libnetwork/driverapi: make discoverAPI an optional part of the interface

Most drivers do not implement this, so detect if a driver implements
the discoverAPI, and remove the implementation from drivers that do
not support it.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

libnetwork/agent.go

@@ -182,8 +182,11 @@ func (c *Controller) handleKeyChange(keys []*types.EncryptionKey) error {
 	}
 
 	c.drvRegistry.WalkDrivers(func(name string, driver driverapi.Driver, capability driverapi.Capability) bool {
-		err := driver.DiscoverNew(discoverapi.EncryptionKeysUpdate, drvEnc)
-		if err != nil {
+		dr, ok := driver.(discoverapi.Discover)
+		if !ok {
+			return false
+		}
+		if err := dr.DiscoverNew(discoverapi.EncryptionKeysUpdate, drvEnc); err != nil {
 			log.G(context.TODO()).Warnf("Failed to update datapath keys in driver %s: %v", name, err)
 			// Attempt to reconfigure keys in case of a update failure
 			// which can arise due to a mismatch of keys
@@ -191,7 +194,7 @@ func (c *Controller) handleKeyChange(keys []*types.EncryptionKey) error {
 			log.G(context.TODO()).Warnf("Reconfiguring datapath keys for  %s", name)
 			drvCfgEnc := discoverapi.DriverEncryptionConfig{}
 			drvCfgEnc.Keys, drvCfgEnc.Tags = c.getKeys(subsysIPSec)
-			err = driver.DiscoverNew(discoverapi.EncryptionKeysConfig, drvCfgEnc)
+			err = dr.DiscoverNew(discoverapi.EncryptionKeysConfig, drvCfgEnc)
 			if err != nil {
 				log.G(context.TODO()).Warnf("Failed to reset datapath keys in driver %s: %v", name, err)
 			}
@@ -232,7 +235,9 @@ func (c *Controller) agentSetup(clusterProvider cluster.Provider) error {
 		}
 		c.drvRegistry.WalkDrivers(func(name string, driver driverapi.Driver, capability driverapi.Capability) bool {
 			if capability.ConnectivityScope == datastore.GlobalScope {
-				c.agentDriverNotify(driver)
+				if d, ok := driver.(discoverapi.Discover); ok {
+					c.agentDriverNotify(d)
+				}
 			}
 			return false
 		})
@@ -337,9 +342,10 @@ func (c *Controller) agentInit(listenAddr, bindAddrOrInterface, advertiseAddr, d
 	drvEnc.Tags = tags
 
 	c.drvRegistry.WalkDrivers(func(name string, driver driverapi.Driver, capability driverapi.Capability) bool {
-		err := driver.DiscoverNew(discoverapi.EncryptionKeysConfig, drvEnc)
-		if err != nil {
-			log.G(context.TODO()).Warnf("Failed to set datapath keys in driver %s: %v", name, err)
+		if dr, ok := driver.(discoverapi.Discover); ok {
+			if err := dr.DiscoverNew(discoverapi.EncryptionKeysConfig, drvEnc); err != nil {
+				log.G(context.TODO()).Warnf("Failed to set datapath keys in driver %s: %v", name, err)
+			}
 		}
 		return false
 	})
@@ -357,7 +363,7 @@ func (c *Controller) agentJoin(remoteAddrList []string) error {
 	return agent.networkDB.Join(remoteAddrList)
 }
 
-func (c *Controller) agentDriverNotify(d driverapi.Driver) {
+func (c *Controller) agentDriverNotify(d discoverapi.Discover) {
 	agent := c.getAgent()
 	if agent == nil {
 		return

libnetwork/controller.go

@@ -385,12 +385,14 @@ func (c *Controller) BuiltinIPAMDrivers() []string {
 
 func (c *Controller) processNodeDiscovery(nodes []net.IP, add bool) {
 	c.drvRegistry.WalkDrivers(func(name string, driver driverapi.Driver, capability driverapi.Capability) bool {
-		c.pushNodeDiscovery(driver, capability, nodes, add)
+		if d, ok := driver.(discoverapi.Discover); ok {
+			c.pushNodeDiscovery(d, capability, nodes, add)
+		}
 		return false
 	})
 }
 
