autopilot+pilot: refactor connection logic out of OpenChannel

In this commit, we refactor the existing connection logic outside of the
ChanController's OpenChannel method. We do this as previously it was
possible for peers to stall us while attempting to connect to them. In
order to remedy this, we now attempt to connect the peer before tracking
them in our set of pending opens.

autopilot/agent_test.go

@@ -77,7 +77,6 @@ var _ AttachmentHeuristic = (*mockHeuristic)(nil)
 type openChanIntent struct {
 	target  *btcec.PublicKey
 	amt     btcutil.Amount
-	addrs   []net.Addr
 	private bool
 }
 
@@ -86,13 +85,12 @@ type mockChanController struct {
 	private         bool
 }
 
-func (m *mockChanController) OpenChannel(target *btcec.PublicKey, amt btcutil.Amount,
-	addrs []net.Addr) error {
+func (m *mockChanController) OpenChannel(target *btcec.PublicKey,
+	amt btcutil.Amount) error {
 
 	m.openChanSignals <- openChanIntent{
 		target:  target,
 		amt:     amt,
-		addrs:   addrs,
 		private: m.private,
 	}
 
@@ -142,6 +140,12 @@ func TestAgentChannelOpenSignal(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return 0, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -230,8 +234,8 @@ func TestAgentChannelOpenSignal(t *testing.T) {
 type mockFailingChanController struct {
 }
 
-func (m *mockFailingChanController) OpenChannel(target *btcec.PublicKey, amt btcutil.Amount,
-	addrs []net.Addr) error {
+func (m *mockFailingChanController) OpenChannel(target *btcec.PublicKey,
+	amt btcutil.Amount) error {
 	return errors.New("failure")
 }
 
@@ -276,6 +280,12 @@ func TestAgentChannelFailureSignal(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return 0, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -366,6 +376,12 @@ func TestAgentChannelCloseSignal(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return 0, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -490,6 +506,12 @@ func TestAgentBalanceUpdate(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return walletBalance, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -606,6 +628,12 @@ func TestAgentImmediateAttach(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return walletBalance, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -698,10 +726,6 @@ func TestAgentImmediateAttach(t *testing.T) {
 					self.SerializeCompressed(),
 					openChan.target.SerializeCompressed())
 			}
-			if len(openChan.addrs) != 1 {
-				t.Fatalf("should have single addr, instead have: %v",
-					len(openChan.addrs))
-			}
 		case <-time.After(time.Second * 10):
 			t.Fatalf("channel not opened in time")
 		}
@@ -743,6 +767,12 @@ func TestAgentPrivateChannels(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return walletBalance, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -869,6 +899,12 @@ func TestAgentPendingChannelState(t *testing.T) {
 		WalletBalance: func() (btcutil.Amount, error) {
 			return walletBalance, nil
 		},
+		ConnectToPeer: func(*btcec.PublicKey, []net.Addr) (bool, error) {
+			return false, nil
+		},
+		DisconnectPeer: func(*btcec.PublicKey) error {
+			return nil
+		},
 		Graph:           memGraph,
 		MaxPendingOpens: 10,
 	}
@@ -949,10 +985,6 @@ func TestAgentPendingChannelState(t *testing.T) {
 				nodeKey.SerializeCompressed(),
 				openChan.target.SerializeCompressed())
 		}
-		if len(openChan.addrs) != 1 {
-			t.Fatalf("should have single addr, instead have: %v",
-				len(openChan.addrs))
-		}
 	case <-time.After(time.Second * 10):
 		t.Fatalf("channel wasn't opened in time")
 	}