binctr/vendor/github.com/Microsoft/hcsshim/cmd/runhcs/exec.go
Jess Frazelle 94d1cfbfbf
update vendor
Signed-off-by: Jess Frazelle <acidburn@microsoft.com>
2018-09-25 12:27:46 -04:00

156 lines
3.6 KiB
Go

package main
import (
"encoding/json"
"fmt"
"os"
"path/filepath"
"syscall"
"github.com/Microsoft/hcsshim/internal/appargs"
"github.com/opencontainers/runtime-spec/specs-go"
"github.com/urfave/cli"
)
var execCommand = cli.Command{
Name: "exec",
Usage: "execute new process inside the container",
ArgsUsage: `<container-id> <command> [command options] || -p process.json <container-id>
Where "<container-id>" is the name for the instance of the container and
"<command>" is the command to be executed in the container.
"<command>" can't be empty unless a "-p" flag provided.
EXAMPLE:
For example, if the container is configured to run the linux ps command the
following will output a list of processes running in the container:
# runhcs exec <container-id> ps`,
Flags: []cli.Flag{
cli.StringFlag{
Name: "cwd",
Usage: "current working directory in the container",
},
cli.StringSliceFlag{
Name: "env, e",
Usage: "set environment variables",
},
cli.BoolFlag{
Name: "tty, t",
Usage: "allocate a pseudo-TTY",
},
cli.StringFlag{
Name: "user, u",
},
cli.StringFlag{
Name: "process, p",
Usage: "path to the process.json",
},
cli.BoolFlag{
Name: "detach,d",
Usage: "detach from the container's process",
},
cli.StringFlag{
Name: "pid-file",
Value: "",
Usage: "specify the file to write the process id to",
},
cli.StringFlag{
Name: "shim-log",
Value: "",
Usage: "path to the log file for the launched shim process",
},
},
Before: appargs.Validate(argID, appargs.Rest(appargs.String)),
Action: func(context *cli.Context) error {
id := context.Args().First()
pidFile, err := absPathOrEmpty(context.String("pid-file"))
if err != nil {
return err
}
shimLog, err := absPathOrEmpty(context.String("shim-log"))
if err != nil {
return err
}
c, err := getContainer(id, false)
if err != nil {
return err
}
status, err := c.Status()
if err != nil {
return err
}
if status != containerRunning {
return errContainerStopped
}
spec, err := getProcessSpec(context, c)
if err != nil {
return err
}
p, err := startProcessShim(id, pidFile, shimLog, spec)
if err != nil {
return err
}
if !context.Bool("detach") {
state, err := p.Wait()
if err != nil {
return err
}
os.Exit(int(state.Sys().(syscall.WaitStatus).ExitCode))
}
return nil
},
SkipArgReorder: true,
}
func getProcessSpec(context *cli.Context, c *container) (*specs.Process, error) {
if path := context.String("process"); path != "" {
f, err := os.Open(path)
if err != nil {
return nil, err
}
defer f.Close()
var p specs.Process
if err := json.NewDecoder(f).Decode(&p); err != nil {
return nil, err
}
return &p, validateProcessSpec(&p)
}
// process via cli flags
p := c.Spec.Process
if len(context.Args()) == 1 {
return nil, fmt.Errorf("process args cannot be empty")
}
p.Args = context.Args()[1:]
// override the cwd, if passed
if context.String("cwd") != "" {
p.Cwd = context.String("cwd")
}
// append the passed env variables
p.Env = append(p.Env, context.StringSlice("env")...)
// set the tty
if context.IsSet("tty") {
p.Terminal = context.Bool("tty")
}
// override the user, if passed
if context.String("user") != "" {
p.User.Username = context.String("user")
}
return p, nil
}
func validateProcessSpec(spec *specs.Process) error {
if spec.Cwd == "" {
return fmt.Errorf("Cwd property must not be empty")
}
if !filepath.IsAbs(spec.Cwd) {
return fmt.Errorf("Cwd must be an absolute path")
}
if len(spec.Args) == 0 {
return fmt.Errorf("args must not be empty")
}
return nil
}