@@ -1,8 +1,6 @@

 package bridge

 import (

-	"errors"

-	"fmt"

 	"net"

 	"strings"

 	"sync"

@@ -78,14 +76,14 @@ func (d *driver) Config(option interface{}) error {

 	defer d.Unlock()

 	if d.config != nil {

-		return fmt.Errorf("configuration already exists, simplebridge configuration can be applied only once")

+		return ErrConfigExists

 	}

 	switch opt := option.(type) {

 	case options.Generic:

 		opaqueConfig, err := options.GenerateFromModel(opt, &Configuration{})

 		if err != nil {

-			return fmt.Errorf("failed to generate driver config: %v", err)

+			return err

 		}

 		config = opaqueConfig.(*Configuration)

 	case *Configuration:

@@ -106,13 +104,13 @@ func (d *driver) CreateNetwork(id driverapi.UUID, option interface{}) error {

 	d.Lock()

 	if d.config == nil {

 		d.Unlock()

-		return fmt.Errorf("trying to create a network on a driver without valid config")

+		return ErrInvalidConfig

 	}

 	config := d.config

 	if d.network != nil {

 		d.Unlock()

-		return fmt.Errorf("network already exists, simplebridge can only have one network")

+		return ErrNetworkExists

 	}

 	d.network = &bridgeNetwork{id: id}

 	d.Unlock()

@@ -205,7 +203,7 @@ func (d *driver) DeleteNetwork(nid driverapi.UUID) error {

 	}

 	if n.endpoint != nil {

-		err = fmt.Errorf("Network %s has active endpoint %s", n.id, n.endpoint.id)

+		err = &ActiveEndpointsError{nid: string(n.id), eid: string(n.endpoint.id)}

 		return err

 	}

@@ -230,7 +228,7 @@ func (d *driver) CreateEndpoint(nid, eid driverapi.UUID, sboxKey string, epOptio

 	n.Lock()

 	if n.id != nid {

 		n.Unlock()

-		return nil, fmt.Errorf("invalid network id %s", nid)

+		return nil, InvalidNetworkIDError(nid)

 	}

 	if n.endpoint != nil {

@@ -338,7 +336,7 @@ func (d *driver) DeleteEndpoint(nid, eid driverapi.UUID) error {

 	n.Lock()

 	if n.id != nid {

 		n.Unlock()

-		return fmt.Errorf("invalid network id %s", nid)

+		return InvalidNetworkIDError(nid)

 	}

 	if n.endpoint == nil {

@@ -349,7 +347,7 @@ func (d *driver) DeleteEndpoint(nid, eid driverapi.UUID) error {

 	ep := n.endpoint

 	if ep.id != eid {

 		n.Unlock()

-		return fmt.Errorf("invalid endpoint id %s", eid)

+		return InvalidEndpointIDError(eid)

 	}

 	n.endpoint = nil

@@ -398,5 +396,5 @@ func generateIfaceName() (string, error) {

 			return "", err

 		}

 	}

-	return "", errors.New("Failed to find name for new interface")

+	return "", ErrIfaceName

 }

new file mode 100644

@@ -0,0 +1,138 @@

+package bridge

+

+import (

+	"errors"

+	"fmt"

+	"net"

+)

+

+var (

+	// ErrConfigExists error is returned when driver already has a config applied.

+	ErrConfigExists = errors.New("configuration already exists, simplebridge configuration can be applied only once")

+

+	// ErrInvalidConfig error is returned when a network is created on a driver without valid config.

+	ErrInvalidConfig = errors.New("trying to create a network on a driver without valid config")

+

+	// ErrNetworkExists error is returned when a network already exists and another network is created.

+	ErrNetworkExists = errors.New("network already exists, simplebridge can only have one network")

+

+	// ErrIfaceName error is returned when a new name could not be generated.

+	ErrIfaceName = errors.New("Failed to find name for new interface")

+

+	// ErrNoIPAddr error is returned when bridge has no IPv4 addrss configured.

+	ErrNoIPAddr = errors.New("Bridge has no IPv4 address configured")

+)

+

+// ActiveEndpointsError is returned when there are

+// already active endpoints in the network being deleted.

+type ActiveEndpointsError struct {

+	nid string

+	eid string

+}

+

+func (aee *ActiveEndpointsError) Error() string {

+	return fmt.Sprintf("Network %s has active endpoint %s", aee.nid, aee.eid)

+}

+

+// InvalidNetworkIDError is returned when the passed

+// network id for an existing network is not a known id.

