HTTP/3: postponed session creation to init() callback. Now the session object is assigned to c->data while ngx_http_connection_t object is referenced by its http_connection field, similar to ngx_http_v2_connection_t and ngx_http_request_t. The change allows to eliminate v3_session field from ngx_http_connection_t. The field was under NGX_HTTP_V3 macro, which was a source of binary compatibility problems when nginx/module is build with/without HTTP/3 support. Postponing is essential since c->data should retain the reference to ngx_http_connection_t object throughout QUIC handshake, because SSL callbacks ngx_http_ssl_servername() and ngx_http_ssl_alpn_select() rely on this.

uwsgi_param  QUERY_STRING       $query_string;
uwsgi_param  REQUEST_METHOD     $request_method;
uwsgi_param  CONTENT_TYPE       $content_type;
uwsgi_param  CONTENT_LENGTH     $content_length;

uwsgi_param  REQUEST_URI        $request_uri;
uwsgi_param  PATH_INFO          $document_uri;
uwsgi_param  DOCUMENT_ROOT      $document_root;
uwsgi_param  SERVER_PROTOCOL    $server_protocol;
uwsgi_param  REQUEST_SCHEME     $scheme;
uwsgi_param  HTTPS              $https if_not_empty;

uwsgi_param  REMOTE_ADDR        $remote_addr;
uwsgi_param  REMOTE_PORT        $remote_port;
uwsgi_param  SERVER_PORT        $server_port;
uwsgi_param  SERVER_NAME        $server_name;