尝试使用 apache2 设置 websocket 代理，出现以下错误：
没有协议处理程序对 URL /（方案“ws”）有效。如果您使用的是 mod_proxy 的 DSO 版本，请确保使用 LoadModule 将代理子模块包含在配置中
apache服务器的wstunnel模块已加载。以下是结果apache2ctl -M
Loaded Modules:
core_module (static)
so_module (static)
watchdog_module (static)
http_module (static)
log_config_module (static)
logio_module (static)
version_module (static)
unixd_module (static)
access_compat_module (shared)
alias_module (shared)
auth_basic_module (shared)
authn_core_module (shared)
authn_file_module (shared)
authz_core_module (shared)
authz_host_module (shared)
authz_user_module (shared)
autoindex_module (shared)
deflate_module (shared)
dir_module (shared)
env_module (shared)
filter_module (shared)
headers_module (shared)
mime_module (shared)
mpm_prefork_module (shared)
negotiation_module (shared)
php7_module (shared)
proxy_module (shared)
proxy_connect_module (shared)
proxy_fcgi_module (shared)
proxy_html_module (shared)
proxy_http_module …