Extracting i18n functionality to i18n core library (#16914)

* extracting i18n functionality to i18n core library * Removing utils.T * Adding documentation and changing one function name for better explanation * Changing other missing utils.T * Adding license string * Renaming corelibs to pkg * Renaming corelibs to pkg (moving directory) * Renaming from pkg to shared * Fixing bodyPage.Html casing * Fixing merges * Fixing merge problem * Fixing tests
2021-02-26 08:12:49 +01:00
--- a/shared/i18n/i18n.go
+++ b/shared/i18n/i18n.go
@@ -0,0 +1,185 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package i18n
+
+import (
+	"fmt"
+	"html/template"
+	"io/ioutil"
+	"net/http"
+	"path/filepath"
+	"reflect"
+	"strings"
+
+	"github.com/mattermost/go-i18n/i18n"
+
+	"github.com/mattermost/mattermost-server/v5/mlog"
+)
+
+const defaultLocale = "en"
+
+// TranslateFunc is the type of the translate functions
+type TranslateFunc func(translationID string, args ...interface{}) string
+
+// T is the translate function using the default server language as fallback language
+var T TranslateFunc
+
+// TDefault is the translate function using english as fallback language
+var TDefault TranslateFunc
+
+var locales map[string]string = make(map[string]string)
+var defaultServerLocale string
+var defaultClientLocale string
+
+// TranslationsPreInit loads translations from filesystem if they are not
+// loaded already and assigns english while loading server config
+func TranslationsPreInit(translationsDir string) error {
+	if T != nil {
+		return nil
+	}
+
+	// Set T even if we fail to load the translations. Lots of shutdown handling code will
+	// segfault trying to handle the error, and the untranslated IDs are strictly better.
+	T = tfuncWithFallback(defaultLocale)
+	TDefault = tfuncWithFallback(defaultLocale)
+
+	return initTranslationsWithDir(translationsDir)
+}
+
+// InitTranslations set the defaults configured in the server and initialize
+// the T function using the server default as fallback language
+func InitTranslations(serverLocale, clientLocale string) error {
+	defaultServerLocale = serverLocale
+	defaultClientLocale = clientLocale
+
+	var err error
+	T, err = getTranslationsBySystemLocale()
+	return err
+}
+
+func initTranslationsWithDir(dir string) error {
+	files, _ := ioutil.ReadDir(dir)
+	for _, f := range files {
+		if filepath.Ext(f.Name()) == ".json" {
+			filename := f.Name()
+			locales[strings.Split(filename, ".")[0]] = filepath.Join(dir, filename)
+
+			if err := i18n.LoadTranslationFile(filepath.Join(dir, filename)); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func getTranslationsBySystemLocale() (TranslateFunc, error) {
+	locale := defaultServerLocale
+	if _, ok := locales[locale]; !ok {
+		mlog.Warn("Failed to load system translations for", mlog.String("locale", locale), mlog.String("attempting to fall back to default locale", defaultLocale))
+		locale = defaultLocale
+	}
+
+	if locales[locale] == "" {
+		return nil, fmt.Errorf("failed to load system translations for '%v'", defaultLocale)
+	}
+
+	translations := tfuncWithFallback(locale)
+	if translations == nil {
+		return nil, fmt.Errorf("failed to load system translations")
+	}
+
+	mlog.Info("Loaded system translations", mlog.String("for locale", locale), mlog.String("from locale", locales[locale]))
+	return translations, nil
+}
+
+// GetUserTranslations get the translation function for an specific locale
+func GetUserTranslations(locale string) TranslateFunc {
+	if _, ok := locales[locale]; !ok {
+		locale = defaultLocale
+	}
+
+	translations := tfuncWithFallback(locale)
+	return translations
+}
+
+// GetTranslationsAndLocaleFromRequest return the translation function and the
+// locale based on a request headers
+func GetTranslationsAndLocaleFromRequest(r *http.Request) (TranslateFunc, string) {
+	// This is for checking against locales like pt_BR or zn_CN
+	headerLocaleFull := strings.Split(r.Header.Get("Accept-Language"), ",")[0]
+	// This is for checking against locales like en, es
+	headerLocale := strings.Split(strings.Split(r.Header.Get("Accept-Language"), ",")[0], "-")[0]
+	defaultLocale := defaultClientLocale
+	if locales[headerLocaleFull] != "" {
+		translations := tfuncWithFallback(headerLocaleFull)
+		return translations, headerLocaleFull
+	} else if locales[headerLocale] != "" {
+		translations := tfuncWithFallback(headerLocale)
+		return translations, headerLocale
+	} else if locales[defaultLocale] != "" {
+		translations := tfuncWithFallback(defaultLocale)
+		return translations, headerLocale
+	}
+
+	translations := tfuncWithFallback(defaultLocale)
+	return translations, defaultLocale
+}
+
+// GetSupportedLocales return a map of locale code and the file path with the
+// translations
+func GetSupportedLocales() map[string]string {
+	return locales
+}
+
+func tfuncWithFallback(pref string) TranslateFunc {
+	t, _ := i18n.Tfunc(pref)
+	return func(translationID string, args ...interface{}) string {
+		if translated := t(translationID, args...); translated != translationID {
+			return translated
+		}
+
+		t, _ := i18n.Tfunc(defaultLocale)
+		return t(translationID, args...)
