Add registration closed template and handler

core/templates/registration/registration_closed.html

@@ -0,0 +1,19 @@
+{% extends "base.html" %}
+{% load static %}
+{% load crispy_forms_tags %}
+
+{% block content %}
+  <section class="hero is-fullheight">
+    <div class="hero-body">
+      <div class="container">
+        <div class="columns is-centered">
+          <div class="column is-5-tablet is-4-desktop is-3-widescreen">
+            <div class="box">
+              <p class="has-text-danger">Registration closed.</p>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  </section>
+{% endblock %}

core/views/base.py

@@ -91,6 +91,10 @@ class Signup(CreateView):
     success_url = reverse_lazy("login")
     template_name = "registration/signup.html"
 
+    def get(self, request, *args, **kwargs):
+        if not settings.REGISTRATION_OPEN:
+            return render(request, "registration/registration_closed.html")
+        super().get(request, *args, **kwargs)
 
 class Portal(LoginRequiredMixin, View):
     async def get(self, request):