Add container runlabel command

Execute the command as described by a container image.  The value of the label is processed
into a command by:

1. Ensuring the first argument of the command is podman.
2. Substituting any variables with those defined by the environment or otherwise.

If no label exists in the container image, nothing is done.

podman container runlabel LABEL IMAGE extra_args
Signed-off-by: baude <bbaude@redhat.com>

1 files changed, 57 insertions, 0 deletions

diff --git a/cmd/podman/shared/funcs.go b/cmd/podman/shared/funcs.go
new file mode 100644
index 000000000..5c401634c
--- /dev/null
+++ b/cmd/podman/shared/funcs.go
@@ -0,0 +1,57 @@
+package shared
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+// GenerateCommand takes a label (string) and converts it to an executable command
+func GenerateCommand(command, imageName, name string) []string {
+	var (
+		newCommand []string
+	)
+	if name == "" {
+		name = imageName
+	}
+	cmd := strings.Split(command, " ")
+	// Replace the first position of cmd with podman whether
+	// it is docker, /usr/bin/docker, or podman
+	newCommand = append(newCommand, "podman")
+	for _, arg := range cmd[1:] {
+		var newArg string
+		switch arg {
+		case "IMAGE":
+			newArg = imageName
+		case "IMAGE=IMAGE":
+			newArg = fmt.Sprintf("IMAGE=%s", imageName)
+		case "NAME":
+			newArg = name
+		case "NAME=NAME":
+			newArg = fmt.Sprintf("NAME=%s", name)
+		default:
+			newArg = arg
+		}
+		newCommand = append(newCommand, newArg)
+	}
+	return newCommand
+}
+
+// GenerateRunEnvironment merges the current environment variables with optional
+// environment variables provided by the user
+func GenerateRunEnvironment(name, imageName string, opts map[string]string) []string {
+	newEnv := os.Environ()
+	newEnv = append(newEnv, fmt.Sprintf("NAME=%s", name))
+	newEnv = append(newEnv, fmt.Sprintf("IMAGE=%s", imageName))
+
+	if opts["opt1"] != "" {
+		newEnv = append(newEnv, fmt.Sprintf("OPT1=%s", opts["opt1"]))
+	}
+	if opts["opt2"] != "" {
+		newEnv = append(newEnv, fmt.Sprintf("OPT2=%s", opts["opt2"]))
+	}
+	if opts["opt3"] != "" {
+		newEnv = append(newEnv, fmt.Sprintf("OPT3=%s", opts["opt3"]))
+	}
+	return newEnv
+}