+	}
+}
+
+// TranslateAsHTML translates the translationID provided and return a
+// template.HTML object
+func TranslateAsHTML(t TranslateFunc, translationID string, args map[string]interface{}) template.HTML {
+	message := t(translationID, escapeForHTML(args))
+	message = strings.Replace(message, "[[", "<strong>", -1)
+	message = strings.Replace(message, "]]", "</strong>", -1)
+	return template.HTML(message)
+}
+
+func escapeForHTML(arg interface{}) interface{} {
+	switch typedArg := arg.(type) {
+	case string:
+		return template.HTMLEscapeString(typedArg)
+	case *string:
+		return template.HTMLEscapeString(*typedArg)
+	case map[string]interface{}:
+		safeArg := make(map[string]interface{}, len(typedArg))
+		for key, value := range typedArg {
+			safeArg[key] = escapeForHTML(value)
+		}
+		return safeArg
+	default:
+		mlog.Warn(
+			"Unable to escape value for HTML template",
+			mlog.Any("html_template", arg),
+			mlog.String("template_type", reflect.ValueOf(arg).Type().String()),
+		)
+		return ""
+	}
+}
+
+// IdentityTfunc returns a translation function that don't translate, only
+// returns the same id
+func IdentityTfunc() TranslateFunc {
+	return func(translationID string, args ...interface{}) string {
+		return translationID
+	}
+}
--- a/shared/i18n/i18n_test.go
+++ b/shared/i18n/i18n_test.go
@@ -0,0 +1,69 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package i18n
+
+import (
+	"testing"
+
+	"github.com/mattermost/go-i18n/i18n/bundle"
+	"github.com/mattermost/go-i18n/i18n/language"
+	"github.com/mattermost/go-i18n/i18n/translation"
+	"github.com/stretchr/testify/assert"
+)
+
+var htmlTestTranslationBundle *bundle.Bundle
+
+func init() {
+	htmlTestTranslationBundle = bundle.New()
+	fooBold, _ := translation.NewTranslation(map[string]interface{}{
+		"id":          "foo.bold",
+		"translation": "<p>[[{{ .Foo }}]]</p>",
+	})
+	htmlTestTranslationBundle.AddTranslation(&language.Language{Tag: "en"}, fooBold)
+}
+
+func TestTranslateAsHTML(t *testing.T) {
+	assert.EqualValues(t, "<p><strong>&lt;i&gt;foo&lt;/i&gt;</strong></p>", TranslateAsHTML(TranslateFunc(htmlTestTranslationBundle.MustTfunc("en")), "foo.bold", map[string]interface{}{
+		"Foo": "<i>foo</i>",
+	}))
+}
+
+func TestEscapeForHTML(t *testing.T) {
+	stringForPointer := "<b>abc</b>"
+	for name, tc := range map[string]struct {
+		In       interface{}
+		Expected interface{}
+	}{
+		"NoHTML": {
+			In:       "abc",
+			Expected: "abc",
+		},
+		"String": {
+			In:       "<b>abc</b>",
+			Expected: "&lt;b&gt;abc&lt;/b&gt;",
+		},
+		"StringPointer": {
+			In:       &stringForPointer,
+			Expected: "&lt;b&gt;abc&lt;/b&gt;",
+		},
+		"Map": {
+			In: map[string]interface{}{
+				"abc": "abc",
+				"123": "<b>123</b>",
+			},
+			Expected: map[string]interface{}{
+				"abc": "abc",
+				"123": "&lt;b&gt;123&lt;/b&gt;",
+			},
+		},
+		"Unsupported": {
+			In:       struct{ string }{"<b>abc</b>"},
+			Expected: "",
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			assert.Equal(t, tc.Expected, escapeForHTML(tc.In))
+		})
+	}
+}