Uno Yakshi UnoYakshi

There are many ways to parse in variable into the nginx config file. Some uses set_by_lua which is offered by lua-nginx-module. Some use envstubst to populate varilabes into a template file.

Today I am going to show you how to do that with njs the JS scripting engine for nginx.

## /etc/nginx/fetch_env.js
function fetch_upstream_host(r) {
 return process.env.UPSTREAM_HOST;

	<!-- should be in templates/ -->
	<html>
	<head>
	<style>
	div.mermaid {
	width:25%;
	}
	</style>
	</head>
	<body>