From adfe966c465e46acf77d387231ace671fe302aa3 Mon Sep 17 00:00:00 2001
From: Pavel Kovalenko <jokserfn@yandex-team.ru>
Date: Wed, 11 Nov 2020 12:30:32 +0300
Subject: [PATCH] Support HTTP proxy and HTTPS S3 endpoint configuration.

---
 src/IO/S3/PocoHTTPClient.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/IO/S3/PocoHTTPClient.cpp b/src/IO/S3/PocoHTTPClient.cpp
index 49ccb6dc1b3..00cc5f497dc 100644
--- a/src/IO/S3/PocoHTTPClient.cpp
+++ b/src/IO/S3/PocoHTTPClient.cpp
@@ -168,12 +168,16 @@ void PocoHTTPClient::makeRequestInternal(
 
             auto request_configuration = per_request_configuration(request);
             if (!request_configuration.proxyHost.empty())
+            {
+                /// Turn on tunnel mode if proxy scheme is HTTP while endpoint scheme is HTTPS.
+                bool use_tunnel = request_configuration.proxyScheme == Aws::Http::Scheme::HTTP && poco_uri.getScheme() == "https";
                 session->setProxy(
                     request_configuration.proxyHost,
                     request_configuration.proxyPort,
                     Aws::Http::SchemeMapper::ToString(request_configuration.proxyScheme),
-                    false /// Disable proxy tunneling by default
+                    use_tunnel
                 );
+            }
 
             Poco::Net::HTTPRequest poco_request(Poco::Net::HTTPRequest::HTTP_1_1);