Add dialer for events service

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

runtime/v2/shim/dialer.go

@@ -0,0 +1,87 @@
+/*
+   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 shim
+
+import (
+	"net"
+	"sync"
+
+	v1 "github.com/containerd/containerd/api/services/ttrpc/events/v1"
+	"github.com/containerd/ttrpc"
+	"github.com/pkg/errors"
+)
+
+type dialConnect func() (net.Conn, error)
+
+var errDialerClosed = errors.New("events dialer is closed")
+
+func newDialier(newFn dialConnect) *dialer {
+	return &dialer{
+		newFn: newFn,
+	}
+}
+
+type dialer struct {
+	mu sync.Mutex
+
+	newFn   dialConnect
+	service v1.EventsService
+	conn    net.Conn
+	closed  bool
+}
+
+func (d *dialer) Get() (v1.EventsService, error) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	if d.closed {
+		return nil, errDialerClosed
+	}
+	if d.service == nil {
+		conn, err := d.newFn()
+		if err != nil {
+			return nil, err
+		}
+		d.conn = conn
+		d.service = v1.NewEventsClient(ttrpc.NewClient(conn))
+	}
+	return d.service, nil
+}
+
+func (d *dialer) Put(err error) {
+	if err != nil {
+		d.mu.Lock()
+		d.conn.Close()
+		d.service = nil
+		d.mu.Unlock()
+	}
+}
+
+func (d *dialer) Close() (err error) {
+	d.mu.Lock()
+	if d.closed {
+		return errDialerClosed
+	}
+	if d.conn != nil {
+		err = d.conn.Close()
+	}
+	d.service = nil
+	d.closed = true
+	d.mu.Unlock()
+
+	return err
+}

runtime/v2/shim/publisher.go

@@ -0,0 +1,87 @@
+/*
+   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 shim
+
+import (
+	"context"
+	"net"
+	"sync"
+	"time"
+
+	v1 "github.com/containerd/containerd/api/services/ttrpc/events/v1"
+	"github.com/containerd/containerd/events"
+	"github.com/containerd/containerd/namespaces"
+	"github.com/containerd/typeurl"
+)
+
+func newPublisher(address string) *remoteEventsPublisher {
+	return &remoteEventsPublisher{
+		dialer: newDialier(func() (net.Conn, error) {
+			return connect(address, dial)
+		}),
+		closed: make(chan struct{}),
+	}
+}
+
+type remoteEventsPublisher struct {
+	dialer *dialer
+	closed chan struct{}
+	closer sync.Once
+}
+
+func (l *remoteEventsPublisher) Done() <-chan struct{} {
+	return l.closed
+}
+
+func (l *remoteEventsPublisher) Close() (err error) {
+	err = l.dialer.Close()
+	l.closer.Do(func() {
+		close(l.closed)
+	})
+	return err
+}
+
+func (l *remoteEventsPublisher) Publish(ctx context.Context, topic string, event events.Event) error {
+	client, err := l.dialer.Get()
+	if err != nil {
+		return err
+	}
+	ns, err := namespaces.NamespaceRequired(ctx)
+	if err != nil {
+		return err
+	}
+	any, err := typeurl.MarshalAny(event)
+	if err != nil {
+		return err
+	}
+	if _, err := client.Forward(ctx, &v1.ForwardRequest{
+		Envelope: &v1.Envelope{
+			Timestamp: time.Now(),
+			Namespace: ns,
+			Topic:     topic,
+			Event:     any,
+		},
+	}); err != nil {
+		l.dialer.Put(err)
+		return err
+	}
+	return nil
+}
+
+func connect(address string, d func(string, time.Duration) (net.Conn, error)) (net.Conn, error) {
+	return d(address, 5*time.Second)
+}

runtime/v2/shim/shim.go

@@ -21,21 +21,17 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"net"
 	"os"
 	"runtime"
 	"runtime/debug"
 	"strings"
-	"sync"
 	"time"
 
-	v1 "github.com/containerd/containerd/api/services/ttrpc/events/v1"
 	"github.com/containerd/containerd/events"
 	"github.com/containerd/containerd/log"
 	"github.com/containerd/containerd/namespaces"
 	shimapi "github.com/containerd/containerd/runtime/v2/task"
 	"github.com/containerd/ttrpc"
-	"github.com/containerd/typeurl"
 	"github.com/gogo/protobuf/proto"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -165,18 +161,10 @@ func run(id string, initFunc Init, config Config) error {
 		}
 	}
 	address := fmt.Sprintf("%s.ttrpc", addressFlag)
-	conn, err := connect(address, dialer)
-	if err != nil {
-		return err
-	}
-	publisher := &remoteEventsPublisher{
-		address: address,
-		conn:    conn,
-		closed:  make(chan struct{}),
-	}
+
+	publisher := newPublisher(address)
 	defer publisher.Close()
 
-	publisher.client = v1.NewEventsClient(ttrpc.NewClient(conn))
 	if namespaceFlag == "" {
 		return fmt.Errorf("shim namespace cannot be empty")
 	}
@@ -310,47 +298,3 @@ func dumpStacks(logger *logrus.Entry) {
 	buf = buf[:stackSize]
 	logger.Infof("=== BEGIN goroutine stack dump ===\n%s\n=== END goroutine stack dump ===", buf)
 }
-
-type remoteEventsPublisher struct {
-	address string
-	conn    net.Conn
-	client  v1.EventsService
-	closed  chan struct{}
-	closer  sync.Once
-}
-
-func (l *remoteEventsPublisher) Done() <-chan struct{} {
-	return l.closed
-}
-
-func (l *remoteEventsPublisher) Close() (err error) {
-	l.closer.Do(func() {
-		err = l.conn.Close()
-		close(l.closed)
-	})
-	return err
-}
-
-func (l *remoteEventsPublisher) Publish(ctx context.Context, topic string, event events.Event) error {
-	ns, err := namespaces.NamespaceRequired(ctx)
-	if err != nil {
-		return err
-	}
-	any, err := typeurl.MarshalAny(event)
-	if err != nil {
-		return err
-	}
-	_, err = l.client.Forward(ctx, &v1.ForwardRequest{
-		Envelope: &v1.Envelope{
-			Timestamp: time.Now(),
-			Namespace: ns,
-			Topic:     topic,
-			Event:     any,
-		},
-	})
-	return err
-}
-
-func connect(address string, d func(string, time.Duration) (net.Conn, error)) (net.Conn, error) {
-	return d(address, 100*time.Second)
-}

runtime/v2/shim/shim_unix.go

@@ -94,7 +94,7 @@ func openLog(ctx context.Context, _ string) (io.Writer, error) {
 	return fifo.OpenFifo(ctx, "log", unix.O_WRONLY, 0700)
 }
 
-func dialer(address string, timeout time.Duration) (net.Conn, error) {
+func dial(address string, timeout time.Duration) (net.Conn, error) {
 	address = strings.TrimPrefix(address, "unix://")
 	return net.DialTimeout("unix", address, timeout)
 }

runtime/v2/shim/shim_windows.go

@@ -287,7 +287,7 @@ func openLog(ctx context.Context, id string) (io.Writer, error) {
 	return dswl, nil
 }
 
-func dialer(address string, timeout time.Duration) (net.Conn, error) {
+func dial(address string, timeout time.Duration) (net.Conn, error) {
 	var c net.Conn
 	var lastError error
 	timedOutError := errors.Errorf("timed out waiting for npipe %s", address)