Nothing $http_host variable of with-http_v3_module

[thinker0@…]

HTTP3+QUIC

There is no $http_host value in http_v3, so there is no value when transmitting the Host Header to upstream.

`
listen 443 quic reuseport;
listen 443 ssl backlog=65000;
http2 on;
http3 on;
.....
proxy_set_header Host $http_host;
`

upstream $http_host Host http header nothing

[Maxim Dounin]

Duplicate of #2281.

[Konstantin]

Hello.
nginx/1.26.1, the problem is still relevant.
If we use HTTP3, then the $http_host variable becomes empty.

$ nginx -V
nginx version: nginx/1.26.1
built by gcc 12.2.0 (Debian 12.2.0-14) 
built with OpenSSL 3.0.11 19 Sep 2023
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid --lock-path=/var/run/nginx.lock --http-client-body-temp-path=/var/cache/nginx/client_temp --http-proxy-temp-path=/var/cache/nginx/proxy_temp --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp --http-scgi-temp-path=/var/cache/nginx/scgi_temp --user=nginx --group=nginx --with-compat --with-file-aio --with-threads --with-http_addition_module --with-http_auth_request_module --with-http_dav_module --with-http_flv_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_mp4_module --with-http_random_index_module --with-http_realip_module --with-http_secure_link_module --with-http_slice_module --with-http_ssl_module --with-http_stub_status_module --with-http_sub_module --with-http_v2_module --with-http_v3_module --with-mail --with-mail_ssl_module --with-stream --with-stream_realip_module --with-stream_ssl_module --with-stream_ssl_preread_module --with-cc-opt='-g -O2 -ffile-prefix-map=/data/builder/debuild/nginx-1.26.1/debian/debuild-base/nginx-1.26.1=. -fstack-protector-strong -Wformat -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fPIC' --with-ld-opt='-Wl,-z,relro -Wl,-z,now -Wl,--as-needed -pie'

$ uname -a
Linux sitedd 6.1.0-21-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.90-1 (2024-05-03) x86_64 GNU/Linux