[#1632] node: Subscribe on the successful container creations/removals

There is a need to sync container-related caching mechanism with the
actual Sidechain changes. To do this, node should be able to listen
incoming notifications about container ops.

Define `PutSuccess` / `DeleteSuccess` notification event's parsers.
Subscribe to these events in node app. As initial implementation node
will log event receipts. Later handling is going to be practically
complicated.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

cmd/neofs-node/container.go

@@ -63,6 +63,18 @@ func initContainerService(c *cfg) {
 		neoClient: wrap,
 	}
 
+	subscribeToContainerCreation(c, func(e event.Event) {
+		c.log.Debug("container creation event's receipt",
+			zap.Stringer("id", e.(containerEvent.PutSuccess).ID),
+		)
+	})
+
+	subscribeToContainerRemoval(c, func(e event.Event) {
+		c.log.Debug("container removal event's receipt",
+			zap.Stringer("id", e.(containerEvent.DeleteSuccess).ID),
+		)
+	})
+
 	if c.cfgMorph.disableCache {
 		c.cfgObject.eaclSource = eACLFetcher
 		cnrRdr.eacl = eACLFetcher
@@ -195,6 +207,34 @@ func addContainerAsyncNotificationHandler(c *cfg, sTyp string, h event.Handler)
 	)
 }
 
+// stores already registered parsers of the notification events thrown by Container contract.
+// MUST NOT be used concurrently.
+var mRegisteredParsersContainer = make(map[string]struct{})
+
+// registers event parser by name once. MUST NOT be called concurrently.
+func registerEventParserOnceContainer(c *cfg, name string, p event.NotificationParser) {
+	if _, ok := mRegisteredParsersContainer[name]; !ok {
+		setContainerNotificationParser(c, name, p)
+		mRegisteredParsersContainer[name] = struct{}{}
+	}
+}
+
+// subscribes to successful container creation. Provided handler is called asynchronously
+// on corresponding routine pool. MUST NOT be called concurrently with itself and other
+// similar functions.
+func subscribeToContainerCreation(c *cfg, h event.Handler) {
+	const eventNameContainerCreated = "PutSuccess"
+	registerEventParserOnceContainer(c, eventNameContainerCreated, containerEvent.ParsePutSuccess)
+	addContainerAsyncNotificationHandler(c, eventNameContainerCreated, h)
+}
+
+// like subscribeToContainerCreation but for removal.
+func subscribeToContainerRemoval(c *cfg, h event.Handler) {
+	const eventNameContainerRemoved = "DeleteSuccess"
+	registerEventParserOnceContainer(c, eventNameContainerRemoved, containerEvent.ParseDeleteSuccess)
+	addContainerAsyncNotificationHandler(c, eventNameContainerRemoved, h)
+}
+
 func setContainerNotificationParser(c *cfg, sTyp string, p event.NotificationParser) {
 	typ := event.TypeFromString(sTyp)
 

pkg/morph/event/container/delete.go

@@ -7,6 +7,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
 	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
 	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
+	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
 )
 
 // Delete structure of container.Delete notification from morph chain.
@@ -81,3 +82,42 @@ func ParseDelete(e *state.ContainedNotificationEvent) (event.Event, error) {
 
 	return ev, nil
 }
+
+// DeleteSuccess structures notification event of successful container removal
+// thrown by Container contract.
+type DeleteSuccess struct {
+	// Identifier of the removed container.
+	ID cid.ID
+}
+
+// MorphEvent implements Neo:Morph Event interface.
+func (DeleteSuccess) MorphEvent() {}
+
+// ParseDeleteSuccess decodes notification event thrown by Container contract into
+// DeleteSuccess and returns it as event.Event.
+func ParseDeleteSuccess(e *state.ContainedNotificationEvent) (event.Event, error) {
+	items, err := event.ParseStackArray(e)
+	if err != nil {
+		return nil, fmt.Errorf("parse stack array from raw notification event: %w", err)
+	}
+
+	const expectedItemNumDeleteSuccess = 1
+
+	if ln := len(items); ln != expectedItemNumDeleteSuccess {
+		return nil, event.WrongNumberOfParameters(expectedItemNumDeleteSuccess, ln)
+	}
+
+	binID, err := client.BytesFromStackItem(items[0])
+	if err != nil {
+		return nil, fmt.Errorf("parse container ID item: %w", err)
+	}
+
+	var res DeleteSuccess
+
+	err = res.ID.Decode(binID)
+	if err != nil {
+		return nil, fmt.Errorf("decode container ID: %w", err)
+	}
+
+	return res, nil
+}

pkg/morph/event/container/delete_test.go

@@ -1,10 +1,12 @@
 package container
 
 import (
+	"crypto/sha256"
 	"testing"
 
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
+	cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
 	"github.com/stretchr/testify/require"
 )
 
