help request: How to setup http_upgrade on apisix dashboard

[xerox-xeon]

Description

like this:
if ($http_upgrade !~* ^WebSocket$) {
return 404;
}

Environment

• APISIX version (run apisix version):
• Operating system (run uname -a):
• OpenResty / Nginx version (run openresty -V or nginx -V):
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info):
• APISIX Dashboard version, if relevant:
• Plugin runner version, for issues related to plugin runners:
• LuaRocks version, for installation issues (run luarocks --version):

[tzssangglass]

we can use lua-resty-expr: https://github.com/api7/lua-resty-expr, it may be like:

"vars": [["http_user_upgrade", "~=", "WebSocket"]]

in APISIX Dashboard, lua-resty-expr show as 高级匹配条件