kpod exec

Initial wiring of kpod exec. We wont support the following options
for exec:

* detach -- unsure of use case
* detach-keys -- not supported by runc
* interactive -- all terminals will be interactive

Not adding exec tests as we need to think about how to support a
test that requires console access but our CI tests have no console.

Signed-off-by: baude <bbaude@redhat.com>

2 files changed, 87 insertions, 0 deletions

diff --git a/cmd/kpod/exec.go b/cmd/kpod/exec.go
new file mode 100644
index 000000000..f76983810
--- /dev/null
+++ b/cmd/kpod/exec.go
@@ -0,0 +1,86 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/pkg/errors"
+	"github.com/projectatomic/libpod/libpod"
+	"github.com/urfave/cli"
+)
+
+var (
+	execFlags = []cli.Flag{
+		cli.StringSliceFlag{
+			Name:  "env, e",
+			Usage: "Set environment variables",
+		},
+		cli.BoolFlag{
+			Name:  "privileged",
+			Usage: "Give the process extended Linux capabilities inside the container.  The default is false",
+		},
+		cli.BoolFlag{
+			Name:  "tty, t",
+			Usage: "Allocate a pseudo-TTY. The default is false",
+		},
+		cli.StringFlag{
+			Name:  "user, u",
+			Usage: "Sets the username or UID used and optionally the groupname or GID for the specified command",
+		},
+	}
+	execDescription = `
+	kpod exec
+
+	Run a command in a running container
+`
+
+	execCommand = cli.Command{
+		Name:        "exec",
+		Usage:       "Run a process in a running container",
+		Description: execDescription,
+		Flags:       execFlags,
+		Action:      execCmd,
+		ArgsUsage:   "CONTAINER-NAME",
+	}
+)
+
+func execCmd(c *cli.Context) error {
+	var envs []string
+	args := c.Args()
+	if len(args) < 1 {
+		return errors.Errorf("you must provide one container name or id")
+	}
+	if len(args) < 2 {
+		return errors.Errorf("you must provide a command to exec")
+	}
+	cmd := args[1:]
+	runtime, err := getRuntime(c)
+	if err != nil {
+		return errors.Wrapf(err, "error creating libpod runtime")
+	}
+	defer runtime.Shutdown(false)
+
+	ctr, err := runtime.LookupContainer(args[0])
+	if err != nil {
+		return errors.Wrapf(err, "unable to exec into %s", args[0])
+	}
+	// Create a list of keys provided by the user
+	var userEnvKeys []string
+	for _, env := range c.StringSlice("env") {
+		splitEnv := strings.Split(env, "=")
+		userEnvKeys = append(userEnvKeys, splitEnv[0])
+	}
+
+	envs = append(envs, c.StringSlice("env")...)
+
+	// if the default key isnt in the user-provided list, add the default
+	// key and value to the environment variables.  this is needed to set
+	// PATH for example.
+	for k, v := range defaultEnvVariables {
+		if !libpod.StringInSlice(k, userEnvKeys) {
+			envs = append(envs, fmt.Sprintf("%s=%s", k, v))
+		}
+	}
+
+	return ctr.Exec(c.Bool("tty"), c.Bool("privileged"), envs, cmd, c.String("user"))
+}
diff --git a/cmd/kpod/main.go b/cmd/kpod/main.go
index 7382644b9..708031dc9 100644
--- a/cmd/kpod/main.go
+++ b/cmd/kpod/main.go
@@ -37,6 +37,7 @@ func main() {
 		attachCommand,
 		createCommand,
 		diffCommand,
+		execCommand,
 		exportCommand,
 		historyCommand,
 		imagesCommand,