From a93b44b226284159bfefc744040e15e672598674 Mon Sep 17 00:00:00 2001
From: Jeromy <jeromyj@gmail.com>
Date: Sat, 15 Jul 2017 20:18:17 -0700
Subject: [PATCH 1/2] Only open a message sender when we have messages to send

License: MIT
Signed-off-by: Jeromy <jeromyj@gmail.com>
---
 exchange/bitswap/wantmanager.go | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/exchange/bitswap/wantmanager.go b/exchange/bitswap/wantmanager.go
index 780282a740f..4ae12f4998a 100644
--- a/exchange/bitswap/wantmanager.go
+++ b/exchange/bitswap/wantmanager.go
@@ -187,15 +187,6 @@ func (mq *msgQueue) runQueue(ctx context.Context) {
 }
 
 func (mq *msgQueue) doWork(ctx context.Context) {
-	if mq.sender == nil {
-		err := mq.openSender(ctx)
-		if err != nil {
-			log.Infof("cant open message sender to peer %s: %s", mq.p, err)
-			// TODO: cant connect, what now?
-			return
-		}
-	}
-
 	// grab outgoing message
 	mq.outlk.Lock()
 	wlm := mq.out
@@ -206,6 +197,16 @@ func (mq *msgQueue) doWork(ctx context.Context) {
 	mq.out = nil
 	mq.outlk.Unlock()
 
+	// NB: only open a stream if we actually have data to send
+	if mq.sender == nil {
+		err := mq.openSender(ctx)
+		if err != nil {
+			log.Infof("cant open message sender to peer %s: %s", mq.p, err)
+			// TODO: cant connect, what now?
+			return
+		}
+	}
+
 	// send wantlist updates
 	for { // try to send this message until we fail.
 		err := mq.sender.SendMsg(ctx, wlm)

From 39e9328e47dae00ad446a84686472ded9a1987c1 Mon Sep 17 00:00:00 2001
From: Jeromy <jeromyj@gmail.com>
Date: Sat, 15 Jul 2017 22:18:02 -0700
Subject: [PATCH 2/2] ensure testnet peers get evenly connected mesh

License: MIT
Signed-off-by: Jeromy <jeromyj@gmail.com>
---
 exchange/bitswap/testnet/peernet.go |  4 ++--
 exchange/bitswap/testnet/virtual.go | 21 +++++++++++++++++++++
 exchange/bitswap/testutils.go       |  2 +-
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/exchange/bitswap/testnet/peernet.go b/exchange/bitswap/testnet/peernet.go
index ef152172e61..93429ef4edd 100644
--- a/exchange/bitswap/testnet/peernet.go
+++ b/exchange/bitswap/testnet/peernet.go
@@ -1,7 +1,7 @@
 package bitswap
 
 import (
-	context "context"
+	"context"
 	bsnet "github.com/ipfs/go-ipfs/exchange/bitswap/network"
 	mockrouting "github.com/ipfs/go-ipfs/routing/mock"
 	testutil "github.com/ipfs/go-ipfs/thirdparty/testutil"
@@ -37,4 +37,4 @@ func (pn *peernet) HasPeer(p peer.ID) bool {
 	return false
 }
 
-var _ Network = &peernet{}
+var _ Network = (*peernet)(nil)
diff --git a/exchange/bitswap/testnet/virtual.go b/exchange/bitswap/testnet/virtual.go
index c41edb554b4..133ea395da7 100644
--- a/exchange/bitswap/testnet/virtual.go
+++ b/exchange/bitswap/testnet/virtual.go
@@ -9,16 +9,21 @@ import (
 	mockrouting "github.com/ipfs/go-ipfs/routing/mock"
 	delay "github.com/ipfs/go-ipfs/thirdparty/delay"
 	testutil "github.com/ipfs/go-ipfs/thirdparty/testutil"
+
 	routing "gx/ipfs/QmPjTrrSfE6TzLv6ya6VWhGcCgPrUAdcgrDcQyRDX2VyW1/go-libp2p-routing"
+	logging "gx/ipfs/QmSpJByNKFX1sCsHBEp3R73FL4NF6FnQTEGyNAXHm2GS52/go-log"
 	cid "gx/ipfs/QmTprEaAA2A9bst5XH7exuyi5KzNMK3SEDNN8rBDnKWcUS/go-cid"
 	peer "gx/ipfs/QmXYjuNuxVzXKJCfWasQk1RqkhVLDM9jtUKhqc2WPQmFSB/go-libp2p-peer"
 )
 
+var log = logging.Logger("bstestnet")
+
 func VirtualNetwork(rs mockrouting.Server, d delay.D) Network {
 	return &network{
 		clients:       make(map[peer.ID]bsnet.Receiver),
 		delay:         d,
 		routingserver: rs,
+		conns:         make(map[string]struct{}),
 	}
 }
 
@@ -26,6 +31,7 @@ type network struct {
 	clients       map[peer.ID]bsnet.Receiver
 	routingserver mockrouting.Server
 	delay         delay.D
+	conns         map[string]struct{}
 }
 
 func (n *network) Adapter(p testutil.Identity) bsnet.BitSwapNetwork {
@@ -149,7 +155,22 @@ func (nc *networkClient) ConnectTo(_ context.Context, p peer.ID) error {
 	if !nc.network.HasPeer(p) {
 		return errors.New("no such peer in network")
 	}
+	tag := tagForPeers(nc.local, p)
+	if _, ok := nc.network.conns[tag]; ok {
+		log.Warning("ALREADY CONNECTED TO PEER (is this a reconnect? test lib needs fixing)")
+		return nil
+	}
+	nc.network.conns[tag] = struct{}{}
+	// TODO: add handling for disconnects
+
 	nc.network.clients[p].PeerConnected(nc.local)
 	nc.Receiver.PeerConnected(p)
 	return nil
 }
+
+func tagForPeers(a, b peer.ID) string {
+	if a < b {
+		return string(a + b)
+	}
+	return string(b + a)
+}
diff --git a/exchange/bitswap/testutils.go b/exchange/bitswap/testutils.go
index 1b19bdd47df..1b1fcf20a13 100644
--- a/exchange/bitswap/testutils.go
+++ b/exchange/bitswap/testutils.go
@@ -59,7 +59,7 @@ func (g *SessionGenerator) Instances(n int) []Instance {
 	for i, inst := range instances {
 		for j := i + 1; j < len(instances); j++ {
 			oinst := instances[j]
-			inst.Exchange.PeerConnected(oinst.Peer)
+			inst.Exchange.network.ConnectTo(context.Background(), oinst.Peer)
 		}
 	}
 	return instances