git-lfs/tr/tr.go

60 lines
1.2 KiB
Go
Raw Normal View History

tr: add basic support for localization We'd like to support localizing Git LFS. We have the gotext package, which supports several different ways of getting GNU gettext-compatible locale strings. However, we need some central message catalog we can use. Let's create a singleton by the name of Tr. That means that we can translate a string by writing something like this: fmt.Println(tr.Tr.Get("This is a message about %s.", subject)) These strings can be automatically extracted by the xgotext tool available from the package github.com/leonelquinteros/gotext/cli/xgotext. While currently quite slow, it does understand Go syntax, unlike the standard GNU gettext suite. We initialize it based on the locale. Since Go does not use the standard C library, we have to emulate its behavior, as outlined in locale(7). If our locale is "en_DK.UTF-8", we first look for "en_DK" and then "en", in that order. This preserves a fallback for languages which are similar across most speakers, like English and Spanish, and can share a translation, but for locales which cannot, such pt_PT and pt_BR, or zh_TW and zh_CN, this ensures we prefer a more appropriate locale. Introduce a variable called "locales" which will be used to store Base64-encoded MO files (compiled Gettext files) for each locale. We can still load external locales from the standard directory (/usr/share/locale), but this preserves the behavior of providing a single, relocatable binary, which people like. If this becomes a problem in the future, we can revisit it. Population of this variable will come in a future commit.
2021-11-09 20:58:58 +00:00
package tr
import (
"encoding/base64"
"os"
"strings"
"github.com/leonelquinteros/gotext"
)
//go:generate go run ../tr/trgen/trgen.go
var Tr = gotext.NewLocale("/usr/share/locale", "en")
var locales = make(map[string]string)
func findLocale() string {
vars := []string{"LC_ALL", "LC_MESSAGES", "LANG"}
for _, varname := range vars {
if val, ok := os.LookupEnv(varname); ok {
return val
}
}
return ""
}
func processLocale(locale string) []string {
options := make([]string, 0, 2)
// For example, split "en_DK.UTF-8" into "en_DK" and "UTF-8".
pieces := strings.Split(locale, ".")
options = append(options, pieces[0])
// For example, split "en_DK" into "en" and "DK".
pieces = strings.Split(pieces[0], "_")
if len(pieces) > 1 {
options = append(options, pieces[0])
}
return options
}
func InitializeLocale() {
locale := findLocale()
if len(locale) == 0 {
return
}
Tr = gotext.NewLocale("/usr/share/locale", locale)
Tr.AddDomain("git-lfs")
for _, loc := range processLocale(locale) {
if moData, ok := locales[loc]; ok {
mo := gotext.NewMo()
decodedData, err := base64.StdEncoding.DecodeString(moData)
if err != nil {
continue
}
mo.Parse(decodedData)
Tr.AddTranslator("git-lfs", mo)
return
}
}
}