Programmatically Scraping Data From your Casper Suite JSS

So let’s say you’re writing a bash script and need to glean data from your JSS about a particular Mac workstation. In this case, you have the workstation name and you want to know the Mac’s IP address. Well, JAMF has provided a means to do that via the REST API.

If you contact JAMF, they’ll show you a way to obtain info about any Mac workstation in the JSS if you already know its computer ID in the JSS:

curl -v -u USERNAME:PASSWORD https://JSS.URL:8443/JSSResource/computers/id/###/subset/general -X GET | xpath //computer/general/ip_address | sed -e 's/\<ip_address>//g; s/\<\/ip_address>//g'

This is hardly useful though, as who knows each workstation’s ID? (The ID happens to be pretty much random; it’s a chronological increment based on when the Mac was enrolled in the JSS. Your 9th Mac is “9”, your 47th is “47”, etc.)

The other problem is that both ‘curl’ and ‘xpath’ are very verbose in their output. If you’re writing a command-line utility, you don’t want them mucking up the user’s screen. Luckily there’s a better way.

curl -v -u USERNAME:PASSWORD https://JSS.URL:8443/JSSResource/computers/name/NAME/subset/General | grep -Eo '<ip_address>[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}' | cut -d ">" -f2

(Note: I attempted to use ‘sed’ instead of ‘grep’ & ‘cut’ above, but ‘sed’ just wouldn’t parse the tag-laden output. Ping me if you have a solution.)

In both examples above, you of course need to substitute your authentication into USERNAME and PASSWORD, your JSS address into JSS.URL, and in the bottom example the workstation name you’re referencing into NAME.

If you try the commands directly in Terminal you’ll see the entire transaction with the server, but don’t worry; if you pipe the output to a file or use it in a full script, the output will be clean.

I’ll post more code snippets as I develop them. Specifically, I’m trying to do the reverse of the above; take an IP address and convert it into a workstation name or (better yet) serial number. Watch this space.