how can i parse the output of `defaults read` on OS X?

Question

how can i parse the output of the OS X defaults read terminal command?

it appears to output the 'old' NeXTSTEP plist format; things that look like:

{
"Apple Global Domain" =     {
    AppleAntiAliasingThreshold = 4;
    AppleCollationOrder = root;

i tried writing the output to a file and converting with plutil, but it chokes:

> defaults read > defaults.txt
> plutil -convert xml1 defaults.txt
2014-02-02 21:29:14.856 plutil[56896:707] CFPropertyListCreateFromXMLData(): Old-style
plist parser: missing semicolon in dictionary on line 10835. Parsing will be abandoned.
Break on _CFPropertyListMissingSemicolon to debug.
defaults.txt: Property List error: Unexpected character { at line 1 / JSON error: No
value for key in object around character 28.

why, you ask?

i'd like to store the defaults values in git so i can keep a record as a change setting and diff after applying changes, but it seems the serialization in defaults read is not 'line order stable': dictionaries do not dump their keys in consistent order, causing a huge amount of noise. if i can parse defaults read, i can then pipe the data out through an order-consistent serializer.

Answer 1

You’re a lucky guy, just few days ago someone released a parser of the NeXTSTEP plist format on PyPi – nsplist.

Answer 2

plutil can convert to xml or json

#!/bin/bash
f='~/Library/Preferences/com.apple.LaunchServices/com.apple.launchservices.secure'
x="$(plutil -convert xml1 -o - "$f")"
j="$(plutil -convert json -o - "$f")"

-o - means: print result to stdout
$f is the input file in plist format