Switching proxy settings for Maven, git, etc. (on OS X)

I am currently working for two customers at three different locations (and at home). And the proxy settings differ at every location! Sometimes I have to switch from the internal network (with proxy) to my iPhone HotSpot and then back again.

Each time I have to change my proxy settings for

• git
• Maven
• homebrew/curl/...

I tried to use a local proxy, but had some problems with Outlook (for OS X).

So I ended up creating a small shell script that checks for the proxy settings in OS X and patch Maven's settings.xml and the git configuration (as well as setting the environment variable http_proxy). It has served me well in the last weeks, so I wanted to share it.

Determining the current default network

You can have multiple active network interfaces (e.g. "Wi-Fi" and your iPhone), but one is the 'default' interface, which you can determine with:

route -n get default

this gives you the network interface, e.g. 'en0'. But for the following steps I need the network service name, i.e. "Wi-Fi", so we need to call

networksetup -listnetworkserviceorder

which produces something like:

(1) Wi-Fi
(Hardware Port: Wi-Fi, Device: en0)

(2) iPhone
(Hardware Port: iPhone USB, Device: en5)

I have to grep for the "Device" (and then get the previous line, etc.).

After all this I have the default network service name.

Determining the proxy

explicit proxy settings

If the host and port of the proxy are set explicitely, I can retrieve the sttings with

networksetup -getwebproxy "<network service name>"

The above statement prints something like:

Enabled: Yes
Server: 10.2.58.17
Port: 8080
Authenticated Proxy Enabled: 0

proxy.pac

But if I have a proxy.pac configured, I need to call

networksetup -getautoproxyurl Wi-Fi

which returns the URL for the proxy.pac file. This file is a simple JavaScript file that can be parsed with the help of pacparser

Configuring Git, Maven, etc.

Git config

When I have the PROXY_HOST and the PROXY_PORT, I can set some environment variables and tell git to use the proxy:

git config --global http.proxy "http://$PROXY_HOST:$PROXY_PRT"

Maven proxy settings

The proxy settings for Maven are located in $HOME/.m2/settings.xml. I have created a simple entry for the proxy, the id must be "env-proxy":

<proxies>
  <proxy>
    <id>env-proxy</id>
    <active>false</active>
    <protocol>http</protocol>
    <host>proxy</host>
    <port>8080</port>
  </proxy>
</proxies>

This whole block is replaced by the correct settings with the active-flag switched to true.

Un-setting

Invoking the script when no proxy can be determined removes/deactivates the proxy settings (git, Maven's settings.xml and environment variables)

Install

1. install pacparser
2. clone https://github.com/vrvolle/proxy-settings-osx.git
3. put the scripts in a directory in your PATH
4. make them executable
5. add a proxy entry "env-proxy" to your settings.xml

Invoke

To invoke the script, you must source it. Otherwise the environment variables will not be set:

source <path-to-script>/set-http-proxy