From 8df1c7119422c6920e0c162cdf3ed68c826174f5 Mon Sep 17 00:00:00 2001
From: Russ Allbery <rra@lsst.org>
Date: Fri, 22 Nov 2024 15:38:02 -0800
Subject: [PATCH] Revert "Move auth metrics reporting to a background task"

This reverts commit 2d0ea937069a8fe98371a5c19f74b030f0488c11.
The problem will be fixed in the next release of Safir in the
underlying metrics code by backgrounding the write inside the
metrics layer.
---
 changelog.d/20241122_105538_rra_DM_47716.md |  3 --
 src/gafaelfawr/handlers/ingress.py          | 53 ++++++---------------
 2 files changed, 15 insertions(+), 41 deletions(-)
 delete mode 100644 changelog.d/20241122_105538_rra_DM_47716.md

diff --git a/changelog.d/20241122_105538_rra_DM_47716.md b/changelog.d/20241122_105538_rra_DM_47716.md
deleted file mode 100644
index d5bb2d7e..00000000
--- a/changelog.d/20241122_105538_rra_DM_47716.md
+++ /dev/null
@@ -1,3 +0,0 @@
-### Bug fixes
-
-- Move metrics reporting for hot-path authentication events to a background task so that it happens in parallel with the HTTP response.
diff --git a/src/gafaelfawr/handlers/ingress.py b/src/gafaelfawr/handlers/ingress.py
index 8c25bd38..4bcf8f10 100644
--- a/src/gafaelfawr/handlers/ingress.py
+++ b/src/gafaelfawr/handlers/ingress.py
@@ -12,15 +12,8 @@
 from datetime import timedelta
 from typing import Annotated
 
-from fastapi import (
-    APIRouter,
-    BackgroundTasks,
-    Depends,
-    Header,
-    HTTPException,
-    Query,
-    Response,
-)
+import sentry_sdk
+from fastapi import APIRouter, Depends, Header, HTTPException, Query, Response
 from safir.datetime import current_datetime
 from safir.models import ErrorModel
 from safir.slack.webhook import SlackRouteErrorHandler
@@ -34,7 +27,7 @@
 from ..constants import MINIMUM_LIFETIME
 from ..dependencies.auth import AuthenticateRead
 from ..dependencies.context import RequestContext, context_dependency
-from ..events import AuthBotEvent, AuthUserEvent, FrontendEvents
+from ..events import AuthBotEvent, AuthUserEvent
 from ..exceptions import (
     ExternalUserInfoError,
     InsufficientScopeError,
@@ -312,30 +305,6 @@ async def authenticate_with_type(
     return await authenticate(context=context)
 
 
-async def publish_auth_event(
-    events: FrontendEvents, auth_config: AuthConfig, token_data: TokenData
-) -> None:
-    """Publish metrics events for a successful authentication.
-
-    Parameters
-    ----------
-    events
-        Event manager.
-    auth_config
-        Requested authentication parameters.
-    token_data
-        Successful authentication data.
-    """
-    username = token_data.username
-    service = auth_config.service
-    if is_bot_user(token_data.username):
-        bot_event = AuthBotEvent(username=username, service=service)
-        await events.auth_bot.publish(bot_event)
-    else:
-        user_event = AuthUserEvent(username=username, service=service)
-        await events.auth_user.publish(user_event)
-
-
 @router.get(
     "/ingress/auth",
     description="Meant to be used as an NGINX auth_request handler",
@@ -353,7 +322,6 @@ async def get_auth(
     token_data: Annotated[TokenData, Depends(authenticate_with_type)],
     context: Annotated[RequestContext, Depends(context_dependency)],
     response: Response,
-    background_tasks: BackgroundTasks,
 ) -> dict[str, str]:
     check_lifetime(context, auth_config, token_data)
 
@@ -392,9 +360,18 @@ async def get_auth(
     headers = await build_success_headers(context, auth_config, token_data)
     for key, value in headers:
         response.headers.append(key, value)
-    background_tasks.add_task(
-        publish_auth_event, context.events, auth_config, token_data
-    )
+
+    # Send a metric event for the authentication.
+    with sentry_sdk.start_span(name="events.publish"):
+        username = token_data.username
+        service = auth_config.service
+        if is_bot_user(username):
+            bot_event = AuthBotEvent(username=username, service=service)
+            await context.events.auth_bot.publish(bot_event)
+        else:
+            user_event = AuthUserEvent(username=username, service=service)
+            await context.events.auth_user.publish(user_event)
+
     return {"status": "ok"}