docs: Add endpoint for permalinks to some push notifs docs.

This will gives us the flexibility to edit our documentation, including
section names, without worrying about breaking links to docs hard-coded
in older releases / deployed self-hosted servers.

zerver/tests/test_home.py

@@ -1487,3 +1487,30 @@ class HomeTest(ZulipTestCase):
             page_params["state_data"]["realm_push_notifications_enabled_end_timestamp"],
             datetime_to_timestamp(end_timestamp),
         )
+
+
+class TestDocRedirectView(ZulipTestCase):
+    def test_doc_permalink_view(self) -> None:
+        result = self.client_get("/doc-permalinks/usage-statistics")
+        self.assertEqual(result.status_code, 302)
+        self.assertEqual(
+            result["Location"],
+            "https://zulip.readthedocs.io/en/latest/production/mobile-push-notifications.html#uploading-usage-statistics",
+        )
+
+        result = self.client_get("/doc-permalinks/basic-metadata")
+        self.assertEqual(result.status_code, 302)
+        self.assertEqual(
+            result["Location"],
+            "https://zulip.readthedocs.io/en/latest/production/mobile-push-notifications.html#uploading-basic-metadata",
+        )
+
+        result = self.client_get("/doc-permalinks/why-service")
+        self.assertEqual(result.status_code, 302)
+        self.assertEqual(
+            result["Location"],
+            "https://zulip.readthedocs.io/en/latest/production/mobile-push-notifications.html#why-a-push-notification-service-is-necessary",
+        )
+
+        result = self.client_get("/doc-permalinks/invalid-doc-id")
+        self.assertEqual(result.status_code, 404)

zerver/views/home.py

@@ -2,7 +2,7 @@ import logging
 import secrets
 
 from django.conf import settings
-from django.http import HttpRequest, HttpResponse
+from django.http import HttpRequest, HttpResponse, HttpResponseRedirect
 from django.shortcuts import redirect, render
 from django.urls import reverse
 from django.utils.cache import patch_cache_control
@@ -266,3 +266,17 @@ def home_real(request: HttpRequest) -> HttpResponse:
 @zulip_login_required
 def desktop_home(request: HttpRequest) -> HttpResponse:
     return redirect(home)
+
+
+def doc_permalinks_view(request: HttpRequest, doc_id: str) -> HttpResponse:
+    DOC_PERMALINK_MAP: dict[str, str] = {
+        "usage-statistics": "https://zulip.readthedocs.io/en/latest/production/mobile-push-notifications.html#uploading-usage-statistics",
+        "basic-metadata": "https://zulip.readthedocs.io/en/latest/production/mobile-push-notifications.html#uploading-basic-metadata",
+        "why-service": "https://zulip.readthedocs.io/en/latest/production/mobile-push-notifications.html#why-a-push-notification-service-is-necessary",
+    }
+
+    redirect_url = DOC_PERMALINK_MAP.get(doc_id)
+    if redirect_url is None:
+        return render(request, "404.html", status=404)
+
+    return HttpResponseRedirect(redirect_url)

zproject/urls.py

@@ -60,7 +60,7 @@ from zerver.views.drafts import create_drafts, delete_draft, edit_draft, fetch_d
 from zerver.views.email_mirror import email_mirror_message
 from zerver.views.events_register import events_register_backend
 from zerver.views.health import health
-from zerver.views.home import accounts_accept_terms, desktop_home, home
+from zerver.views.home import accounts_accept_terms, desktop_home, doc_permalinks_view, home
 from zerver.views.invite import (
     generate_multiuse_invite_backend,
     get_user_invites,
@@ -851,6 +851,7 @@ urls += [
     path("api/<slug:article>", api_documentation_view),
     path("policies/", policy_documentation_view),
     path("policies/<slug:article>", policy_documentation_view),
+    path("doc-permalinks/<str:doc_id>", doc_permalinks_view),
 ]
 
 urls += [