when not logged in, redirect to sign-in

parts of the initial setup/login stages were throwing 500s if user
not already in process (ie: user directly navigated to url):
* /resend-email-verification
* /text-not-received
* /send-new-code
* verify

app/utils.py

@@ -1,9 +1,9 @@
 import re
 import csv
-from io import BytesIO, StringIO
+from io import StringIO
 from os import path
 from functools import wraps
-from flask import (abort, session, request, url_for)
+from flask import (abort, session, request, redirect, url_for)
 import pyexcel
 import pyexcel.ext.io
 import pyexcel.ext.xls
@@ -51,6 +51,16 @@ def user_has_permissions(*permissions, admin_override=False, any_=False):
     return wrap
 
 
+def redirect_to_sign_in(f):
+    @wraps(f)
+    def wrapped(*args, **kwargs):
+        if 'user_details' not in session:
+            return redirect(url_for('main.sign_in'))
+        else:
+            return f(*args, **kwargs)
+    return wrapped
+
+
 def get_errors_for_csv(recipients, template_type):
 
     errors = []