Set syslog for exit commands on log-level=debug

We have a flag, --syslog, for telling logrus to log to syslog as
well as to the terminal. Previously, this flag also set the exit
command for containers to use `--syslog` (otherwise all output
from exit commands is lost). I attempted to replicate this with
Podman v2.0, but quickly ran into circular import hell (the flag
is defined in cmd/podman, I needed it in cmd/podman/containers,
cmd/podman imports cmd/podman/containers already, etc). Instead,
let's just set the syslog flag automatically on
`--log-level=debug` so we log exit commands automatically when
debug-level logs are requested. This is consistent with Conmon
and seems to make sense.

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

pkg/api/handlers/compat/exec.go

@@ -62,7 +62,8 @@ func ExecCreateHandler(w http.ResponseWriter, r *http.Request) {
 		utils.InternalServerError(w, err)
 		return
 	}
-	exitCommandArgs, err := generate.CreateExitCommandArgs(storageConfig, runtimeConfig, false, true, true)
+	// Automatically log to syslog if the server has log-level=debug set
+	exitCommandArgs, err := generate.CreateExitCommandArgs(storageConfig, runtimeConfig, logrus.IsLevelEnabled(logrus.DebugLevel), true, true)
 	if err != nil {
 		utils.InternalServerError(w, err)
 		return

pkg/specgen/generate/container_create.go

@@ -114,8 +114,7 @@ func MakeContainer(ctx context.Context, rt *libpod.Runtime, s *specgen.SpecGener
 	}
 	options = append(options, opts...)
 
-	// TODO: Enable syslog support - we'll need to put this in SpecGen.
-	exitCommandArgs, err := CreateExitCommandArgs(rt.StorageConfig(), rtc, false, s.Remove, false)
+	exitCommandArgs, err := CreateExitCommandArgs(rt.StorageConfig(), rtc, logrus.IsLevelEnabled(logrus.DebugLevel), s.Remove, false)
 	if err != nil {
 		return nil, err
 	}

pkg/specgen/specgen.go

@@ -129,7 +129,7 @@ type ContainerBasicConfig struct {
 	Sysctl map[string]string `json:"sysctl,omitempty"`
 	// Remove indicates if the container should be removed once it has been started
 	// and exits
-	Remove bool `json:"remove"`
+	Remove bool `json:"remove,omitempty"`
 	// PreserveFDs is a number of additional file descriptors (in addition
 	// to 0, 1, 2) that will be passed to the executed process. The total FDs
 	// passed will be 3 + PreserveFDs.