How can dynamically create upstream block with Openresty and Lua?

Question

I need to create an upstream block in the default.conf dynamically with Openresty and Lua.

upstream my_gateway{

    for server in #SERVERS_ENV:
       server xxx.xxx.xxx.xx:yyyy  max_fails=3 fail_timeout=30s;
}

Answer 1

ngx.balancer is what you are looking for.