@@ -67,3 +69,46 @@ func TestParseDelete(t *testing.T) {
 		}, ev)
 	})
 }
+
+func TestParseDeleteSuccess(t *testing.T) {
+	t.Run("wrong number of parameters", func(t *testing.T) {
+		prms := []stackitem.Item{
+			stackitem.NewMap(),
+			stackitem.NewMap(),
+		}
+
+		_, err := ParseDeleteSuccess(createNotifyEventFromItems(prms))
+		require.EqualError(t, err, event.WrongNumberOfParameters(1, len(prms)).Error())
+	})
+
+	t.Run("wrong container parameter", func(t *testing.T) {
+		_, err := ParseDeleteSuccess(createNotifyEventFromItems([]stackitem.Item{
+			stackitem.NewMap(),
+		}))
+
+		require.Error(t, err)
+
+		_, err = ParseDeleteSuccess(createNotifyEventFromItems([]stackitem.Item{
+			stackitem.NewByteArray([]byte{1, 2, 3}),
+		}))
+
+		require.Error(t, err)
+	})
+
+	t.Run("correct behavior", func(t *testing.T) {
+		id := cidtest.ID()
+
+		binID := make([]byte, sha256.Size)
+		id.Encode(binID)
+
+		ev, err := ParseDeleteSuccess(createNotifyEventFromItems([]stackitem.Item{
+			stackitem.NewByteArray(binID),
+		}))
+
+		require.NoError(t, err)
+
+		require.Equal(t, DeleteSuccess{
+			ID: id,
+		}, ev)
+	})
+}

pkg/morph/event/container/put.go

@@ -7,6 +7,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
 	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
 	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
+	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
 )
 
 // Put structure of container.Put notification from morph chain.
@@ -106,3 +107,47 @@ func ParsePut(e *state.ContainedNotificationEvent) (event.Event, error) {
 
 	return ev, nil
 }
+
+// PutSuccess structures notification event of successful container creation
+// thrown by Container contract.
+type PutSuccess struct {
+	// Identifier of the newly created container.
+	ID cid.ID
+}
+
+// MorphEvent implements Neo:Morph Event interface.
+func (PutSuccess) MorphEvent() {}
+
+// ParsePutSuccess decodes notification event thrown by Container contract into
+// PutSuccess and returns it as event.Event.
+func ParsePutSuccess(e *state.ContainedNotificationEvent) (event.Event, error) {
+	items, err := event.ParseStackArray(e)
+	if err != nil {
+		return nil, fmt.Errorf("parse stack array from raw notification event: %w", err)
+	}
+
+	const expectedItemNumPutSuccess = 2
+
+	if ln := len(items); ln != expectedItemNumPutSuccess {
+		return nil, event.WrongNumberOfParameters(expectedItemNumPutSuccess, ln)
+	}
+
+	binID, err := client.BytesFromStackItem(items[0])
+	if err != nil {
+		return nil, fmt.Errorf("parse container ID item: %w", err)
+	}
+
+	_, err = client.BytesFromStackItem(items[1])
+	if err != nil {
+		return nil, fmt.Errorf("parse public key item: %w", err)
+	}
+
+	var res PutSuccess
+
+	err = res.ID.Decode(binID)
+	if err != nil {
+		return nil, fmt.Errorf("decode container ID: %w", err)
+	}
+
+	return res, nil
+}

pkg/morph/event/container/put_test.go

@@ -1,10 +1,12 @@
 package container
 
 import (
+	"crypto/sha256"
 	"testing"
 
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
+	cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
 	"github.com/stretchr/testify/require"
 )
 
@@ -81,3 +83,50 @@ func TestParsePut(t *testing.T) {
 		}, ev)
 	})
 }
+
+func TestParsePutSuccess(t *testing.T) {
+	t.Run("wrong number of parameters", func(t *testing.T) {
+		prms := []stackitem.Item{
+			stackitem.NewMap(),
+		}
+
+		_, err := ParsePutSuccess(createNotifyEventFromItems(prms))
+		require.EqualError(t, err, event.WrongNumberOfParameters(2, len(prms)).Error())
+	})
+
+	t.Run("wrong container ID parameter", func(t *testing.T) {
+		_, err := ParsePutSuccess(createNotifyEventFromItems([]stackitem.Item{
+			stackitem.NewMap(),
+			stackitem.NewMap(),
+		}))
+
+		require.Error(t, err)
+	})
+
+	id := cidtest.ID()
+
+	binID := make([]byte, sha256.Size)
+	id.Encode(binID)
+
+	t.Run("wrong public key parameter", func(t *testing.T) {
+		_, err := ParsePutSuccess(createNotifyEventFromItems([]stackitem.Item{
+			stackitem.NewByteArray(binID),
+			stackitem.NewMap(),
+		}))
+
+		require.Error(t, err)
+	})
+
+	t.Run("correct behavior", func(t *testing.T) {
+		ev, err := ParsePutSuccess(createNotifyEventFromItems([]stackitem.Item{
+			stackitem.NewByteArray(binID),
+			stackitem.NewByteArray([]byte("key")),
+		}))
+
+		require.NoError(t, err)
+
+		require.Equal(t, PutSuccess{
+			ID: id,
+		}, ev)
+	})
+}