open-nomad/helper/discover/discover.go

67 lines
1.4 KiB
Go

package discover
import (
"fmt"
"os"
"os/exec"
"path/filepath"
"runtime"
"strings"
)
// NomadExecutable checks the current executable, then $GOPATH/bin, and finally
// the CWD, in that order. If it can't be found, an error is returned.
func NomadExecutable() (string, error) {
nomadExe := "nomad"
if runtime.GOOS == "windows" {
nomadExe = "nomad.exe"
}
// Check the current executable.
bin, err := os.Executable()
if err != nil {
return "", fmt.Errorf("Failed to determine the nomad executable: %v", err)
}
if _, err := os.Stat(bin); err == nil && isNomad(bin, nomadExe) {
return bin, nil
}
// Check the $PATH
if bin, err := exec.LookPath(nomadExe); err == nil {
return bin, nil
}
// Check the $GOPATH.
bin = filepath.Join(os.Getenv("GOPATH"), "bin", nomadExe)
if _, err := os.Stat(bin); err == nil {
return bin, nil
}
// Check the CWD.
pwd, err := os.Getwd()
if err != nil {
return "", fmt.Errorf("Could not find Nomad executable (%v): %v", nomadExe, err)
}
bin = filepath.Join(pwd, nomadExe)
if _, err := os.Stat(bin); err == nil {
return bin, nil
}
// Check CWD/bin
bin = filepath.Join(pwd, "bin", nomadExe)
if _, err := os.Stat(bin); err == nil {
return bin, nil
}
return "", fmt.Errorf("Could not find Nomad executable (%v)", nomadExe)
}
func isNomad(path, nomadExe string) bool {
if strings.HasSuffix(path, ".test") || strings.HasSuffix(path, ".test.exe") {
return false
}
return true
}