-func (c *Controller) pushNodeDiscovery(d driverapi.Driver, cap driverapi.Capability, nodes []net.IP, add bool) {
+func (c *Controller) pushNodeDiscovery(d discoverapi.Discover, cap driverapi.Capability, nodes []net.IP, add bool) {
 	var self net.IP
 	// try swarm-mode config
 	if agent := c.getAgent(); agent != nil {
@@ -452,7 +454,9 @@ func (c *Controller) GetPluginGetter() plugingetter.PluginGetter {
 }
 
 func (c *Controller) RegisterDriver(networkType string, driver driverapi.Driver, capability driverapi.Capability) error {
-	c.agentDriverNotify(driver)
+	if d, ok := driver.(discoverapi.Discover); ok {
+		c.agentDriverNotify(d)
+	}
 	return nil
 }
 

libnetwork/driverapi/driverapi.go

@@ -1,18 +1,12 @@
 package driverapi
 
-import (
-	"net"
-
-	"github.com/docker/docker/libnetwork/discoverapi"
-)
+import "net"
 
 // NetworkPluginEndpointType represents the Endpoint Type used by Plugin system
 const NetworkPluginEndpointType = "NetworkDriver"
 
 // Driver is an interface that every plugin driver needs to implement.
 type Driver interface {
-	discoverapi.Discover
-
 	// NetworkAllocate invokes the driver method to allocate network
 	// specific resources passing network id and network specific config.
 	// It returns a key,value pair of network specific driver allocations

libnetwork/drivers/bridge/bridge.go

@@ -14,7 +14,6 @@ import (
 
 	"github.com/containerd/containerd/log"
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/iptables"
 	"github.com/docker/docker/libnetwork/netlabel"
@@ -1435,16 +1434,6 @@ func (d *driver) IsBuiltIn() bool {
 	return true
 }
 
-// DiscoverNew is a notification for a new discovery event, such as a new node joining a cluster
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-// DiscoverDelete is a notification for a discovery delete event, such as a node leaving a cluster
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
 func parseEndpointOptions(epOptions map[string]interface{}) (*endpointConfiguration, error) {
 	if epOptions == nil {
 		return nil, nil

libnetwork/drivers/bridge/brmanager/brmanager.go

@@ -2,7 +2,6 @@ package brmanager
 
 import (
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -70,14 +69,6 @@ func (d *driver) IsBuiltIn() bool {
 	return true
 }
 
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
 func (d *driver) ProgramExternalConnectivity(nid, eid string, options map[string]interface{}) error {
 	return types.NotImplementedErrorf("not implemented")
 }

libnetwork/drivers/host/host.go

@@ -4,7 +4,6 @@ import (
 	"sync"
 
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -92,13 +91,3 @@ func (d *driver) Type() string {
 func (d *driver) IsBuiltIn() bool {
 	return true
 }
-
-// DiscoverNew is a notification for a new discovery event, such as a new node joining a cluster
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-// DiscoverDelete is a notification for a discovery delete event, such as a node leaving a cluster
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}

libnetwork/drivers/ipvlan/ipvlan.go

@@ -8,7 +8,6 @@ import (
 	"sync"
 
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -104,16 +103,6 @@ func (d *driver) RevokeExternalConnectivity(nid, eid string) error {
 	return nil
 }
 
-// DiscoverNew is a notification for a new discovery event.
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-// DiscoverDelete is a notification for a discovery delete event.
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
 func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
 }
 

libnetwork/drivers/ipvlan/ivmanager/ivmanager.go

@@ -2,7 +2,6 @@ package ivmanager
 
 import (
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -70,14 +69,6 @@ func (d *driver) IsBuiltIn() bool {
 	return true
 }
 
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
 func (d *driver) ProgramExternalConnectivity(nid, eid string, options map[string]interface{}) error {
 	return types.NotImplementedErrorf("not implemented")
 }

libnetwork/drivers/macvlan/macvlan.go

@@ -8,7 +8,6 @@ import (
 	"sync"
 
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -98,16 +97,6 @@ func (d *driver) RevokeExternalConnectivity(nid, eid string) error {
 	return nil
 }
 
-// DiscoverNew is a notification for a new discovery event
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-// DiscoverDelete is a notification for a discovery delete event
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
 func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
 }
 

libnetwork/drivers/macvlan/mvmanager/mvmanager.go

@@ -2,7 +2,6 @@ package mvmanager
 
 import (
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -70,14 +69,6 @@ func (d *driver) IsBuiltIn() bool {
 	return true
 }
 
