"testing"
 	"time"
 
@@ -39,7 +42,7 @@ import (
  */
 func TestSubPeersMsg(t *testing.T) {
 	params := NewHiveParams()
-	s, pp, err := newHiveTester(t, params, 1, nil)
+	s, pp, err := newHiveTester(params, 1, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -72,6 +75,7 @@ func TestSubPeersMsg(t *testing.T) {
 const (
 	maxPO         = 8 // PO of pivot and control; chosen to test enough cases but not run too long
 	maxPeerPO     = 6 // pivot has no peers closer than this to the control peer
+	maxPeersPerPO = 3
 )
 
 // TestInitialPeersMsg tests if peersMsg response to incoming subPeersMsg is correct
@@ -93,6 +97,11 @@ func testInitialPeersMsg(t *testing.T, peerPO, peerDepth int) {
 	if err != nil {
 		t.Fatal(err)
 	}
+
+	defer func(orig func([]*BzzAddr) []*BzzAddr) {
+		sortPeers = orig
+	}(sortPeers)
+	sortPeers = testSortPeers
 	pivotAddr := pot.NewAddressFromBytes(PrivateKeyToBzzKey(prvkey))
 	// generate control peers address at peerPO wrt pivot
 	peerAddr := pot.RandomAddressAt(pivotAddr, peerPO)
@@ -102,10 +111,17 @@ func testInitialPeersMsg(t *testing.T, peerPO, peerDepth int) {
 
 	// expected addrs in peersMsg response
 	var expBzzAddrs []*BzzAddr
-	connect := func(a pot.Address, po int) *BzzAddr {
-		peer := newDiscPeer(pot.RandomAddressAt(a, po))
+	connect := func(a pot.Address, po int) (addrs []*BzzAddr) {
+		n := rand.Intn(maxPeersPerPO)
+		for i := 0; i < n; i++ {
+			peer, err := newDiscPeer(pot.RandomAddressAt(a, po))
+			if err != nil {
+				t.Fatal(err)
+			}
 			hive.On(peer)
-		return peer.BzzAddr
+			addrs = append(addrs, peer.BzzAddr)
+		}
+		return addrs
 	}
 	register := func(a pot.Address, po int) {
 		addr := pot.RandomAddressAt(a, po)
@@ -115,18 +131,26 @@ func testInitialPeersMsg(t *testing.T, peerPO, peerDepth int) {
 	// generate connected and just registered peers
 	for po := maxPeerPO; po >= 0; po-- {
 		// create a fake connected peer at po from peerAddr
-		on := connect(peerAddr, po)
+		ons := connect(peerAddr, po)
 		// create a fake registered address at po from peerAddr
 		register(peerAddr, po)
 		// we collect expected peer addresses only up till peerPO
 		if po < peerDepth {
 			continue
 		}
-		expBzzAddrs = append(expBzzAddrs, on)
+		expBzzAddrs = append(expBzzAddrs, ons...)
+	}
+
+	// add extra connections closer to pivot than control
+	for po := peerPO + 1; po < maxPO; po++ {
+		ons := connect(pivotAddr, po)
+		if peerDepth <= peerPO {
+			expBzzAddrs = append(expBzzAddrs, ons...)
+		}
 	}
 
 	// create a special bzzBaseTester in which we can associate `enode.ID` to the `bzzAddr` we created above
-	s, _, err := newBzzBaseTesterWithAddrs(t, prvkey, [][]byte{peerAddr[:]}, DiscoverySpec, hive.Run)
+	s, _, err := newBzzBaseTesterWithAddrs(prvkey, [][]byte{peerAddr[:]}, DiscoverySpec, hive.Run)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -175,7 +199,7 @@ func testInitialPeersMsg(t *testing.T, peerPO, peerDepth int) {
 			Expects: []p2ptest.Expect{
 				{
 					Code:    0,
-					Msg:     &peersMsg{Peers: expBzzAddrs},
+					Msg:     &peersMsg{Peers: testSortPeers(expBzzAddrs)},
 					Peer:    peerID,
 					Timeout: 100 * time.Millisecond,
 				},
@@ -199,13 +223,23 @@ func testInitialPeersMsg(t *testing.T, peerPO, peerDepth int) {
 	}
 }
 
