make endpath to lowercase in nginx using lua module

Question

I want to make request url to lowercase before setting it for proxy pass.

here is my nginx file

location ^~ /admin/(?<endpath>.*)
            {
                set_by_lua     ngx.var.endpath string.lower(ngx.var.endpath)
                proxy_pass     http://api.sample.com/api/portal/admin/$endpath$is_args$args;
            }

But I am getting error: invalid variable name "ngx.var.endpath"

Answer 1

I don't know nginx very well but from according to the docs the lua code should be a string.

So instead of

set_by_lua     ngx.var.endpath string.lower(ngx.var.endpath)

try something like

set_by_lua $endpath 'return string.lower(ngx.var.endpath)'