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
 func (d *driver) ProgramExternalConnectivity(nid, eid string, options map[string]interface{}) error {
 	return types.NotImplementedErrorf("not implemented")
 }

libnetwork/drivers/null/null.go

@@ -4,7 +4,6 @@ import (
 	"sync"
 
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -92,13 +91,3 @@ func (d *driver) Type() string {
 func (d *driver) IsBuiltIn() bool {
 	return true
 }
-
-// DiscoverNew is a notification for a new discovery event, such as a new node joining a cluster
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-// DiscoverDelete is a notification for a discovery delete event, such as a node leaving a cluster
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}

libnetwork/drivers/overlay/overlay.go

@@ -23,6 +23,9 @@ const (
 	secureOption = "encrypted"
 )
 
+// overlay driver must implement the discover-API.
+var _ discoverapi.Discover = (*driver)(nil)
+
 type driver struct {
 	bindAddress      string
 	advertiseAddress string

libnetwork/drivers/overlay/ovmanager/ovmanager.go

@@ -10,7 +10,6 @@ import (
 	"github.com/containerd/containerd/log"
 	"github.com/docker/docker/libnetwork/bitmap"
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/drivers/overlay/overlayutils"
 	"github.com/docker/docker/libnetwork/netlabel"
@@ -208,16 +207,6 @@ func (d *driver) IsBuiltIn() bool {
 	return true
 }
 
-// DiscoverNew is a notification for a new discovery event, such as a new node joining a cluster
-func (d *driver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
-// DiscoverDelete is a notification for a discovery delete event, such as a node leaving a cluster
-func (d *driver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return types.NotImplementedErrorf("not implemented")
-}
-
 func (d *driver) ProgramExternalConnectivity(nid, eid string, options map[string]interface{}) error {
 	return types.NotImplementedErrorf("not implemented")
 }

libnetwork/drivers/remote/driver.go

@@ -16,6 +16,9 @@ import (
 	"github.com/pkg/errors"
 )
 
+// remote driver must implement the discover-API.
+var _ discoverapi.Discover = (*driver)(nil)
+
 type driver struct {
 	endpoint    *plugins.Client
 	networkType string

libnetwork/ipams/null/null.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"net"
 
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/ipamapi"
 	"github.com/docker/docker/libnetwork/types"
 )
@@ -57,14 +56,6 @@ func (a *allocator) ReleaseAddress(poolID string, ip net.IP) error {
 	return nil
 }
 
-func (a *allocator) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-func (a *allocator) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
 func (a *allocator) IsBuiltIn() bool {
 	return true
 }

libnetwork/ipams/remote/remote.go

@@ -6,7 +6,6 @@ import (
 	"net"
 
 	"github.com/containerd/containerd/log"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/ipamapi"
 	"github.com/docker/docker/libnetwork/ipams/remote/api"
 	"github.com/docker/docker/libnetwork/types"
@@ -168,16 +167,6 @@ func (a *allocator) ReleaseAddress(poolID string, address net.IP) error {
 	return a.call("ReleaseAddress", req, res)
 }
 
-// DiscoverNew is a notification for a new discovery event, such as a new global datastore
-func (a *allocator) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-// DiscoverDelete is a notification for a discovery delete event, such as a node leaving a cluster
-func (a *allocator) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
 func (a *allocator) IsBuiltIn() bool {
 	return false
 }

libnetwork/libnetwork_internal_test.go

@@ -10,7 +10,6 @@ import (
 
 	"github.com/docker/docker/internal/testutils/netnsutils"
 	"github.com/docker/docker/libnetwork/datastore"
-	"github.com/docker/docker/libnetwork/discoverapi"
 	"github.com/docker/docker/libnetwork/driverapi"
 	"github.com/docker/docker/libnetwork/ipamapi"
 	"github.com/docker/docker/libnetwork/netlabel"
@@ -674,14 +673,6 @@ func (b *badDriver) Leave(nid, eid string) error {
 	return nil
 }
 
-func (b *badDriver) DiscoverNew(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
-func (b *badDriver) DiscoverDelete(dType discoverapi.DiscoveryType, data interface{}) error {
-	return nil
-}
-
 func (b *badDriver) Type() string {
 	return badDriverName
 }