fix exec checking for user within container

commands/exec.go

@@ -47,21 +47,23 @@ func NewKoolExec() *KoolExec {
 
 // Execute runs the exec logic with incoming arguments.
 func (e *KoolExec) Execute(args []string) (err error) {
+ if !e.IsTerminal() {
+ e.composeExec.AppendArgs("-T")
+ }
+
  if asuser := e.env.Get("KOOL_ASUSER"); asuser != "" {
  // we have a KOOL_ASUSER env; now we need to know whether
  // the image of the target service have such user
- passwd, _ := e.Exec(e.composeExec, args[0], "cat", "/etc/passwd")
- // kool:x:UID
- if strings.Contains(passwd, fmt.Sprintf("kool:x:%s", asuser)) {
- // since user existing within the container, we use it
+ var passwd string
+ if passwd, err = e.Exec(e.composeExec, args[0], "cat", "/etc/passwd"); err != nil {
+ e.Warning("failed to check running container for kool user; not setting a user (err: %s)", err.Error())
+ err = nil
+ } else if strings.Contains(passwd, fmt.Sprintf("kool:x:%s", asuser)) {
+ // since user (kool:x:UID) exists within the container, we set it
  e.composeExec.AppendArgs("--user", asuser)
  }
  }
 
- if !e.IsTerminal() {
- e.composeExec.AppendArgs("-T")
- }
-
  if aware, ok := e.composeExec.(compose.TtyAware); ok {
  // let DockerCompose know about whether we are under TTY or not
  aware.SetIsTTY(e.IsTerminal())