ntfy/util/util.go
2022-01-06 01:04:56 +01:00

206 lines
4.5 KiB
Go

package util
import (
"errors"
"fmt"
"math/rand"
"mime"
"os"
"regexp"
"strconv"
"strings"
"sync"
"time"
)
const (
randomStringCharset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
)
var (
random = rand.New(rand.NewSource(time.Now().UnixNano()))
randomMutex = sync.Mutex{}
sizeStrRegex = regexp.MustCompile(`(?i)^(\d+)([gmkb])?$`)
errInvalidPriority = errors.New("invalid priority")
)
// FileExists checks if a file exists, and returns true if it does
func FileExists(filename string) bool {
stat, _ := os.Stat(filename)
return stat != nil
}
// InStringList returns true if needle is contained in haystack
func InStringList(haystack []string, needle string) bool {
for _, s := range haystack {
if s == needle {
return true
}
}
return false
}
// InStringListAll returns true if all needles are contained in haystack
func InStringListAll(haystack []string, needles []string) bool {
matches := 0
for _, s := range haystack {
for _, needle := range needles {
if s == needle {
matches++
}
}
}
return matches == len(needles)
}
// InIntList returns true if needle is contained in haystack
func InIntList(haystack []int, needle int) bool {
for _, s := range haystack {
if s == needle {
return true
}
}
return false
}
// SplitNoEmpty splits a string using strings.Split, but filters out empty strings
func SplitNoEmpty(s string, sep string) []string {
res := make([]string, 0)
for _, r := range strings.Split(s, sep) {
if r != "" {
res = append(res, r)
}
}
return res
}
// RandomString returns a random string with a given length
func RandomString(length int) string {
randomMutex.Lock() // Who would have thought that random.Intn() is not thread-safe?!
defer randomMutex.Unlock()
b := make([]byte, length)
for i := range b {
b[i] = randomStringCharset[random.Intn(len(randomStringCharset))]
}
return string(b)
}
// DurationToHuman converts a duration to a human readable format
func DurationToHuman(d time.Duration) (str string) {
if d == 0 {
return "0"
}
d = d.Round(time.Second)
days := d / time.Hour / 24
if days > 0 {
str += fmt.Sprintf("%dd", days)
}
d -= days * time.Hour * 24
hours := d / time.Hour
if hours > 0 {
str += fmt.Sprintf("%dh", hours)
}
d -= hours * time.Hour
minutes := d / time.Minute
if minutes > 0 {
str += fmt.Sprintf("%dm", minutes)
}
d -= minutes * time.Minute
seconds := d / time.Second
if seconds > 0 {
str += fmt.Sprintf("%ds", seconds)
}
return
}
// ParsePriority parses a priority string into its equivalent integer value
func ParsePriority(priority string) (int, error) {
switch strings.TrimSpace(strings.ToLower(priority)) {
case "":
return 0, nil
case "1", "min":
return 1, nil
case "2", "low":
return 2, nil
case "3", "default":
return 3, nil
case "4", "high":
return 4, nil
case "5", "max", "urgent":
return 5, nil
default:
return 0, errInvalidPriority
}
}
// PriorityString converts a priority number to a string
func PriorityString(priority int) (string, error) {
switch priority {
case 0:
return "default", nil
case 1:
return "min", nil
case 2:
return "low", nil
case 3:
return "default", nil
case 4:
return "high", nil
case 5:
return "max", nil
default:
return "", errInvalidPriority
}
}
// ExpandHome replaces "~" with the user's home directory
func ExpandHome(path string) string {
return os.ExpandEnv(strings.ReplaceAll(path, "~", "$HOME"))
}
// ShortTopicURL shortens the topic URL to be human-friendly, removing the http:// or https://
func ShortTopicURL(s string) string {
return strings.TrimPrefix(strings.TrimPrefix(s, "https://"), "http://")
}
// ExtensionByType is a wrapper around mime.ExtensionByType with a few sensible corrections
func ExtensionByType(contentType string) string {
switch contentType {
case "image/jpeg":
return ".jpg"
default:
exts, err := mime.ExtensionsByType(contentType)
if err == nil && len(exts) > 0 {
return exts[0]
}
return ".bin"
}
}
// ParseSize parses a size string like 2K or 2M into bytes. If no unit is found, e.g. 123, bytes is assumed.
func ParseSize(s string) (int64, error) {
matches := sizeStrRegex.FindStringSubmatch(s)
if matches == nil {
return -1, fmt.Errorf("invalid size %s", s)
}
value, err := strconv.Atoi(matches[1])
if err != nil {
return -1, fmt.Errorf("cannot convert number %s", matches[1])
}
switch strings.ToUpper(matches[2]) {
case "G":
return int64(value) * 1024 * 1024 * 1024, nil
case "M":
return int64(value) * 1024 * 1024, nil
case "K":
return int64(value) * 1024, nil
default:
return int64(value), nil
}
}