Nginx docker image for runtime configuration of Single Page Apps via environment variables.
index.html
<html>
<head>
<script type=text/javascript src="/env.js"></script>
</head>
<body>
<p id="app"></p>
<script>
document.getElementById("app").innerHTML = window._env.MSG1 + " " + window._env.MSG2;
</script>
</body>
</html>Dockerfile
FROM tamland/spa-server
ENV EXPOSE_VARS="MSG1 MSG2"
COPY index.html /var/www/html/Start
$ docker run -p 8080:80 -e MSG1=Hello -e MSG2=world helloworld:latest