Setup a web proxy server with Docker

In this post I show you how to setup a web proxy with Docker in no time. But first of all we should ask ourselves why do we actually want to do that?

Example code: https://github.com/stefpe/squid_proxy

Why a proxy?

A proxy is sitting between a client(sending a request ) and a server(responding to the client). The proxy acts as client in front of the server

• Caching server responses
• Enforce network access policies by filtering the client requests
• Reverse proxy
• Monitoring user traffic
• Loadbalancing
• Page fragment caching via ESI (e.g. Symfony framework)
• Deploy a traffic proxy in another country/region to unblock foreign checks
• ….

As you can see a proxy offers a lot of possibilities to improve the performance and exprience of your application setup and makes your daily dev life easier.

Let’s run a proxy — Squid (old but gold)

We take it easy and use a squid proxy image ready to lift off. Squid is also easy to install on ubuntu with a simple apt install squid. So here’s the docker-compose.yml to setup the proxy:

version: "3"
services:
  proxy:
    image: datadog/squid
    ports:
      - "8080:3128"
    volumes:
      - ./squid.conf:/etc/squid/squid.conf
    restart: always

In the github project linked to this post you can find a custom squid.conf file that I already adjusted to work as simple bypass proxy server.

Tweaking the config

As you can see above in the docker-compose.yml, we can adjust the config by overwriting it via a volume mount. What got changed to be a bypass proxy?

• Disable caching and avoid autogenerating the defaul log folder:

cache_log /dev/null
cache deny all

• Disable access log(optional):

access_log none

• Allow connecting to it from everywhere (may vary for your prod setup)

http_access allow all