Change OS X network location based on the Wi-Fi network name

You might have heard about Network locations in OS X. It allows you to have different network configurations and quickly switch between them. For instance, if you have to use a corporate proxy server at work and you don’t need it when you get back home, you can create a new location named “Work” (with any necessary network proxy settings) and keep the default “Automatic” location for home. But still, you would need to switch between those locations manually. How annoying!

Wouldn’t it be great if OS X could switch location automatically based on the name of Wi-Fi network that I’m connected to? Moreover, I would like to change automatically some Security Preferences, because I have to lock the computer immediately at work when I go away. But I found it annoying to have it at home.

So, how to change automatically OS X’s network location based on the name of Wi-Fi network or run arbitrary scrips when it happens? Pretty easy! We will be following a convention over configuration paradigm to reduce the overall complexity.

First of all, we have to name locations after Wi-Fi network names. For instance, if the name of your corporate wireless network is “Corp Wi-Fi”, you have to create a new location “Corp Wi-Fi”. If you connect to a wireless network that you don’t have a specific location for, then the default location “Automatic” will be used.

Then, we need to install locationchanger. It‘s a tool that watches for wireless network changes and responds accordingly. Its installation process is extremely easy:

$ curl -L https://github.com/eprev/locationchanger/raw/master/locationchanger.sh | bash

It will ask only for a root password to install locationchanger service. Now, every time you connect to a wireless network it will change the location to either the corresponding or the default one.

That’s not all. We still want to change Security Preferences automatically when the location has been changed. Let’s create scripts that will be executed every time it happens. One is for “Corp Wi-Fi” location:

#!/usr/bin/env bash

# Require password immediately after sleep or screen saver
osascript -e 'tell application "System Events" to set require password to wake of security preferences to true'

Another is for the default location:

#!/usr/bin/env bash

# Don’t require password after sleep or screen saver
osascript -e 'tell application "System Events" to set require password to wake of security preferences to false'

Save them as ~/.locations/Corp Wi-Fi and ~/.locations/Automatic respectively. Voilà! You’re not limited by changing only the security preferences, you can do whatever you want to…