feat: global signal handling with context cancellation

Signed-off-by: Alano Terblanche <18033717+Benehiko@users.noreply.github.com>

cli/command/container/attach.go

@@ -105,7 +105,12 @@ func RunAttach(ctx context.Context, dockerCLI command.Cli, containerID string, o
 
 	if opts.Proxy && !c.Config.Tty {
 		sigc := notifyAllSignals()
-		go ForwardAllSignals(ctx, apiClient, containerID, sigc)
+		// since we're explicitly setting up signal handling here, and the daemon will
+		// get notified independently of the clients ctx cancellation, we use this context
+		// but without cancellation to avoid ForwardAllSignals from returning
+		// before all signals are forwarded.
+		bgCtx := context.WithoutCancel(ctx)
+		go ForwardAllSignals(bgCtx, apiClient, containerID, sigc)
 		defer signal.StopCatch(sigc)
 	}
 

cli/command/container/client_test.go

@@ -37,6 +37,7 @@ type fakeClient struct {
 	containerRemoveFunc     func(ctx context.Context, containerID string, options container.RemoveOptions) error
 	containerKillFunc       func(ctx context.Context, containerID, signal string) error
 	containerPruneFunc      func(ctx context.Context, pruneFilters filters.Args) (types.ContainersPruneReport, error)
+	containerAttachFunc     func(ctx context.Context, containerID string, options container.AttachOptions) (types.HijackedResponse, error)
 	Version                 string
 }
 
@@ -173,3 +174,10 @@ func (f *fakeClient) ContainersPrune(ctx context.Context, pruneFilters filters.A
 	}
 	return types.ContainersPruneReport{}, nil
 }
+
+func (f *fakeClient) ContainerAttach(ctx context.Context, containerID string, options container.AttachOptions) (types.HijackedResponse, error) {
+	if f.containerAttachFunc != nil {
+		return f.containerAttachFunc(ctx, containerID, options)
+	}
+	return types.HijackedResponse{}, nil
+}

cli/command/container/run.go

@@ -150,7 +150,12 @@ func runContainer(ctx context.Context, dockerCli command.Cli, runOpts *runOption
 	}
 	if runOpts.sigProxy {
 		sigc := notifyAllSignals()
-		go ForwardAllSignals(ctx, apiClient, containerID, sigc)
+		// since we're explicitly setting up signal handling here, and the daemon will
+		// get notified independently of the clients ctx cancellation, we use this context
+		// but without cancellation to avoid ForwardAllSignals from returning
+		// before all signals are forwarded.
+		bgCtx := context.WithoutCancel(ctx)
+		go ForwardAllSignals(bgCtx, apiClient, containerID, sigc)
 		defer signal.StopCatch(sigc)
 	}
 

cli/command/container/run_test.go

@@ -5,11 +5,18 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
+	"os/signal"
+	"syscall"
 	"testing"
+	"time"
 
+	"github.com/creack/pty"
 	"github.com/docker/cli/cli"
+	"github.com/docker/cli/cli/streams"
 	"github.com/docker/cli/internal/test"
 	"github.com/docker/cli/internal/test/notary"
+	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/network"
 	specs "github.com/opencontainers/image-spec/specs-go/v1"
@@ -32,6 +39,68 @@ func TestRunLabel(t *testing.T) {
 	assert.NilError(t, cmd.Execute())
 }
 
+func TestRunAttachTermination(t *testing.T) {
+	p, tty, err := pty.Open()
+	assert.NilError(t, err)
+
+	defer func() {
+		_ = tty.Close()
+		_ = p.Close()
+	}()
+
+	killCh := make(chan struct{})
+	attachCh := make(chan struct{})
+	fakeCLI := test.NewFakeCli(&fakeClient{
+		createContainerFunc: func(_ *container.Config, _ *container.HostConfig, _ *network.NetworkingConfig, _ *specs.Platform, _ string) (container.CreateResponse, error) {
+			return container.CreateResponse{
+				ID: "id",
+			}, nil
+		},
+		containerKillFunc: func(ctx context.Context, containerID, signal string) error {
+			killCh <- struct{}{}
+			return nil
+		},
+		containerAttachFunc: func(ctx context.Context, containerID string, options container.AttachOptions) (types.HijackedResponse, error) {
+			server, client := net.Pipe()
+			t.Cleanup(func() {
+				_ = server.Close()
+			})
+			attachCh <- struct{}{}
+			return types.NewHijackedResponse(client, types.MediaTypeRawStream), nil
+		},
+		Version: "1.36",
+	}, func(fc *test.FakeCli) {
+		fc.SetOut(streams.NewOut(tty))
+		fc.SetIn(streams.NewIn(tty))
+	})
+	ctx, cancel := signal.NotifyContext(context.Background(), syscall.SIGTERM)
+	defer cancel()
+
+	assert.Equal(t, fakeCLI.In().IsTerminal(), true)
+	assert.Equal(t, fakeCLI.Out().IsTerminal(), true)
+
+	cmd := NewRunCommand(fakeCLI)
+	cmd.SetArgs([]string{"-it", "busybox"})
+	cmd.SilenceUsage = true
+	go func() {
+		assert.ErrorIs(t, cmd.ExecuteContext(ctx), context.Canceled)
+	}()
+
+	select {
+	case <-time.After(5 * time.Second):
+		t.Fatal("containerAttachFunc was not called before the 5 second timeout")
+	case <-attachCh:
+	}
+
+	assert.NilError(t, syscall.Kill(syscall.Getpid(), syscall.SIGTERM))
+	select {
+	case <-time.After(5 * time.Second):
+		cancel()
+		t.Fatal("containerKillFunc was not called before the 5 second timeout")
+	case <-killCh:
+	}
+}
+
 func TestRunCommandWithContentTrustErrors(t *testing.T) {
 	testCases := []struct {
 		name          string

cli/command/container/start.go

@@ -87,7 +87,8 @@ func RunStart(ctx context.Context, dockerCli command.Cli, opts *StartOptions) er
 		// We always use c.ID instead of container to maintain consistency during `docker start`
 		if !c.Config.Tty {
 			sigc := notifyAllSignals()
-			go ForwardAllSignals(ctx, dockerCli.Client(), c.ID, sigc)
+			bgCtx := context.WithoutCancel(ctx)
+			go ForwardAllSignals(bgCtx, dockerCli.Client(), c.ID, sigc)
 			defer signal.StopCatch(sigc)
 		}