+func testSortPeers(peers []*BzzAddr) []*BzzAddr {
+	comp := func(i, j int) bool {
+		vi := binary.BigEndian.Uint64(peers[i].OAddr)
+		vj := binary.BigEndian.Uint64(peers[j].OAddr)
+		return vi < vj
+	}
+	sort.Slice(peers, comp)
+	return peers
+}
+
 // as we are not creating a real node via the protocol,
 // we need to create the discovery peer objects for the additional kademlia
 // nodes manually
-func newDiscPeer(addr pot.Address) *Peer {
-	pKey, err := ecdsa.GenerateKey(crypto.S256(), rand.Reader)
+func newDiscPeer(addr pot.Address) (*Peer, error) {
+	pKey, err := ecdsa.GenerateKey(crypto.S256(), crand.Reader)
 	if err != nil {
-		panic(err.Error())
+		return nil, err
 	}
 	pubKey := pKey.PublicKey
 	nod := enode.NewV4(&pubKey, net.IPv4(127, 0, 0, 1), 0, 0)
@@ -215,7 +249,7 @@ func newDiscPeer(addr pot.Address) *Peer {
 	return NewPeer(&BzzPeer{
 		Peer:    protocols.NewPeer(p2pPeer, &dummyMsgRW{}, DiscoverySpec),
 		BzzAddr: bzzAddr,
-	}, nil)
+	}, nil), nil
 }
 
 type dummyMsgRW struct{}

swarm/network/hive_test.go

@@ -28,7 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/swarm/state"
 )
 
-func newHiveTester(t *testing.T, params *HiveParams, n int, store state.Store) (*bzzTester, *Hive, error) {
+func newHiveTester(params *HiveParams, n int, store state.Store) (*bzzTester, *Hive, error) {
 	// setup
 	prvkey, err := crypto.GenerateKey()
 	if err != nil {
@@ -38,7 +38,7 @@ func newHiveTester(t *testing.T, params *HiveParams, n int, store state.Store) (
 	to := NewKademlia(addr, NewKadParams())
 	pp := NewHive(params, to, store) // hive
 
-	bt, err := newBzzBaseTester(t, n, prvkey, DiscoverySpec, pp.Run)
+	bt, err := newBzzBaseTester(n, prvkey, DiscoverySpec, pp.Run)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -49,7 +49,7 @@ func newHiveTester(t *testing.T, params *HiveParams, n int, store state.Store) (
 // and that the peer connection exists afterwards
 func TestRegisterAndConnect(t *testing.T) {
 	params := NewHiveParams()
-	s, pp, err := newHiveTester(t, params, 1, nil)
+	s, pp, err := newHiveTester(params, 1, nil)
 	if err != nil {
 		t.Fatal(err)
 	}

swarm/network/protocol_test.go

@@ -73,17 +73,17 @@ func HandshakeMsgExchange(lhs, rhs *HandshakeMsg, id enode.ID) []p2ptest.Exchang
 	}
 }
 
-func newBzzBaseTester(t *testing.T, n int, prvkey *ecdsa.PrivateKey, spec *protocols.Spec, run func(*BzzPeer) error) (*bzzTester, error) {
+func newBzzBaseTester(n int, prvkey *ecdsa.PrivateKey, spec *protocols.Spec, run func(*BzzPeer) error) (*bzzTester, error) {
 	var addrs [][]byte
 	for i := 0; i < n; i++ {
 		addr := pot.RandomAddress()
 		addrs = append(addrs, addr[:])
 	}
-	pt, _, err := newBzzBaseTesterWithAddrs(t, prvkey, addrs, spec, run)
+	pt, _, err := newBzzBaseTesterWithAddrs(prvkey, addrs, spec, run)
 	return pt, err
 }
 
-func newBzzBaseTesterWithAddrs(t *testing.T, prvkey *ecdsa.PrivateKey, addrs [][]byte, spec *protocols.Spec, run func(*BzzPeer) error) (*bzzTester, [][]byte, error) {
+func newBzzBaseTesterWithAddrs(prvkey *ecdsa.PrivateKey, addrs [][]byte, spec *protocols.Spec, run func(*BzzPeer) error) (*bzzTester, [][]byte, error) {
 	n := len(addrs)
 	cs := make(map[enode.ID]chan bool)