libnetwork/driverapi: make EventNotify optional

corhere · corhere · commit 844023f7942d · 2025-07-22T11:51:14.000-04:00
Overlay is the only driver which makes use of the EventNotify facility,
yet all other driver implementations are forced to provide a stub
implementation. Move the EventNotify and DecodeTableEntry methods into a
new optional TableWatcher interface and remove the stubs from all the
other drivers.

Signed-off-by: Cory Snider &lt;csnider@mirantis.com&gt;
diff --git a/daemon/libnetwork/agent.go b/daemon/libnetwork/agent.go
@@ -491,17 +491,19 @@ func (n *Network) Services() map[string]ServiceInfo {
 	// Walk through the driver's tables, have the driver decode the entries
 	// and return the tuple {ep ID, value}. value is a string that coveys
 	// relevant info about the endpoint.
-	for _, table := range n.driverTables {
-		if table.objType != driverapi.EndpointObject {
-			continue
-		}
-		for key, value := range agent.networkDB.GetTableByNetwork(table.name, nwID) {
-			epID, info := d.DecodeTableEntry(table.name, key, value.Value)
-			if ep, ok := eps[epID]; !ok {
-				log.G(context.TODO()).Errorf("Inconsistent driver and libnetwork state for endpoint %s", epID)
-			} else {
-				ep.info = info
-				eps[epID] = ep
+	if d, ok := d.(driverapi.TableWatcher); ok {
+		for _, table := range n.driverTables {
+			if table.objType != driverapi.EndpointObject {
+				continue
+			}
+			for key, value := range agent.networkDB.GetTableByNetwork(table.name, nwID) {
+				epID, info := d.DecodeTableEntry(table.name, key, value.Value)
+				if ep, ok := eps[epID]; !ok {
+					log.G(context.TODO()).Errorf("Inconsistent driver and libnetwork state for endpoint %s", epID)
+				} else {
+					ep.info = info
+					eps[epID] = ep
+				}
 			}
 		}
 	}
@@ -814,6 +816,11 @@ func (n *Network) handleDriverTableEvent(ev events.Event) {
 		log.G(context.TODO()).Errorf("Could not resolve driver %s while handling driver table event: %v", n.networkType, err)
 		return
 	}
+	ed, ok := d.(driverapi.TableWatcher)
+	if !ok {
+		log.G(context.TODO()).Errorf("Could not notify driver %s about table event: driver does not implement TableWatcher interface", n.networkType)
+		return
+	}
 
 	var (
 		etype driverapi.EventType
@@ -833,7 +840,7 @@ func (n *Network) handleDriverTableEvent(ev events.Event) {
 		etype = driverapi.Update
 	}
 
-	d.EventNotify(etype, n.ID(), event.Table, event.Key, value)
+	ed.EventNotify(etype, n.ID(), event.Table, event.Key, value)
 }
 
 func (c *Controller) handleNodeTableEvent(ev events.Event) {
diff --git a/daemon/libnetwork/cnmallocator/manager.go b/daemon/libnetwork/cnmallocator/manager.go
@@ -32,13 +32,6 @@ func (d *manager) CreateNetwork(ctx context.Context, id string, option map[strin
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *manager) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *manager) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *manager) DeleteNetwork(nid string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
diff --git a/daemon/libnetwork/driverapi/driverapi.go b/daemon/libnetwork/driverapi/driverapi.go
@@ -56,6 +56,15 @@ type Driver interface {
 	// Leave method is invoked when a Sandbox detaches from an endpoint.
 	Leave(nid, eid string) error
 
+	// Type returns the type of this driver, the network type this driver manages
+	Type() string
+
+	// IsBuiltIn returns true if it is a built-in driver
+	IsBuiltIn() bool
+}
+
+// TableWatcher is an optional interface for a network driver.
+type TableWatcher interface {
 	// EventNotify notifies the driver when a CRUD operation has
 	// happened on a table of its interest as soon as this node
 	// receives such an event in the gossip layer. This method is
@@ -71,12 +80,6 @@ type Driver interface {
 	// For example: overlay driver returns the VTEP IP of the host that has the endpoint
 	// which is shown in 'network inspect --verbose'
 	DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string)
-
-	// Type returns the type of this driver, the network type this driver manages
-	Type() string
-
-	// IsBuiltIn returns true if it is a built-in driver
-	IsBuiltIn() bool
 }
 