+type InvalidNetworkIDError string

+

+func (inie InvalidNetworkIDError) Error() string {

+	return fmt.Sprintf("invalid network id %s", inie)

+}

+

+// InvalidEndpointIDError is returned when the passed

+// endpoint id for an existing endpoint is not a known id.

+type InvalidEndpointIDError string

+

+func (ieie InvalidEndpointIDError) Error() string {

+	return fmt.Sprintf("invalid endpoint id %s", ieie)

+}

+

+// NonDefaultBridgeExistError is returned when a non-default

+// bridge config is passed but it does not already exist.

+type NonDefaultBridgeExistError string

+

+func (ndbee NonDefaultBridgeExistError) Error() string {

+	return fmt.Sprintf("bridge device with non default name %s must be created manually", ndbee)

+}

+

+// FixedCIDRv4Error is returned when fixed-cidrv4 configuration

+// failed.

+type FixedCIDRv4Error struct {

+	net    *net.IPNet

+	subnet *net.IPNet

+	err    error

+}

+

+func (fcv4 *FixedCIDRv4Error) Error() string {

+	return fmt.Sprintf("Setup FixedCIDRv4 failed for subnet %s in %s: %v", fcv4.subnet, fcv4.net, fcv4.err)

+}

+

+// FixedCIDRv6Error is returned when fixed-cidrv6 configuration

+// failed.

+type FixedCIDRv6Error struct {

+	net *net.IPNet

+	err error

+}

+

+func (fcv6 *FixedCIDRv6Error) Error() string {

+	return fmt.Sprintf("Setup FixedCIDRv6 failed for subnet %s in %s: %v", fcv6.net, fcv6.net, fcv6.err)

+}

+

+type ipForwardCfgError bridgeInterface

+

+func (i *ipForwardCfgError) Error() string {

+	return fmt.Sprintf("Unexpected request to enable IP Forwarding for: %v", *i)

+}

+

+type ipTableCfgError string

+

+func (name ipTableCfgError) Error() string {

+	return fmt.Sprintf("Unexpected request to set IP tables for interface: %s", name)

+}

+

+// IPv4AddrRangeError is returned when a valid IP address range couldn't be found.

+type IPv4AddrRangeError string

+

+func (name IPv4AddrRangeError) Error() string {

+	return fmt.Sprintf("can't find an address range for interface %q", name)

+}

+

+// IPv4AddrAddError is returned when IPv4 address could not be added to the bridge.

+type IPv4AddrAddError struct {

+	ip  *net.IPNet

+	err error

+}

+

+func (ipv4 *IPv4AddrAddError) Error() string {

+	return fmt.Sprintf("Failed to add IPv4 address %s to bridge: %v", ipv4.ip, ipv4.err)

+}

+

+// IPv6AddrAddError is returned when IPv6 address could not be added to the bridge.

+type IPv6AddrAddError struct {

+	ip  *net.IPNet

+	err error

+}

+

+func (ipv6 *IPv6AddrAddError) Error() string {

+	return fmt.Sprintf("Failed to add IPv6 address %s to bridge: %v", ipv6.ip, ipv6.err)

+}

+

+// IPv4AddrNoMatchError is returned when the bridge's IPv4 address does not match configured.

+type IPv4AddrNoMatchError struct {

+	ip    net.IP

+	cfgIP net.IP

+}

+

+func (ipv4 *IPv4AddrNoMatchError) Error() string {

+	return fmt.Sprintf("Bridge IPv4 (%s) does not match requested configuration %s", ipv4.ip, ipv4.cfgIP)

+}

+

+// IPv6AddrNoMatchError is returned when the bridge's IPv6 address does not match configured.

