Display meaningful error messages in manual domain entry, and give user an option to retry

letsencrypt/display/ops.py

@@ -250,7 +250,41 @@ def _choose_names_manually():
         "Please enter in your domain name(s) (comma and/or space separated) ")
 
     if code == display_util.OK:
-        return display_util.separate_list_input(input_)
+        invalid_domains = dict()
+        retry_message = ""
+        try:
+            domain_list = display_util.separate_list_input(input_)
+        except UnicodeEncodeError:
+            domain_list = []
+            retry_message = (
+                "Internationalized domain names are not presently "
+                "supported.{0}{0}Would you like to re-enter the "
+                "names?{0}").format(os.linesep)
+
+        for domain in domain_list:
+            try:
+                le_util.check_domain_sanity(domain)
+            except errors.ConfigurationError as e:
+                invalid_domains[domain] = e.message
+
+        if len(invalid_domains):
+            retry_message = (
+                "One or more of the entered domain names was not valid:"
+                "{0}{0}").format(os.linesep)
+            for domain in invalid_domains:
+                retry_message = retry_message + "{1}: {2}{0}".format(
+                    os.linesep, domain, invalid_domains[domain])
+            retry_message = retry_message + (
+                "{0}Would you like to re-enter the names?{0}").format(
+                    os.linesep)
+
+        if retry_message:
+            # We had error in input
+            retry = util(interfaces.IDisplay).yesno(retry_message)
+            if retry:
+                return _choose_names_manually()
+        else:
+            return domain_list
     return []