1 files changed, 15 insertions, 4 deletions
diff --git a/talermerchantdemos/survey/survey.py b/talermerchantdemos/survey/survey.py
index 25b97ad..562b817 100644
--- a/talermerchantdemos/survey/survey.py
+++ b/talermerchantdemos/survey/survey.py
@@ -24,17 +24,28 @@ import logging
 from urllib.parse import urljoin
 import flask
 import traceback
-from taler.util.talerconfig import TalerConfig
+from taler.util.talerconfig import TalerConfig, ConfigurationError
 from ..httpcommon import backend_get, backend_post
+import sys
+
+if not sys.version_info.major == 3 and sys.version_info.minor >= 6:
+    print("Python 3.6 or higher is required.")
+    print("You are using Python {}.{}.".format(sys.version_info.major, sys.version_info.minor))
+    sys.exit(1)
 
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
 app = flask.Flask(__name__, template_folder=BASE_DIR)
 app.debug = True
 app.secret_key = base64.b64encode(os.urandom(64)).decode('utf-8')
 TC = TalerConfig.from_env()
-BACKEND_URL = TC["frontends"]["backend"].value_string(required=True)
-CURRENCY = TC["taler"]["currency"].value_string(required=True)
-APIKEY = TC["frontends"]["backend_apikey"].value_string(required=True)
+try:
+    BACKEND_URL = TC["frontends"]["backend"].value_string(required=True)
+    CURRENCY = TC["taler"]["currency"].value_string(required=True)
+    APIKEY = TC["frontends"]["backend_apikey"].value_string(required=True)
+except ConfigurationError as ce:
+    print(ce)
+    exit(1)
+
 app.config.from_object(__name__)
 LOGGER = logging.getLogger(__name__)
 INSTANCED_URL = urljoin(BACKEND_URL, f"instances/survey/")