create: improve parser for --healthcheck-command

Fix Docker CLI compatibility issue: the "--healthcheck-command" option
value should not be split but instead be passed as single string to
"/bin/sh -c <opt>".

On the other hand implement the same extension as is already available
for "--entrypoint", i.e. allow the option value to be a JSON array of
strings. This will make life easier for tools like podman-compose.

Continuation of containers#3455 & containers#3507

cmd/podman/shared/create.go

@@ -26,7 +26,6 @@ import (
 	"github.com/docker/docker/pkg/signal"
 	"github.com/docker/go-connections/nat"
 	"github.com/docker/go-units"
-	"github.com/google/shlex"
 	"github.com/opencontainers/selinux/go-selinux/label"
 	"github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
@@ -788,9 +787,12 @@ func makeHealthCheckFromCli(c *GenericCLIResults) (*manifest.Schema2HealthConfig
 		return nil, errors.New("Must define a healthcheck command for all healthchecks")
 	}
 
-	cmd, err := shlex.Split(inCommand)
+	// first try to parse option value as JSON array of strings...
+	cmd := []string{}
+	err := json.Unmarshal([]byte(inCommand), &cmd)
 	if err != nil {
-		return nil, errors.Wrap(err, "failed to parse healthcheck command")
+		// ...otherwise pass it to "/bin/sh -c"
+		cmd = []string{"/bin/sh", "-c", inCommand}
 	}
 	hc := manifest.Schema2HealthConfig{
 		Test: cmd,

docs/podman-create.1.md

@@ -272,12 +272,14 @@ The following example maps uids 0-2000 in the container to the uids 30000-31999
 
 Add additional groups to run as
 
-**--healthcheck-command**=*command*
+**--healthcheck-command**=*"command"* | *'["command", "arg1", ...]'*
 
 Set or alter a healthcheck command for a container. The command is a command to be executed inside your
 container that determines your container health.  The command is required for other healthcheck options
 to be applied.  A value of `none` disables existing healthchecks.
 
+You need to specify multi option commands in the form of a json string.
+
 **--healthcheck-interval**=*interval*
 
 Set an interval for the healthchecks (a value of `disable` results in no automatic timer setup) (default "30s")

docs/podman-run.1.md

@@ -279,12 +279,14 @@ The example maps gids 0-2000 in the container to the gids 30000-31999 on the hos
 
 Add additional groups to run as
 
-**--healthcheck-command**=*command*
+**--healthcheck-command**=*"command"* | *'["command", "arg1", ...]'*
 
 Set or alter a healthcheck command for a container. The command is a command to be executed inside your
 container that determines your container health.  The command is required for other healthcheck options
 to be applied.  A value of `none` disables existing healthchecks.
 
+You need to specify multi option commands in the form of a json string.
+
 **--healthcheck-interval**=*interval*
 
 Set an interval for the healthchecks (a value of `disable` results in no automatic timer setup) (default "30s")