Prometheus node exporter

Package like prometheus-node-exporter-lua-ltq-dsl it's not available for install giving me package not found though I can see it on github https://github.com/openwrt/packages/blob/openwrt-19.07/utils/prometheus-node-exporter-lua/files/usr/lib/lua/prometheus-collectors/ltq-dsl.lua

Like so many other Prometheus collectors which are available on

bmx6.lua
bmx7.lua
conntrack.lua
cpu.lua
filefd.lua
loadavg.lua
ltq-dsl.lua
meminfo.lua
nat_traffic.lua
netdev.lua
netstat.lua
openwrt.lua
textfile.lua
time.lua
uname.lua
wifi.lua
wifi_stations.lua 

Only few of them available as install-able packages

prometheus-node-exporter-lua-bmx6_2019.11.17-1_all.ipk	1.4 KB	Sun Aug 16 07:30:41 2020
prometheus-node-exporter-lua-bmx7_2019.11.17-1_all.ipk	1.6 KB	Sun Aug 16 07:30:41 2020
prometheus-node-exporter-lua-nat_traffic_2019.11.17-1_all.ipk	1.4 KB	Sun Aug 16 07:30:38 2020
prometheus-node-exporter-lua-netstat_2019.11.17-1_all.ipk	1.3 KB	Sun Aug 16 07:30:39 2020
prometheus-node-exporter-lua-openwrt_2019.11.17-1_all.ipk	1.2 KB	Sun Aug 16 07:30:42 2020
prometheus-node-exporter-lua-textfile_2019.11.17-1_all.ipk	1.1 KB	Sun Aug 16 07:30:42 2020
prometheus-node-exporter-lua-wifi_2019.11.17-1_all.ipk	1.4 KB	Sun Aug 16 07:30:40 2020
prometheus-node-exporter-lua-wifi_stations_2019.11.17-1_all.ipk	1.6 KB	Sun Aug 16 07:30:40 2020
prometheus-node-exporter-lua_2019.11.17-1_all.ipk	4.3 KB	Sun Aug 16 07:30:38 2020

Any idea why? and what can be done about it?

Asked @gui about it, and he says:

Based on https://github.com/openwrt/packages/blob/openwrt-19.07/utils/prometheus-node-exporter-lua/Makefile#L88 it depends on @(PACKAGE_ltq-adsl-app||PACKAGE_ltq-vdsl-app) and none of the two packages is available in https://downloads.openwrt.org/releases/19.07.3/ , something might be failing in the compilation of those packages so it is not compiling theprometheus-node-exporter-lua-ltq-dsl.

I hope this is useful.

I am not sure about that.
According to this post

It's been used in @dhewg setup, I asked him already but his is not very active and haven't replied.
That's why I created this topic.