S allius/issue385 (#386)

* ignore translation and log files

* add quart-babel

* build and install translation files

* don't export the web-ui port 8127

- for security reason the user should use the
  HA ingress and not the direkt access to the web
  dashboard

* set 'lang' in html tag

app/src/server.py

@@ -4,7 +4,9 @@ import logging.handlers
 import os
 import argparse
 from asyncio import StreamReader, StreamWriter
-from quart import Quart, Response
+from quart import Quart, Response, request
+from quart_babel import Babel
+from quart_babel.locale import get_locale
 from logging import config  # noqa F401
 from proxy import Proxy
 from inverter_ifc import InverterIfc
@@ -31,12 +33,28 @@ class ProxyState:
         ProxyState._is_up = value
 
 
+def my_get_locale():
+    # check how to get the locale form for the add-on - hass.selectedLanguage
+    # logging.info("get_locale(%s)", request.accept_languages)
+    return request.accept_languages.best_match(
+        ['de', 'en']
+    )
+
+
 app = Quart(__name__,
             template_folder='web/templates',
             static_folder='web/static')
+babel = Babel(app,
+              locale_selector=my_get_locale,
+              default_translation_directories='../translations')
 app.register_blueprint(web_routes)
 
 
+@app.context_processor
+def utility_processor():
+    return dict(lang=get_locale())
+
+
 @app.route('/-/ready')
 async def ready():
     if ProxyState.is_up():