+type IPv6AddrNoMatchError net.IPNet

+

+func (ipv6 *IPv6AddrNoMatchError) Error() string {

+	return fmt.Sprintf("Bridge IPv6 addresses do not match the expected bridge configuration %s", ipv6)

+}

@@ -1,8 +1,6 @@

 package bridge

 import (

-	"fmt"

-

 	log "github.com/Sirupsen/logrus"

 	"github.com/docker/docker/pkg/parsers/kernel"

 	"github.com/docker/libnetwork/netutils"

@@ -14,7 +12,7 @@ func setupDevice(config *Configuration, i *bridgeInterface) error {

 	// We only attempt to create the bridge when the requested device name is

 	// the default one.

 	if config.BridgeName != DefaultBridgeName && !config.AllowNonDefaultBridge {

-		return fmt.Errorf("bridge device with non default name %q must be created manually", config.BridgeName)

+		return NonDefaultBridgeExistError(config.BridgeName)

 	}

 	// Set the bridgeInterface netlink.Bridge.

@@ -3,7 +3,6 @@ package bridge

 import (

 	"bytes"

 	"net"

-	"strings"

 	"testing"

 	"github.com/docker/libnetwork/netutils"

@@ -36,8 +35,13 @@ func TestSetupNewNonDefaultBridge(t *testing.T) {

 	config := &Configuration{BridgeName: "test0"}

 	br := &bridgeInterface{}

-	if err := setupDevice(config, br); err == nil || !strings.Contains(err.Error(), "non default name") {

-		t.Fatalf("Expected bridge creation failure with \"non default name\", got: %v", err)

+	err := setupDevice(config, br)

+	if err == nil {

+		t.Fatal("Expected bridge creation failure with \"non default name\", succeeded")

+	}

+

+	if _, ok := err.(NonDefaultBridgeExistError); !ok {

+		t.Fatalf("Did not fail with expected error. Actual error: %v", err)

 	}

 }

@@ -1,10 +1,6 @@

 package bridge

-import (

-	"fmt"

-

-	log "github.com/Sirupsen/logrus"

-)

+import log "github.com/Sirupsen/logrus"

 func setupFixedCIDRv4(config *Configuration, i *bridgeInterface) error {

 	addrv4, _, err := i.addresses()

@@ -14,7 +10,7 @@ func setupFixedCIDRv4(config *Configuration, i *bridgeInterface) error {

 	log.Debugf("Using IPv4 subnet: %v", config.FixedCIDR)

 	if err := ipAllocator.RegisterSubnet(addrv4.IPNet, config.FixedCIDR); err != nil {

-		return fmt.Errorf("Setup FixedCIDRv4 failed for subnet %s in %s: %v", config.FixedCIDR, addrv4.IPNet, err)

+		return &FixedCIDRv4Error{subnet: config.FixedCIDR, net: addrv4.IPNet, err: err}

 	}

 	return nil

@@ -50,7 +50,13 @@ func TestSetupBadFixedCIDRv4(t *testing.T) {

 		t.Fatalf("Assign IPv4 to bridge failed: %v", err)

 	}

-	if err := setupFixedCIDRv4(config, br); err == nil {

+	err := setupFixedCIDRv4(config, br)

+	if err == nil {

 		t.Fatal("Setup bridge FixedCIDRv4 should have failed")

 	}

+

+	if _, ok := err.(*FixedCIDRv4Error); !ok {

+		t.Fatalf("Did not fail with expected error. Actual error: %v", err)

+	}

+

 }

@@ -1,15 +1,11 @@

 package bridge

-import (

-	"fmt"

-

-	log "github.com/Sirupsen/logrus"

-)

+import log "github.com/Sirupsen/logrus"

 func setupFixedCIDRv6(config *Configuration, i *bridgeInterface) error {

 	log.Debugf("Using IPv6 subnet: %v", config.FixedCIDRv6)

 	if err := ipAllocator.RegisterSubnet(config.FixedCIDRv6, config.FixedCIDRv6); err != nil {

-		return fmt.Errorf("Setup FixedCIDRv6 failed for subnet %s in %s: %v", config.FixedCIDRv6, config.FixedCIDRv6, err)

+		return &FixedCIDRv6Error{net: config.FixedCIDRv6, err: err}

 	}

 	return nil

@@ -13,7 +13,7 @@ const (

 func setupIPForwarding(config *Configuration, i *bridgeInterface) error {

 	// Sanity Check

 	if config.EnableIPForwarding == false {

-		return fmt.Errorf("Unexpected request to enable IP Forwarding for: %v", *i)

+		return (*ipForwardCfgError)(i)

 	}

 	// Enable IPv4 forwarding

@@ -3,7 +3,6 @@ package bridge

 import (

 	"bytes"

 	"io/ioutil"

-	"strings"

 	"testing"

 )

