Nginx reverse proxy with basic authentication

!Nginx Basic Auth.md

Nginx Basic Auth

A simple demo of using Nginx as a reverse proxy to add basic authentication.

docker-compose.yml

services:
  application:
    image: httpd
    networks:
      - mynetwork

  nginx:
    image: nginx-basic-auth
    ports:
      - "80:80"
    depends_on:
      - application
    environment: 
      - FORWARD_HOST=application
      - FORWARD_PORT=80
      - BASIC_USERNAME=john.doe
      - BASIC_PASSWORD=myp@ssword!
    networks:
      - mynetwork

networks:
  mynetwork:

Dockerfile

FROM nginx:1.19

# Install apache2-utils to get htpasswd command
RUN apt-get update -y && apt-get install -y apache2-utils && rm -rf /var/lib/apt/lists/*

# Basic auth credentials
ENV BASIC_USERNAME=username
ENV BASIC_PASSWORD=password

# Forward host and foward port as env variables
# google.com is used as a placeholder, to be replaced using environment variables
ENV FORWARD_HOST=google.com
ENV FORWARD_PORT=80

# Nginx config file
WORKDIR /
COPY nginx-basic-auth.conf nginx-basic-auth.conf

# Startup script
COPY run.sh ./
RUN chmod 0755 ./run.sh
CMD [ "./run.sh" ]

nginx-basic-auth.conf

server {
 listen 80 default_server;

 location / {
     auth_basic             "Restricted";
     auth_basic_user_file   .htpasswd;

     proxy_pass             http://${FORWARD_HOST}:${FORWARD_PORT};
     proxy_read_timeout     900;
 }
}

run.sh

#!/bin/sh

# nginx config variable injection
envsubst < nginx-basic-auth.conf > /etc/nginx/conf.d/default.conf

# htpasswd for basic authentication
htpasswd -c -b /etc/nginx/.htpasswd $BASIC_USERNAME $BASIC_PASSWORD

nginx -g "daemon off;"