From a38b01275f69b7687a221fda556dd6d06422128c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Piotr=20Poniedzia=C5=82ek?= <pondzix@gmail.com>
Date: Wed, 8 Jan 2025 09:37:02 +0100
Subject: [PATCH] More improvements in HTTP client

* Use `http.DefaultTransport`
* Set `MaxIdleConnsPerHost` equal to the `MaxIdleConns`
* Drain and close response body in defer function
---
 pkg/target/http.go | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/pkg/target/http.go b/pkg/target/http.go
index a8d4042a..7ad5c098 100644
--- a/pkg/target/http.go
+++ b/pkg/target/http.go
@@ -168,7 +168,8 @@ func newHTTPTarget(
 	if err1 != nil {
 		return nil, err1
 	}
-	transport := &http.Transport{}
+	transport := http.DefaultTransport.(*http.Transport).Clone()
+	transport.MaxIdleConnsPerHost = transport.MaxIdleConns
 
 	tlsConfig, err2 := common.CreateTLSConfiguration(certFile, keyFile, caFile, skipVerifyTLS)
 	if err2 != nil {
@@ -398,12 +399,12 @@ func (ht *HTTPTarget) Write(messages []*models.Message) (*models.TargetWriteResu
 				continue
 			}
 
-			// Ensure response body is always closed
-			if resp.StatusCode >= 200 && resp.StatusCode < 300 {
-				// Drain and close the body for successful responses
-				_, _ = io.Copy(io.Discard, resp.Body)
+			defer func() {
+				io.Copy(io.Discard, resp.Body)
 				resp.Body.Close()
+			}()
 
+			if resp.StatusCode >= 200 && resp.StatusCode < 300 {
 				for _, msg := range goodMsgs {
 					if msg.AckFunc != nil { // Ack successful messages
 						msg.AckFunc()
@@ -415,8 +416,6 @@ func (ht *HTTPTarget) Write(messages []*models.Message) (*models.TargetWriteResu
 
 			// Process non-2xx responses
 			responseBody, err := io.ReadAll(resp.Body)
-			_, _ = io.Copy(io.Discard, resp.Body)
-			resp.Body.Close() // Explicitly close the body after reading
 
 			if err != nil {
 				failed = append(failed, goodMsgs...)