Enable detached exec for remote

The biggest obstacle here was cleanup - we needed a way to remove
detached exec sessions after they exited, but there's no way to
tell if an exec session will be attached or detached when it's
created, and that's when we must add the exit command that would
do the removal. The solution was adding a delay to the exit
command (5 minutes), which gives sufficient time for attached
exec sessions to retrieve the exit code of the session after it
exits, but still guarantees that they will be removed, even for
detached sessions. This requires Conmon 2.0.17, which has the new
`--exit-delay` flag.

As part of the exit command rework, we can drop the hack we were
using to clean up exec sessions (remove them as part of inspect).
This is a lot cleaner, and I'm a lot happier about it.

Otherwise, this is just plumbing - we need a bindings call for
detached exec, and that needed to be added to the tunnel mode
backend for entities.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

2 files changed, 23 insertions, 7 deletions

diff --git a/pkg/domain/infra/abi/containers.go b/pkg/domain/infra/abi/containers.go
index e982c7c11..706fcec47 100644
--- a/pkg/domain/infra/abi/containers.go
+++ b/pkg/domain/infra/abi/containers.go
@@ -613,12 +613,11 @@ func (ic *ContainerEngine) ContainerExecDetached(ctx context.Context, nameOrId s
 	if err != nil {
 		return "", errors.Wrapf(err, "error retrieving Libpod configuration to build exec exit command")
 	}
-	podmanPath, err := os.Executable()
+	// TODO: Add some ability to toggle syslog
+	exitCommandArgs, err := generate.CreateExitCommandArgs(storageConfig, runtimeConfig, false, true, true)
 	if err != nil {
-		return "", errors.Wrapf(err, "error retrieving executable to build exec exit command")
+		return "", errors.Wrapf(err, "error constructing exit command for exec session")
 	}
-	// TODO: Add some ability to toggle syslog
-	exitCommandArgs := generate.CreateExitCommandArgs(storageConfig, runtimeConfig, podmanPath, false, true, true)
 	execConfig.ExitCommand = exitCommandArgs
 
 	// Create and start the exec session
diff --git a/pkg/domain/infra/tunnel/containers.go b/pkg/domain/infra/tunnel/containers.go
index e1c859e7c..af9d94293 100644
--- a/pkg/domain/infra/tunnel/containers.go
+++ b/pkg/domain/infra/tunnel/containers.go
@@ -376,7 +376,7 @@ func (ic *ContainerEngine) ContainerAttach(ctx context.Context, nameOrId string,
 	return containers.Attach(ic.ClientCxt, nameOrId, &options.DetachKeys, nil, bindings.PTrue, options.Stdin, options.Stdout, options.Stderr, nil)
 }
 
-func (ic *ContainerEngine) ContainerExec(ctx context.Context, nameOrId string, options entities.ExecOptions, streams define.AttachStreams) (int, error) {
+func makeExecConfig(options entities.ExecOptions) *handlers.ExecCreateConfig {
 	env := []string{}
 	for k, v := range options.Envs {
 		env = append(env, fmt.Sprintf("%s=%s", k, v))
@@ -395,6 +395,12 @@ func (ic *ContainerEngine) ContainerExec(ctx context.Context, nameOrId string, o
 	createConfig.WorkingDir = options.WorkDir
 	createConfig.Cmd = options.Cmd
 
+	return createConfig
+}
+
+func (ic *ContainerEngine) ContainerExec(ctx context.Context, nameOrId string, options entities.ExecOptions, streams define.AttachStreams) (int, error) {
+	createConfig := makeExecConfig(options)
+
 	sessionID, err := containers.ExecCreate(ic.ClientCxt, nameOrId, createConfig)
 	if err != nil {
 		return 125, err
@@ -412,8 +418,19 @@ func (ic *ContainerEngine) ContainerExec(ctx context.Context, nameOrId string, o
 	return inspectOut.ExitCode, nil
 }
 
-func (ic *ContainerEngine) ContainerExecDetached(ctx context.Context, nameOrID string, options entities.ExecOptions) (string, error) {
-	return "", errors.New("not implemented")
+func (ic *ContainerEngine) ContainerExecDetached(ctx context.Context, nameOrId string, options entities.ExecOptions) (string, error) {
+	createConfig := makeExecConfig(options)
+
+	sessionID, err := containers.ExecCreate(ic.ClientCxt, nameOrId, createConfig)
+	if err != nil {
+		return "", err
+	}
+
+	if err := containers.ExecStart(ic.ClientCxt, sessionID); err != nil {
+		return "", err
+	}
+
+	return sessionID, nil
 }
 
 func startAndAttach(ic *ContainerEngine, name string, detachKeys *string, input, output, errput *os.File) error { //nolint