From 966fa9957d5a57fa5633ba9c8d6eef091fb545c1 Mon Sep 17 00:00:00 2001
From: a10zn8 <a1.cyb3r@gmail.com>
Date: Tue, 18 Jul 2023 15:33:07 +0400
Subject: [PATCH] add gzip to prom endpoint

---
 .../io/emeraldpay/dshackle/monitoring/MonitoringSetup.kt  | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/main/kotlin/io/emeraldpay/dshackle/monitoring/MonitoringSetup.kt b/src/main/kotlin/io/emeraldpay/dshackle/monitoring/MonitoringSetup.kt
index b407d687..374513f7 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/monitoring/MonitoringSetup.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/monitoring/MonitoringSetup.kt
@@ -33,6 +33,7 @@ import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.stereotype.Service
 import java.io.IOException
 import java.net.InetSocketAddress
+import java.util.zip.GZIPOutputStream
 import javax.annotation.PostConstruct
 
 @Service
@@ -83,9 +84,12 @@ class MonitoringSetup(
                 )
                 server.createContext(monitoringConfig.prometheus.path) { httpExchange ->
                     val response = prometheusRegistry.scrape()
-                    httpExchange.sendResponseHeaders(200, response.toByteArray().size.toLong())
+                    httpExchange.responseHeaders.add("Content-Encoding", "gzip")
+                    httpExchange.sendResponseHeaders(200, 0)
                     httpExchange.responseBody.use { os ->
-                        os.write(response.toByteArray())
+                        GZIPOutputStream(os).use { gzos ->
+                            gzos.write(response.toByteArray())
+                        }
                     }
                 }
                 Thread(server::start).start()