| package opts // import "github.com/docker/docker/opts" |
| |
| import ( |
| "fmt" |
| "os" |
| "runtime" |
| "strings" |
| |
| "github.com/pkg/errors" |
| ) |
| |
| // ValidateEnv validates an environment variable and returns it. |
| // If no value is specified, it returns the current value using os.Getenv. |
| // |
| // As on ParseEnvFile and related to #16585, environment variable names |
| // are not validate what so ever, it's up to application inside docker |
| // to validate them or not. |
| // |
| // The only validation here is to check if name is empty, per #25099 |
| func ValidateEnv(val string) (string, error) { |
| arr := strings.Split(val, "=") |
| if arr[0] == "" { |
| return "", errors.Errorf("invalid environment variable: %s", val) |
| } |
| if len(arr) > 1 { |
| return val, nil |
| } |
| if !doesEnvExist(val) { |
| return val, nil |
| } |
| return fmt.Sprintf("%s=%s", val, os.Getenv(val)), nil |
| } |
| |
| func doesEnvExist(name string) bool { |
| for _, entry := range os.Environ() { |
| parts := strings.SplitN(entry, "=", 2) |
| if runtime.GOOS == "windows" { |
| // Environment variable are case-insensitive on Windows. PaTh, path and PATH are equivalent. |
| if strings.EqualFold(parts[0], name) { |
| return true |
| } |
| } |
| if parts[0] == name { |
| return true |
| } |
| } |
| return false |
| } |