libnetwork/netutils: drop ElectInterfaceAddresses

The function references global shared, mutable state and is no longer
needed. Deleting it brings us one step closer to getting rid of that
pesky shared state.

Signed-off-by: Cory Snider <csnider@mirantis.com>

libnetwork/drivers/bridge/bridge_test.go

@@ -13,6 +13,7 @@ import (
 	"testing"
 
 	"github.com/docker/docker/libnetwork/driverapi"
+	"github.com/docker/docker/libnetwork/ipamutils"
 	"github.com/docker/docker/libnetwork/iptables"
 	"github.com/docker/docker/libnetwork/netlabel"
 	"github.com/docker/docker/libnetwork/netutils"
@@ -169,13 +170,13 @@ func compareBindings(a, b []types.PortBinding) bool {
 
 func getIPv4Data(t *testing.T, iface string) []driverapi.IPAMData {
 	ipd := driverapi.IPAMData{AddressSpace: "full"}
-	nws, _, err := netutils.ElectInterfaceAddresses(iface)
+	nw, err := netutils.FindAvailableNetwork(ipamutils.GetLocalScopeDefaultNetworks())
 	if err != nil {
 		t.Fatal(err)
 	}
-	ipd.Pool = nws[0]
+	ipd.Pool = nw
 	// Set network gateway to X.X.X.1
-	ipd.Gateway = types.GetIPNetCopy(nws[0])
+	ipd.Gateway = types.GetIPNetCopy(nw)
 	ipd.Gateway.IP[len(ipd.Gateway.IP)-1] = 1
 	return []driverapi.IPAMData{ipd}
 }
@@ -1049,7 +1050,15 @@ func TestCreateWithExistingBridge(t *testing.T) {
 	genericOption := make(map[string]interface{})
 	genericOption[netlabel.GenericData] = netconfig
 
-	if err := d.CreateNetwork(brName, genericOption, nil, getIPv4Data(t, brName), nil); err != nil {
+	ipv4Data := []driverapi.IPAMData{{
+		AddressSpace: "full",
+		Pool:         types.GetIPNetCopy(addr.IPNet),
+		Gateway:      types.GetIPNetCopy(addr.IPNet),
+	}}
+	// Set network gateway to X.X.X.1
+	ipv4Data[0].Gateway.IP[len(ipv4Data[0].Gateway.IP)-1] = 1
+
+	if err := d.CreateNetwork(brName, genericOption, nil, ipv4Data, nil); err != nil {
 		t.Fatalf("Failed to create bridge network: %v", err)
 	}
 

libnetwork/netutils/utils_linux.go

@@ -9,7 +9,6 @@ import (
 	"net"
 	"os"
 
-	"github.com/docker/docker/libnetwork/ipamutils"
 	"github.com/docker/docker/libnetwork/ns"
 	"github.com/docker/docker/libnetwork/resolvconf"
 	"github.com/docker/docker/libnetwork/types"
@@ -61,46 +60,6 @@ func GenerateIfaceName(nlh *netlink.Handle, prefix string, len int) (string, err
 	return "", types.InternalErrorf("could not generate interface name")
 }
 
-// ElectInterfaceAddresses looks for an interface on the OS with the
-// specified name and returns returns all its IPv4 and IPv6 addresses in CIDR notation.
-// If a failure in retrieving the addresses or no IPv4 address is found, an error is returned.
-// If the interface does not exist, it chooses from a predefined
-// list the first IPv4 address which does not conflict with other
-// interfaces on the system.
-func ElectInterfaceAddresses(name string) ([]*net.IPNet, []*net.IPNet, error) {
-	var v4Nets, v6Nets []*net.IPNet
-
-	link, _ := ns.NlHandle().LinkByName(name)
-	if link != nil {
-		v4addr, err := ns.NlHandle().AddrList(link, netlink.FAMILY_V4)
-		if err != nil {
-			return nil, nil, err
-		}
-		v6addr, err := ns.NlHandle().AddrList(link, netlink.FAMILY_V6)
-		if err != nil {
-			return nil, nil, err
-		}
-		for _, nlAddr := range v4addr {
-			v4Nets = append(v4Nets, nlAddr.IPNet)
-		}
-		for _, nlAddr := range v6addr {
-			v6Nets = append(v6Nets, nlAddr.IPNet)
-		}
-	}
-
-	if link == nil || len(v4Nets) == 0 {
-		// Choose from predefined local scope networks
-		v4Net, err := FindAvailableNetwork(ipamutils.PredefinedLocalScopeDefaultNetworks)
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "PredefinedLocalScopeDefaultNetworks List: %+v",
-				ipamutils.PredefinedLocalScopeDefaultNetworks)
-		}
-		v4Nets = append(v4Nets, v4Net)
-	}
-
-	return v4Nets, v6Nets, nil
-}
-
 // FindAvailableNetwork returns a network from the passed list which does not
 // overlap with existing interfaces in the system
 func FindAvailableNetwork(list []*net.IPNet) (*net.IPNet, error) {

libnetwork/netutils/utils_linux_test.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"net"
-	"sort"
 	"strings"
 	"testing"
 
@@ -300,66 +299,6 @@ func TestNetworkRequest(t *testing.T) {
 	}
 }
 
-func TestElectInterfaceAddressMultipleAddresses(t *testing.T) {
-	defer testutils.SetupTestOSContext(t)()
-
-	nws := []string{"172.101.202.254/16", "172.102.202.254/16"}
-	createInterface(t, "test", nws...)
-
-	ipv4NwList, ipv6NwList, err := ElectInterfaceAddresses("test")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if len(ipv4NwList) == 0 {
-		t.Fatal("unexpected empty ipv4 network addresses")
-	}
-
-	if len(ipv6NwList) == 0 {
-		t.Fatal("unexpected empty ipv6 network addresses")
-	}
-
-	nwList := []string{}
-	for _, ipv4Nw := range ipv4NwList {
-		nwList = append(nwList, ipv4Nw.String())
-	}
-	sort.Strings(nws)
-	sort.Strings(nwList)
-
-	if len(nws) != len(nwList) {
-		t.Fatalf("expected %v. got %v", nws, nwList)
-	}
-	for i, nw := range nws {
-		if nw != nwList[i] {
-			t.Fatalf("expected %v. got %v", nw, nwList[i])
-		}
-	}
-}
-
-func TestElectInterfaceAddress(t *testing.T) {
-	defer testutils.SetupTestOSContext(t)()
-
-	nws := "172.101.202.254/16"
-	createInterface(t, "test", nws)
-
-	ipv4Nw, ipv6Nw, err := ElectInterfaceAddresses("test")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if len(ipv4Nw) == 0 {
-		t.Fatal("unexpected empty ipv4 network addresses")
-	}
-
-	if len(ipv6Nw) == 0 {
-		t.Fatal("unexpected empty ipv6 network addresses")
-	}
-
-	if nws != ipv4Nw[0].String() {
-		t.Fatalf("expected %s. got %s", nws, ipv4Nw[0])
-	}
-}
-
 func createInterface(t *testing.T, name string, nws ...string) {
 	// Add interface
 	link := &netlink.Bridge{