NGINX Lua exporter

How to install

To install this module you have to option:

1. Use Luarocks

   luarocks install nginx-lua-exporter

2. Clone this repo or download files ( Note: We recommend using tags and releases)

How to setup

To collect data from Openresty, edit nginx.conf :

http {
...

    lua_shared_dict prometheus_memory 10M;
    lua_package_path "/< PATH TO FILES >/?.lua;;";


    log_by_lua_block {
        local collector = require("lib.collectors")
        collector.requests(ngx.var.server_name, ngx.var.status, ngx.var.server_protocol, ngx.var.request_method)
        collector.latency(ngx.var.server_name, ngx.var.request_time)
        collector.bandwith(ngx.var.server_name, ngx.var.bytes_received, ngx.var.bytes_sent)
    }
...
}

To expose metrics on /< PATH TO FILES > edit server context like this:

server {
    ...

    location /<PATH> {
        content_by_lua_block {
            local prometheus = require("nginx-lua-exporter")
            local collector = require("lib.collectors")

            collector.connection(
                                ngx.var.connections_reading,
                                ngx.var.connections_waiting,
                                ngx.var.connections_writing
                              )

            prometheus.metrics();
        }
    }
    ...
}

Test and Develop

Run a test instance with Podman or Docker:

docker run -it --rm --name nginx-lua-expoerter-test -v $PWD/example/nginx.conf:/usr/local/openresty/nginx/conf/nginx.conf  -v $PWD/example/server.conf:/etc/nginx/conf.d/default.conf -v $PWD/src:/opt/prometheus -p 8080:80 docker.io/openresty/openresty

Run lua lint test:

docker run --rm -it -v $PWD:/opt docker.io/birdy/docker-luacheck /opt --globals ngx