logging: new mode -l passthrough

it allows to pass the current std streams down to the container.

conmon support: https://github.com/containers/conmon/pull/289

[NO TESTS NEEDED] it needs a new conmon.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

3 files changed, 23 insertions, 3 deletions

diff --git a/cmd/podman/common/completion.go b/cmd/podman/common/completion.go
index 90522438d..ea453a331 100644
--- a/cmd/podman/common/completion.go
+++ b/cmd/podman/common/completion.go
@@ -771,10 +771,13 @@ func AutocompleteImageVolume(cmd *cobra.Command, args []string, toComplete strin
 }
 
 // AutocompleteLogDriver - Autocomplete log-driver options.
-// -> "journald", "none", "k8s-file"
+// -> "journald", "none", "k8s-file", "passthrough"
 func AutocompleteLogDriver(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 	// don't show json-file
 	logDrivers := []string{define.JournaldLogging, define.NoLogging, define.KubernetesLogging}
+	if !registry.IsRemote() {
+		logDrivers = append(logDrivers, define.PassthroughLogging)
+	}
 	return logDrivers, cobra.ShellCompDirectiveNoFileComp
 }
 
diff --git a/cmd/podman/containers/create.go b/cmd/podman/containers/create.go
index 8b27de53e..2593b4c44 100644
--- a/cmd/podman/containers/create.go
+++ b/cmd/podman/containers/create.go
@@ -19,6 +19,7 @@ import (
 	"github.com/containers/podman/v3/pkg/specgen"
 	"github.com/containers/podman/v3/pkg/specgenutil"
 	"github.com/containers/podman/v3/pkg/util"
+	"github.com/mattn/go-isatty"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
@@ -161,7 +162,9 @@ func create(cmd *cobra.Command, args []string) error {
 		}
 	}
 
-	fmt.Println(report.Id)
+	if cliVals.LogDriver != define.PassthroughLogging {
+		fmt.Println(report.Id)
+	}
 	return nil
 }
 
@@ -188,6 +191,14 @@ func CreateInit(c *cobra.Command, vals entities.ContainerCreateOptions, isInfra
 			vals.UserNS = "private"
 		}
 	}
+	if cliVals.LogDriver == define.PassthroughLogging {
+		if isatty.IsTerminal(0) || isatty.IsTerminal(1) || isatty.IsTerminal(2) {
+			return vals, errors.New("the '--log-driver passthrough' option cannot be used on a TTY")
+		}
+		if registry.IsRemote() {
+			return vals, errors.New("the '--log-driver passthrough' option is not supported in remote mode")
+		}
+	}
 
 	if !isInfra {
 		if c.Flag("shm-size").Changed {
diff --git a/cmd/podman/containers/run.go b/cmd/podman/containers/run.go
index d14961829..071708b76 100644
--- a/cmd/podman/containers/run.go
+++ b/cmd/podman/containers/run.go
@@ -158,8 +158,13 @@ func run(cmd *cobra.Command, args []string) error {
 		runOpts.InputStream = nil
 	}
 
+	passthrough := cliVals.LogDriver == define.PassthroughLogging
+
 	// If attach is set, clear stdin/stdout/stderr and only attach requested
 	if cmd.Flag("attach").Changed {
+		if passthrough {
+			return errors.Wrapf(define.ErrInvalidArg, "cannot specify --attach with --log-driver=passthrough")
+		}
 		runOpts.OutputStream = nil
 		runOpts.ErrorStream = nil
 		if !cliVals.Interactive {
@@ -179,6 +184,7 @@ func run(cmd *cobra.Command, args []string) error {
 			}
 		}
 	}
+
 	cliVals.PreserveFDs = runOpts.PreserveFDs
 	s := specgen.NewSpecGenerator(imageName, cliVals.RootFS)
 	if err := specgenutil.FillOutSpecGen(s, &cliVals, args); err != nil {
@@ -200,7 +206,7 @@ func run(cmd *cobra.Command, args []string) error {
 		return err
 	}
 
-	if runOpts.Detach {
+	if runOpts.Detach && !passthrough {
 		fmt.Println(report.Id)
 		return nil
 	}