From e75f913af3229be2ca9d26bbd26e16bb53f33f88 Mon Sep 17 00:00:00 2001
From: wiz <j@wiz.biz>
Date: Fri, 1 Nov 2024 21:20:54 +0900
Subject: [PATCH] ops: Cache testnet electrs endpoints for minimum of 1s

---
 production/nginx/location-testnet-api.conf | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/production/nginx/location-testnet-api.conf b/production/nginx/location-testnet-api.conf
index 86cc643a3..d43a51ce5 100644
--- a/production/nginx/location-testnet-api.conf
+++ b/production/nginx/location-testnet-api.conf
@@ -47,10 +47,10 @@ location /testnet/api/block/ {
 	rewrite ^/testnet/api/(.*) /$1 break;
 	try_files /dev/null @esplora-testnet-api-cache-forever;
 }
-# other API responses cannot be cached
+# we cache for 1s to mitigate DoS attacks
 location /testnet/api/ {
 	rewrite ^/testnet/api/(.*) /$1 break;
-	try_files /dev/null @esplora-testnet-api-cache-disabled;
+	try_files /dev/null @esplora-testnet-api-cache-minimal;
 }
 
 ###########
@@ -160,3 +160,20 @@ location @esplora-testnet-api-cache-forever {
 
 	expires 30d;
 }
+
+location @esplora-testnet-api-cache-minimal {
+	proxy_pass $esploraTestnet;
+
+	proxy_set_header Host $host;
+	proxy_set_header X-Real-IP $remote_addr;
+	proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+	proxy_set_header X-Forwarded-Proto $scheme;
+
+	proxy_cache_background_update off;
+	proxy_cache_use_stale error;
+	proxy_cache apihot;
+	proxy_cache_valid 200 1s;
+	proxy_redirect off;
+
+	expires 1s;
+}