func getDockerEnv() (*dockerEnv, error) {
dockerHost := os.Getenv("DOCKER_HOST")
var err error
if dockerHost == "" {
dockerHost, err = getDefaultDockerHost()
if err != nil {
return nil, err
}
}
dockerTLSVerify := os.Getenv("DOCKER_TLS_VERIFY") != ""
var dockerCertPath string
if dockerTLSVerify {
dockerCertPath = os.Getenv("DOCKER_CERT_PATH")
if dockerCertPath == "" {
home := homedir.Get()
if home == "" {
return nil, errors.New("environment variable HOME must be set if DOCKER_CERT_PATH is not set")
}
dockerCertPath = filepath.Join(home, ".docker")
dockerCertPath, err = filepath.Abs(dockerCertPath)
if err != nil {
return nil, err
}
}
}
return &dockerEnv{
dockerHost: dockerHost,
dockerTLSVerify: dockerTLSVerify,
dockerCertPath: dockerCertPath,
}, nil
}
// PrintDefaults prints, to standard error unless configured
// otherwise, the default values of all defined flags in the set.
func (fs *FlagSet) PrintDefaults() {
writer := tabwriter.NewWriter(fs.Out(), 20, 1, 3, ' ', 0)
home := homedir.Get()
// Don't substitute when HOME is /
if runtime.GOOS != "windows" && home == "/" {
home = ""
}
// Add a blank line between cmd description and list of options
if fs.FlagCount() > 0 {
fmt.Fprintln(writer, "")
}
fs.VisitAll(func(flag *Flag) {
format := " -%s=%s"
names := []string{}
for _, name := range flag.Names {
if name[0] != '#' {
names = append(names, name)
}
}
if len(names) > 0 && len(flag.Usage) > 0 {
val := flag.DefValue
if home != "" && strings.HasPrefix(val, home) {
val = homedir.GetShortcutString() + val[len(home):]
}
fmt.Fprintf(writer, format, strings.Join(names, ", -"), val)
for i, line := range strings.Split(flag.Usage, "\n") {
if i != 0 {
line = " " + line
}
fmt.Fprintln(writer, "\t", line)
}
}
})
writer.Flush()
}