MovieNight/common/utils.go

62 lines
1.5 KiB
Go

package common
// Misc utils
import (
"net/http"
"os"
"path/filepath"
"regexp"
)
var usernameRegex *regexp.Regexp = regexp.MustCompile(`^[0-9a-zA-Z_-]*[a-zA-Z0-9]+[0-9a-zA-Z_-]*$`)
const InvalidNameError string = `Invalid name.<br />Name must be between 3 and 36 characters in length; contain only numbers, letters, underscores or dashes; and contain at least one number or letter.<br />Names cannot contain spaces.`
// IsValidName checks that name is within the correct ranges, follows the regex defined
// and is not a valid color name
func IsValidName(name string) bool {
return 3 <= len(name) && len(name) <= 36 &&
usernameRegex.MatchString(name)
}
// Return the absolut directory containing the MovieNight binary
func RunPath() string {
ex, er := os.Executable()
if er != nil {
panic(er)
}
return filepath.Dir(ex)
}
func Substr(input string, start int, length int) string {
asRunes := []rune(input)
if start >= len(asRunes) {
return ""
}
if start+length > len(asRunes) {
length = len(asRunes) - start
}
return string(asRunes[start : start+length])
}
// Return the value of "Forwarded" or "X-Forwarded-For",
// if "Forwarded" & "X-Forwarded-For" are present then "Forwarded" value is returned.
// Return "" if "Forwarded" and "X-Forwarded-For" are absent.
func ExtractForwarded(r *http.Request) string {
f := r.Header.Get("Forwarded")
if f != "" {
return f
}
xff := r.Header.Get("X-Forwarded-For")
if xff != "" {
return xff
}
return ""
}