package pkg import ( "context" "net/http" "github.com/leonelquinteros/gotext" "golang.org/x/text/language" ) const contextLocaleKey = "numerus-locale" type Locale struct { *gotext.Locale Language language.Tag } func NewLocale(lang language.Tag) *Locale { return &Locale{ gotext.NewLocale("locales", lang.String()), lang, } } func SetLocale(db *Db, next http.Handler) http.Handler { availableLanguages := mustGetAvailableLanguages(db) var matcher = language.NewMatcher(availableLanguages) locales := map[language.Tag]*Locale{} for _, lang := range availableLanguages { locale := NewLocale(lang) locale.AddDomain("numerus") locales[lang] = locale } defaultLocale := locales[language.Catalan] return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { var locale *Locale user := getUser(r) locale = locales[user.Language] if locale == nil { t, _, err := language.ParseAcceptLanguage(r.Header.Get("Accept-Language")) if err == nil { tag, _, _ := matcher.Match(t...) var ok bool locale, ok = locales[tag] for !ok && !tag.IsRoot() { tag = tag.Parent() locale, ok = locales[tag] } } } if locale == nil { locale = defaultLocale } ctx := context.WithValue(r.Context(), contextLocaleKey, locale) next.ServeHTTP(w, r.WithContext(ctx)) }) } func getLocale(r *http.Request) *Locale { return r.Context().Value(contextLocaleKey).(*Locale) } func pgettext(context string, str string, locale *Locale) string { return locale.GetC(str, context) } func gettext(str string, locale *Locale) string { return locale.Get(str) } func mustGetAvailableLanguages(db *Db) []language.Tag { rows, err := db.Query(context.Background(), "select lang_tag from language where selectable") if err != nil { panic(err) } defer rows.Close() var langs []language.Tag for rows.Next() { var langTag string err = rows.Scan(&langTag) if err != nil { panic(err) } langs = append(langs, language.MustParse(langTag)) } if rows.Err() != nil { panic(rows.Err()) } return langs }