Add support for GPC header (#219)

* chore: reflect both headers in debugging

* chore: add Sec-GPC handling with DNT handling

The `if` statement is there purely so that nothing more has to change handling wise. If either value is true, DNT policy should kick in and no data should be stored/tracked. *Should* just work™.

* fix: meet Black style guide

* fix: comply with other header formatting

* fix: header typo

shynet/analytics/tasks.py

@@ -61,7 +61,7 @@ def ingress_request(
         log.debug(f"Linked to service {service}")
 
         if dnt and service.respect_dnt:
-            log.debug("Ignoring because of DNT")
+            log.debug("Ignoring because of DNT or GPC")
             return
 
         try:

shynet/analytics/views/ingress.py

@@ -29,6 +29,9 @@ def ingress(request, service_uuid, identifier, tracker, payload):
     location = request.META.get("HTTP_REFERER", "").strip()
     user_agent = request.META.get("HTTP_USER_AGENT", "").strip()
     dnt = request.META.get("HTTP_DNT", "0").strip() == "1"
+    gpc = request.META.get("HTTP_SEC_GPC", "0").strip() == "1"
+    if gpc or dnt:
+        dnt = True
 
     ingress_request.delay(
         service_uuid,