Allow querying and changeing i18n language via API.

i18n.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"strings"
+)
+
+// --------------------
+// internationalization
+// --------------------
+var allowedLanguages = map[string]bool{
+	"en": true,
+	"ru": true,
+	"vi": true,
+}
+
+func isLanguageAllowed(language string) bool {
+	l := strings.ToLower(language)
+	if allowedLanguages[l] {
+		return true
+	}
+	return false
+}
+
+func handleI18nCurrentLanguage(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/plain")
+	_, err := fmt.Fprintf(w, config.Language)
+	if err != nil {
+		errortext := fmt.Sprintf("Unable to write response json: %s", err)
+		log.Println(errortext)
+		http.Error(w, errortext, http.StatusInternalServerError)
+		return
+	}
+}
+
+func handleI18nChangeLanguage(w http.ResponseWriter, r *http.Request) {
+	body, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		errorText := fmt.Sprintf("failed to read request body: %s", err)
+		log.Println(errorText)
+		http.Error(w, errorText, http.StatusBadRequest)
+		return
+	}
+
+	language := strings.TrimSpace(string(body))
+	if language == "" {
+		errorText := fmt.Sprintf("empty language specified")
+		log.Println(errorText)
+		http.Error(w, errorText, http.StatusBadRequest)
+		return
+	}
+	if !isLanguageAllowed(language) {
+		errorText := fmt.Sprintf("unknown language specified: %s", language)
+		log.Println(errorText)
+		http.Error(w, errorText, http.StatusBadRequest)
+		return
+	}
+
+	httpUpdateConfigReloadDNSReturnOK(w, r)
+}