oci: use json formatted errors from the runtime

request json formatted error messages from the OCI runtime so that we
can nicely print them.

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

1 files changed, 16 insertions, 2 deletions

diff --git a/libpod/oci_linux.go b/libpod/oci_linux.go
index 7c1c18052..b9820ce9f 100644
--- a/libpod/oci_linux.go
+++ b/libpod/oci_linux.go
@@ -6,6 +6,7 @@ import (
 	"bufio"
 	"bytes"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -208,6 +209,9 @@ func (r *OCIRuntime) createOCIContainer(ctr *Container, cgroupParent string, res
 	defer parentPipe.Close()
 	defer parentStartPipe.Close()
 
+	ociLog := filepath.Join(ctr.state.RunDir, "oci-log")
+	logLevel := logrus.GetLevel()
+
 	args := []string{}
 	if r.cgroupManager == SystemdCgroupsManager {
 		args = append(args, "-s")
@@ -219,6 +223,9 @@ func (r *OCIRuntime) createOCIContainer(ctr *Container, cgroupParent string, res
 	args = append(args, "-b", ctr.bundlePath())
 	args = append(args, "-p", filepath.Join(ctr.state.RunDir, "pidfile"))
 	args = append(args, "--exit-dir", r.exitsDir)
+	if logLevel != logrus.DebugLevel {
+		args = append(args, "--runtime-arg", "--log-format=json", "--runtime-arg", "--log", fmt.Sprintf("--runtime-arg=%s", ociLog))
+	}
 	if ctr.config.ConmonPidFile != "" {
 		args = append(args, "--conmon-pidfile", ctr.config.ConmonPidFile)
 	}
@@ -248,7 +255,6 @@ func (r *OCIRuntime) createOCIContainer(ctr *Container, cgroupParent string, res
 		args = append(args, "--no-pivot")
 	}
 
-	logLevel := logrus.GetLevel()
 	args = append(args, "--log-level", logLevel.String())
 
 	if logLevel == logrus.DebugLevel {
@@ -417,8 +423,16 @@ func (r *OCIRuntime) createOCIContainer(ctr *Container, cgroupParent string, res
 		}
 		logrus.Debugf("Received container pid: %d", ss.si.Pid)
 		if ss.si.Pid == -1 {
+			data, err := ioutil.ReadFile(ociLog)
+			if err == nil {
+				var ociErr ociError
+				if err := json.Unmarshal(data, &ociErr); err == nil {
+					return errors.Wrapf(ErrOCIRuntime, "%s", strings.Trim(ociErr.Msg, "\n"))
+				}
+			}
+			// If we failed to parse the JSON errors, then print the output as it is
 			if ss.si.Message != "" {
-				return errors.Wrapf(ErrInternal, "container create failed: %s", ss.si.Message)
+				return errors.Wrapf(ErrOCIRuntime, "%s", ss.si.Message)
 			}
 			return errors.Wrapf(ErrInternal, "container create failed")
 		}