Forward viewer email funnel events and cta surface to PostHog

strix/telemetry/posthog.py

@@ -153,12 +153,29 @@ def viewer_opened(source: str, live: bool) -> None:
     )
 
 
-def viewer_cta_clicked(cta: str) -> None:
+def viewer_cta_clicked(cta: str, surface: str | None = None) -> None:
+    props = {
+        **base_props(),
+        "cta": cta[:64],
+    }
+    if surface:
+        props["surface"] = surface[:64]
+    _send("viewer_cta_clicked", props)
+
+
+_VIEWER_EMAIL_STEPS = frozenset(
+    {"email_submitted", "email_verified", "report_sent", "work_email_required"}
+)
+
+
+def viewer_email_event(step: str, purpose: str | None = None) -> None:
+    if step not in _VIEWER_EMAIL_STEPS:
+        return
     _send(
-        "viewer_cta_clicked",
+        f"viewer_{step}",
         {
             **base_props(),
-            "cta": cta[:64],
+            **({"purpose": purpose} if purpose else {}),
         },
     )
 

strix/viewer/server.py

@@ -166,15 +166,34 @@ def _make_handler(state: _ViewerState) -> type[BaseHTTPRequestHandler]:
                 return {}
             return body if isinstance(body, dict) else {}
 
+        # Funnel events the viewer is allowed to forward. This handler is the
+        # trust boundary: only these event names, with only their known props,
+        # ever reach PostHog. Everything else (including any PII) is dropped.
+        _EMAIL_EVENTS = frozenset(
+            {"email_submitted", "email_verified", "report_sent", "work_email_required"}
+        )
+
         def _handle_event(self) -> None:
             body = self._read_body()
-            # Only the viewer's own sign-up/upsell CTA click is forwarded, as an
-            # anonymous PostHog event that respects the global telemetry opt-out.
-            if body.get("event") == "cta_clicked":
-                cta = str(body.get("cta") or "unknown")
+            # Forwarded as anonymous PostHog events that respect the global
+            # telemetry opt-out. Never forward the email, code, or report body:
+            # only the whitelisted event names and their known props are passed.
+            event = body.get("event")
+            if event == "cta_clicked":
                 from strix.telemetry import posthog  # noqa: PLC0415
 
-                posthog.viewer_cta_clicked(cta)
+                cta = str(body.get("cta") or "unknown")
+                surface = body.get("surface")
+                posthog.viewer_cta_clicked(
+                    cta, surface=str(surface) if surface else None
+                )
+            elif event in self._EMAIL_EVENTS:
+                from strix.telemetry import posthog  # noqa: PLC0415
+
+                purpose = body.get("purpose")
+                posthog.viewer_email_event(
+                    str(event), purpose=str(purpose) if purpose else None
+                )
             self.send_response(HTTPStatus.NO_CONTENT)
             self.end_headers()