feat: pwa notifications

tracker/push_api.py

@@ -0,0 +1,79 @@
+from django.conf import settings
+from django.http import HttpRequest
+from ninja import Router, Schema
+from ninja.errors import HttpError
+
+from accounts.auth import AUTH
+from accounts.models import PushSubscription
+from tracker.push import notify_user, push_is_configured
+
+router = Router(auth=AUTH)
+
+
+class SubscriptionKeys(Schema):
+    p256dh: str
+    auth: str
+
+
+class SubscribeIn(Schema):
+    """Exactly the shape of a browser PushSubscription, so the client can post it as-is."""
+
+    endpoint: str
+    keys: SubscriptionKeys
+
+
+class UnsubscribeIn(Schema):
+    endpoint: str
+
+
+@router.post("/subscribe")
+def subscribe(request: HttpRequest, payload: SubscribeIn):
+    """Register this device for reminders. Re-subscribing the same endpoint is a no-op."""
+    if not push_is_configured():
+        raise HttpError(503, "Push is not configured on the server.")
+
+    PushSubscription.objects.update_or_create(
+        endpoint=payload.endpoint,
+        defaults={
+            "user": request.user,
+            "p256dh": payload.keys.p256dh,
+            "auth": payload.keys.auth,
+            "user_agent": request.headers.get("User-Agent", "")[:300],
+        },
+    )
+    return {"detail": "Reminders enabled on this device."}
+
+
+@router.post("/unsubscribe")
+def unsubscribe(request: HttpRequest, payload: UnsubscribeIn):
+    PushSubscription.objects.filter(
+        user=request.user, endpoint=payload.endpoint
+    ).delete()
+    return {"detail": "Reminders disabled on this device."}
+
+
+@router.post("/test")
+def send_test(request: HttpRequest):
+    """Push a notification right now, to prove the chain works end to end."""
+    if not request.user.push_subscriptions.exists():
+        raise HttpError(400, "No device has enabled reminders yet.")
+
+    delivered = notify_user(
+        request.user,
+        {
+            "title": "Osiris — test",
+            "body": "Reminders are working. This is what a dose reminder looks like.",
+            "url": "/admin/today/",
+            "tag": "test",
+        },
+    )
+    if not delivered:
+        raise HttpError(502, "The push service rejected the message.")
+
+    return {"detail": f"Sent to {delivered} device(s)."}
+
+
+@router.get("/public-key", auth=None)
+def public_key(request: HttpRequest):
+    """The applicationServerKey the browser needs in order to subscribe."""
+    return {"public_key": settings.VAPID_PUBLIC_KEY}