 // ExtConner is an optional interface for a network driver.
diff --git a/daemon/libnetwork/drivers/bridge/bridge_linux.go b/daemon/libnetwork/drivers/bridge/bridge_linux.go
@@ -705,13 +705,6 @@ func (d *driver) NetworkFree(id string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) GetSkipGwAlloc(opts options.Generic) (ipv4, ipv6 bool, _ error) {
 	// The network doesn't exist yet, so use a dummy id that's long enough to be
 	// truncated to a short-id (12 characters) and used in the bridge device name.
diff --git a/daemon/libnetwork/drivers/bridge/brmanager/brmanager.go b/daemon/libnetwork/drivers/bridge/brmanager/brmanager.go
@@ -32,13 +32,6 @@ func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) DeleteNetwork(nid string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
diff --git a/daemon/libnetwork/drivers/host/host.go b/daemon/libnetwork/drivers/host/host.go
@@ -31,13 +31,6 @@ func (d *driver) NetworkFree(id string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string]interface{}, nInfo driverapi.NetworkInfo, ipV4Data, ipV6Data []driverapi.IPAMData) error {
 	d.Lock()
 	defer d.Unlock()
diff --git a/daemon/libnetwork/drivers/ipvlan/ipvlan.go b/daemon/libnetwork/drivers/ipvlan/ipvlan.go
@@ -95,10 +95,3 @@ func (d *driver) Type() string {
 func (d *driver) IsBuiltIn() bool {
 	return true
 }
-
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
diff --git a/daemon/libnetwork/drivers/ipvlan/ivmanager/ivmanager.go b/daemon/libnetwork/drivers/ipvlan/ivmanager/ivmanager.go
@@ -32,13 +32,6 @@ func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) DeleteNetwork(nid string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
diff --git a/daemon/libnetwork/drivers/macvlan/macvlan.go b/daemon/libnetwork/drivers/macvlan/macvlan.go
@@ -89,10 +89,3 @@ func (d *driver) Type() string {
 func (d *driver) IsBuiltIn() bool {
 	return true
 }
-
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
diff --git a/daemon/libnetwork/drivers/macvlan/mvmanager/mvmanager.go b/daemon/libnetwork/drivers/macvlan/mvmanager/mvmanager.go
@@ -32,13 +32,6 @@ func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) DeleteNetwork(nid string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
diff --git a/daemon/libnetwork/drivers/null/null.go b/daemon/libnetwork/drivers/null/null.go
@@ -31,13 +31,6 @@ func (d *driver) NetworkFree(id string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string]interface{}, nInfo driverapi.NetworkInfo, ipV4Data, ipV6Data []driverapi.IPAMData) error {
 	d.Lock()
 	defer d.Unlock()
diff --git a/daemon/libnetwork/drivers/overlay/overlay.go b/daemon/libnetwork/drivers/overlay/overlay.go
@@ -25,8 +25,10 @@ const (
 	secureOption = "encrypted"
 )
 
-// overlay driver must implement the discover-API.
-var _ discoverapi.Discover = (*driver)(nil)
+var (
+	_ discoverapi.Discover   = (*driver)(nil)
+	_ driverapi.TableWatcher = (*driver)(nil)
+)
 
 type driver struct {
 	// Immutable; mu does not need to be held when accessing these fields.
diff --git a/daemon/libnetwork/drivers/overlay/ovmanager/ovmanager.go b/daemon/libnetwork/drivers/overlay/ovmanager/ovmanager.go
@@ -167,13 +167,6 @@ func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string
 	return types.NotImplementedErrorf("not implemented")
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) DeleteNetwork(nid string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
diff --git a/daemon/libnetwork/drivers/remote/driver.go b/daemon/libnetwork/drivers/remote/driver.go
@@ -174,13 +174,6 @@ func (d *driver) NetworkFree(id string) error {
 	return d.call("FreeNetwork", fr, &api.FreeNetworkResponse{})
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) CreateNetwork(ctx context.Context, id string, options map[string]interface{}, nInfo driverapi.NetworkInfo, ipV4Data, ipV6Data []driverapi.IPAMData) error {
 	create := &api.CreateNetworkRequest{
 		NetworkID: id,
diff --git a/daemon/libnetwork/drivers/windows/overlay/overlay_windows.go b/daemon/libnetwork/drivers/windows/overlay/overlay_windows.go
@@ -19,6 +19,8 @@ const (
 	NetworkType = "overlay"
 )
 
+var _ driverapi.TableWatcher = (*driver)(nil)
+
 type driver struct {
 	networks networkTable
 	sync.Mutex
diff --git a/daemon/libnetwork/drivers/windows/windows.go b/daemon/libnetwork/drivers/windows/windows.go
@@ -305,13 +305,6 @@ func (ncfg *networkConfiguration) processIPAM(id string, ipamV4Data, ipamV6Data
 	return nil
 }
 
-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}
-
 func (d *driver) createNetwork(config *networkConfiguration) *hnsNetwork {
 	network := &hnsNetwork{
 		id:         config.ID,
diff --git a/daemon/libnetwork/libnetwork_internal_test.go b/daemon/libnetwork/libnetwork_internal_test.go
@@ -831,10 +831,3 @@ func (b *badDriver) NetworkAllocate(id string, option map[string]string, ipV4Dat
 func (b *badDriver) NetworkFree(id string) error {
 	return types.NotImplementedErrorf("not implemented")
 }
-
-func (b *badDriver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
-}
-
-func (b *badDriver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
-	return "", nil
-}

Original file line number	Diff line number	Diff line change
`@@ -32,13 +32,6 @@ func (d *manager) CreateNetwork(ctx context.Context, id string, option map[strin`
`32`	`32`	`return types.NotImplementedErrorf("not implemented")`
`33`	`33`	`}`
`34`	`34`
`35`		`-func (d *manager) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {`
`36`		`-}`
`37`		`-`
`38`		`-func (d *manager) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {`
`39`		`- return "", nil`
`40`		`-}`
`41`		`-`
`42`	`35`	`func (d *manager) DeleteNetwork(nid string) error {`
`43`	`36`	`return types.NotImplementedErrorf("not implemented")`
`44`	`37`	`}`
Original file line number	Diff line number	Diff line change
`@@ -32,13 +32,6 @@ func (d *driver) CreateNetwork(ctx context.Context, id string, option map[string`
`32`	`32`	`return types.NotImplementedErrorf("not implemented")`
`33`	`33`	`}`
`34`	`34`
`35`		`-func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {`
`36`		`-}`
`37`		`-`
`38`		`-func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {`
`39`		`- return "", nil`
`40`		`-}`
`41`		`-`
`42`	`35`	`func (d *driver) DeleteNetwork(nid string) error {`
`43`	`36`	`return types.NotImplementedErrorf("not implemented")`
`44`	`37`	`}`