root: fix prometheus path in ServiceMonitor, return WWW-Authenticate header so basic auth is sent

helm/templates/web-sm.yaml

@@ -18,6 +18,7 @@ spec:
         name: {{ include "passbook.fullname" . }}-secret-key
         key: monitoring_username
     port: http
+    path: /metrics/
     interval: 10s
   selector:
     matchLabels:

passbook/root/monitoring.py

@@ -2,7 +2,7 @@
 from base64 import b64encode
 
 from django.conf import settings
-from django.http import Http404, HttpRequest, HttpResponse
+from django.http import HttpRequest, HttpResponse
 from django.views import View
 from django_prometheus.exports import ExportToDjangoView
 
@@ -18,6 +18,8 @@ class MetricsView(View):
         expected = b64encode(str.encode(credentials)).decode()
 
         if auth_type != "Basic" or credentials != expected:
-            raise Http404
+            response = HttpResponse(status=401)
+            response['WWW-Authenticate'] = 'Basic realm="passbook-monitoring"'
+            return response
 
         return ExportToDjangoView(request)

passbook/root/urls.py

@@ -35,7 +35,7 @@ for _passbook_app in get_apps():
 urlpatterns += [
     # Administration
     path("administration/django/", admin.site.urls),
-    path("metrics", MetricsView.as_view(), name="metrics"),
+    path("metrics/", MetricsView.as_view(), name="metrics"),
 ]
 
 if settings.DEBUG: