From 586b75749f297c84df3a004f183de49cbdc44013 Mon Sep 17 00:00:00 2001
From: pg9182 <96569817+pg9182@users.noreply.github.com>
Date: Sat, 4 Mar 2023 00:41:31 -0500
Subject: pkg/api/api0: Terminate client request handler early if request was
 canceled

This prevents unnecessary backend requests, while also reducing noise
in the metrics.
---
 pkg/api/api0/client.go | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/pkg/api/api0/client.go b/pkg/api/api0/client.go
index 45f006b..6e02603 100644
--- a/pkg/api/api0/client.go
+++ b/pkg/api/api0/client.go
@@ -143,6 +143,12 @@ func (h *Handler) handleClientOriginAuth(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
+	select {
+	case <-r.Context().Done(): // check if the request was canceled to avoid making unnecessary requests
+		return
+	default:
+	}
+
 	if !h.InsecureDevNoCheckPlayerAuth {
 		token := r.URL.Query().Get("token")
 		if token == "" {
@@ -211,8 +217,20 @@ func (h *Handler) handleClientOriginAuth(w http.ResponseWriter, r *http.Request)
 		}
 	}
 
+	select {
+	case <-r.Context().Done(): // check if the request was canceled to avoid making unnecessary requests
+		return
+	default:
+	}
+
 	username := h.lookupUsername(r, uid)
 
+	select {
+	case <-r.Context().Done(): // check if the request was canceled to avoid making unnecessary requests
+		return
+	default:
+	}
+
 	// note: there's small chance of race conditions here if there are multiple
 	// concurrent origin_auth calls, but since we only ever support one session
 	// at a time per uid, it's not a big deal which token gets saved (if it is
@@ -340,6 +358,11 @@ func (h *Handler) lookupUsername(r *http.Request, uid uint64) (username string)
 // lookupUsernameOrigin gets the username for uid from the Origin API, returning
 // an empty string if a username does not exist for the uid, and false on error.
 func (h *Handler) lookupUsernameOrigin(r *http.Request, uid uint64) (username string, ok bool) {
+	select {
+	case <-r.Context().Done(): // check if the request was canceled to avoid polluting the metrics
+		return
+	default:
+	}
 	if h.OriginAuthMgr == nil {
 		hlog.FromRequest(r).Error().
 			Str("username_source", "origin").
@@ -402,6 +425,11 @@ func (h *Handler) lookupUsernameOrigin(r *http.Request, uid uint64) (username st
 // lookupUsernameEAX gets the username for uid from the EAX API, returning an
 // empty string if a username does not exist for the uid, and false on error.
 func (h *Handler) lookupUsernameEAX(r *http.Request, uid uint64) (username string, ok bool) {
+	select {
+	case <-r.Context().Done(): // check if the request was canceled to avoid polluting the metrics
+		return
+	default:
+	}
 	if h.EAXClient == nil {
 		hlog.FromRequest(r).Error().
 			Str("username_source", "eax").
-- 
cgit v1.2.3