@@ -47,9 +46,12 @@ func TestUnexpectedSetupIPForwarding(t *testing.T) {

 	br := &bridgeInterface{}

 	// Attempt Set IP Forwarding

-	if err := setupIPForwarding(config, br); err == nil {

+	err := setupIPForwarding(config, br)

+	if err == nil {

 		t.Fatal("Setup IP forwarding was expected to fail")

-	} else if !strings.Contains(err.Error(), "Unexpected request") {

+	}

+

+	if _, ok := err.(*ipForwardCfgError); !ok {

 		t.Fatalf("Setup IP forwarding failed with unexpected error: %v", err)

 	}

 }

@@ -16,7 +16,7 @@ const (

 func setupIPTables(config *Configuration, i *bridgeInterface) error {

 	// Sanity check.

 	if config.EnableIPTables == false {

-		return fmt.Errorf("Unexpected request to set IP tables for interface: %s", config.BridgeName)

+		return ipTableCfgError(config.BridgeName)

 	}

 	addrv4, _, err := netutils.GetIfaceAddr(config.BridgeName)

@@ -1,7 +1,6 @@

 package bridge

 import (

-	"fmt"

 	"net"

 	log "github.com/Sirupsen/logrus"

@@ -49,7 +48,7 @@ func setupBridgeIPv4(config *Configuration, i *bridgeInterface) error {

 	log.Debugf("Creating bridge interface %q with network %s", config.BridgeName, bridgeIPv4)

 	if err := netlink.AddrAdd(i.Link, &netlink.Addr{IPNet: bridgeIPv4}); err != nil {

-		return fmt.Errorf("Failed to add IPv4 address %s to bridge: %v", bridgeIPv4, err)

+		return &IPv4AddrAddError{ip: bridgeIPv4, err: err}

 	}

 	i.bridgeIPv4 = bridgeIPv4

@@ -80,5 +79,5 @@ func electBridgeIPv4(config *Configuration) (*net.IPNet, error) {

 		}

 	}

-	return nil, fmt.Errorf("'t find an address range for interface %q", config.BridgeName)

+	return nil, IPv4AddrRangeError(config.BridgeName)

 }

@@ -30,7 +30,7 @@ func setupBridgeIPv6(config *Configuration, i *bridgeInterface) error {

 	}

 	if err := netlink.AddrAdd(i.Link, &netlink.Addr{IPNet: bridgeIPv6}); err != nil {

-		return fmt.Errorf("Failed to add IPv6 address %s to bridge: %v", bridgeIPv6, err)

+		return &IPv6AddrAddError{ip: bridgeIPv6, err: err}

 	}

 	i.bridgeIPv6 = bridgeIPv6

@@ -1,10 +1,6 @@

 package bridge

-import (

-	"fmt"

-

-	"github.com/vishvananda/netlink"

-)

+import "github.com/vishvananda/netlink"

 func setupVerifyAndReconcile(config *Configuration, i *bridgeInterface) error {

 	// Fetch a single IPv4 and a slice of IPv6 addresses from the bridge.

@@ -15,18 +11,18 @@ func setupVerifyAndReconcile(config *Configuration, i *bridgeInterface) error {

 	// Verify that the bridge does have an IPv4 address.

 	if addrv4.IPNet == nil {

-		return fmt.Errorf("Bridge has no IPv4 address configured")

+		return ErrNoIPAddr

 	}

 	// Verify that the bridge IPv4 address matches the requested configuration.

 	if config.AddressIPv4 != nil && !addrv4.IP.Equal(config.AddressIPv4.IP) {

-		return fmt.Errorf("Bridge IPv4 (%s) does not match requested configuration %s", addrv4.IP, config.AddressIPv4.IP)

+		return &IPv4AddrNoMatchError{ip: addrv4.IP, cfgIP: config.AddressIPv4.IP}

 	}

 	// Verify that one of the bridge IPv6 addresses matches the requested

 	// configuration.

 	if config.EnableIPv6 && !findIPv6Address(netlink.Addr{IPNet: bridgeIPv6}, addrsv6) {

-		return fmt.Errorf("Bridge IPv6 addresses do not match the expected bridge configuration %s", bridgeIPv6)

+		return (*IPv6AddrNoMatchError)(bridgeIPv6)

 	}

 	// By this time we have either configured a new bridge with an IP address