Add events proxy interface

Signed-off-by: Derek McGowan <derek@mcg.dev>

client/client.go

@@ -29,7 +29,6 @@ import (
 	containersapi "github.com/containerd/containerd/v2/api/services/containers/v1"
 	contentapi "github.com/containerd/containerd/v2/api/services/content/v1"
 	diffapi "github.com/containerd/containerd/v2/api/services/diff/v1"
-	eventsapi "github.com/containerd/containerd/v2/api/services/events/v1"
 	imagesapi "github.com/containerd/containerd/v2/api/services/images/v1"
 	introspectionapi "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	leasesapi "github.com/containerd/containerd/v2/api/services/leases/v1"
@@ -43,6 +42,7 @@ import (
 	"github.com/containerd/containerd/v2/core/content"
 	contentproxy "github.com/containerd/containerd/v2/core/content/proxy"
 	"github.com/containerd/containerd/v2/core/events"
+	eventsproxy "github.com/containerd/containerd/v2/core/events/proxy"
 	"github.com/containerd/containerd/v2/core/images"
 	"github.com/containerd/containerd/v2/core/leases"
 	leasesproxy "github.com/containerd/containerd/v2/core/leases/proxy"
@@ -708,7 +708,7 @@ func (c *Client) EventService() EventService {
 	}
 	c.connMu.Lock()
 	defer c.connMu.Unlock()
-	return NewEventServiceFromClient(eventsapi.NewEventsClient(c.conn))
+	return eventsproxy.NewRemoteEvents(c.conn)
 }
 
 // SandboxStore returns the underlying sandbox store client

core/events/proxy/remote_events.go

@@ -0,0 +1,222 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package proxy
+
+import (
+	"context"
+	"fmt"
+
+	api "github.com/containerd/containerd/v2/api/services/events/v1"
+	"github.com/containerd/containerd/v2/api/types"
+	"github.com/containerd/containerd/v2/core/events"
+	"github.com/containerd/containerd/v2/protobuf"
+	"github.com/containerd/errdefs"
+	"github.com/containerd/ttrpc"
+	"github.com/containerd/typeurl/v2"
+	"google.golang.org/grpc"
+)
+
+type EventService interface {
+	events.Publisher
+	events.Forwarder
+	events.Subscriber
+}
+
+func NewRemoteEvents(client any) EventService {
+	switch c := client.(type) {
+	case api.EventsClient:
+		return &grpcEventsProxy{
+			client: c,
+		}
+	case api.TTRPCEventsClient:
+		return &ttrpcEventsProxy{
+			client: c,
+		}
+	case grpc.ClientConnInterface:
+		return &grpcEventsProxy{
+			client: api.NewEventsClient(c),
+		}
+	case *ttrpc.Client:
+		return &ttrpcEventsProxy{
+			client: api.NewTTRPCEventsClient(c),
+		}
+	default:
+		panic(fmt.Errorf("unsupported events client %T: %w", client, errdefs.ErrNotImplemented))
+	}
+}
+
+type grpcEventsProxy struct {
+	client api.EventsClient
+}
+
+func (p *grpcEventsProxy) Publish(ctx context.Context, topic string, event events.Event) error {
+	evt, err := typeurl.MarshalAny(event)
+	if err != nil {
+		return err
+	}
+	req := &api.PublishRequest{
+		Topic: topic,
+		Event: protobuf.FromAny(evt),
+	}
+	if _, err := p.client.Publish(ctx, req); err != nil {
+		return errdefs.FromGRPC(err)
+	}
+	return nil
+}
+
+func (p *grpcEventsProxy) Forward(ctx context.Context, envelope *events.Envelope) error {
+	req := &api.ForwardRequest{
+		Envelope: &types.Envelope{
+			Timestamp: protobuf.ToTimestamp(envelope.Timestamp),
+			Namespace: envelope.Namespace,
+			Topic:     envelope.Topic,
+			Event:     protobuf.FromAny(envelope.Event),
+		},
+	}
+	if _, err := p.client.Forward(ctx, req); err != nil {
+		return errdefs.FromGRPC(err)
+	}
+	return nil
+}
+
+func (p *grpcEventsProxy) Subscribe(ctx context.Context, filters ...string) (ch <-chan *events.Envelope, errs <-chan error) {
+	var (
+		evq  = make(chan *events.Envelope)
+		errq = make(chan error, 1)
+	)
+
+	errs = errq
+	ch = evq
+
+	session, err := p.client.Subscribe(ctx, &api.SubscribeRequest{
+		Filters: filters,
+	})
+	if err != nil {
+		errq <- err
+		close(errq)
+		return
+	}
+
+	go func() {
+		defer close(errq)
+
+		for {
+			ev, err := session.Recv()
+			if err != nil {
+				errq <- err
+				return
+			}
+
+			select {
+			case evq <- &events.Envelope{
+				Timestamp: protobuf.FromTimestamp(ev.Timestamp),
+				Namespace: ev.Namespace,
+				Topic:     ev.Topic,
+				Event:     ev.Event,
+			}:
+			case <-ctx.Done():
+				if cerr := ctx.Err(); cerr != context.Canceled {
+					errq <- cerr
+				}
+				return
+			}
+		}
+	}()
+
+	return ch, errs
+}
+
+type ttrpcEventsProxy struct {
+	client api.TTRPCEventsClient
+}
+
+func (p *ttrpcEventsProxy) Publish(ctx context.Context, topic string, event events.Event) error {
+	evt, err := typeurl.MarshalAny(event)
+	if err != nil {
+		return err
+	}
+	req := &api.PublishRequest{
+		Topic: topic,
+		Event: protobuf.FromAny(evt),
+	}
+	if _, err := p.client.Publish(ctx, req); err != nil {
+		return errdefs.FromGRPC(err)
+	}
+	return nil
+}
+
+func (p *ttrpcEventsProxy) Forward(ctx context.Context, envelope *events.Envelope) error {
+	req := &api.ForwardRequest{
+		Envelope: &types.Envelope{
+			Timestamp: protobuf.ToTimestamp(envelope.Timestamp),
+			Namespace: envelope.Namespace,
+			Topic:     envelope.Topic,
+			Event:     protobuf.FromAny(envelope.Event),
+		},
+	}
+	if _, err := p.client.Forward(ctx, req); err != nil {
+		return errdefs.FromGRPC(err)
+	}
+	return nil
+}
+
+func (p *ttrpcEventsProxy) Subscribe(ctx context.Context, filters ...string) (ch <-chan *events.Envelope, errs <-chan error) {
+	var (
+		evq  = make(chan *events.Envelope)
+		errq = make(chan error, 1)
+	)
+
+	errs = errq
+	ch = evq
+
+	session, err := p.client.Subscribe(ctx, &api.SubscribeRequest{
+		Filters: filters,
+	})
+	if err != nil {
+		errq <- err
+		close(errq)
+		return
+	}
+
+	go func() {
+		defer close(errq)
+
+		for {
+			ev, err := session.Recv()
+			if err != nil {
+				errq <- err
+				return
+			}
+
+			select {
+			case evq <- &events.Envelope{
+				Timestamp: protobuf.FromTimestamp(ev.Timestamp),
+				Namespace: ev.Namespace,
+				Topic:     ev.Topic,
+				Event:     ev.Event,
+			}:
+			case <-ctx.Done():
+				if cerr := ctx.Err(); cerr != context.Canceled {
+					errq <- cerr
+				}
+				return
+			}
+		}
+	}()
+
+	return ch, errs
+}