How can I pretty-print JSON in a shell script?

Question

Is there a (Unix) shell script to format JSON in human-readable form?

Basically, I want it to transform the following:

{ \"foo\": \"lorem\", \"bar\":         


        

Answer 1

Thanks to J.F. Sebastian's very helpful pointers, here's a slightly enhanced script I've come up with:

#!/usr/bin/python

"""
Convert JSON data to human-readable form.

Usage:
  prettyJSON.py inputFile [outputFile]
"""

import sys
import simplejson as json


def main(args):
    try:
        if args[1] == '-':
            inputFile = sys.stdin
        else:
            inputFile = open(args[1])
        input = json.load(inputFile)
        inputFile.close()
    except IndexError:
        usage()
        return False
    if len(args) < 3:
        print json.dumps(input, sort_keys = False, indent = 4)
    else:
        outputFile = open(args[2], "w")
        json.dump(input, outputFile, sort_keys = False, indent = 4)
        outputFile.close()
    return True


def usage():
    print __doc__


if __name__ == "__main__":
    sys.exit(not main(sys.argv))

Answer 2

1. brew install jq
2. command + | jq
3. (example: curl localhost:5000/blocks | jq)
4. Enjoy!

Answer 3

I wrote a tool that has one of the best "smart whitespace" formatters available. It produces more readable and less verbose output than most of the other options here.

underscore-cli

This is what "smart whitespace" looks like:

I may be a bit biased, but it's an awesome tool for printing and manipulating JSON data from the command-line. It's super-friendly to use and has extensive command-line help/documentation. It's a Swiss Army knife that I use for 1001 different small tasks that would be surprisingly annoying to do any other way.

Latest use-case: Chrome, Dev console, Network tab, export all as HAR file, "cat site.har | underscore select '.url' --outfmt text | grep mydomain"; now I have a chronologically ordered list of all URL fetches made during the loading of my company's site.

Pretty printing is easy:

underscore -i data.json print

Same thing:

cat data.json | underscore print

Same thing, more explicit:

cat data.json | underscore print --outfmt pretty

This tool is my current passion project, so if you have any feature requests, there is a good chance I'll address them.

Answer 4

I use jshon to do exactly what you're describing. Just run:

echo $COMPACTED_JSON_TEXT | jshon

You can also pass arguments to transform the JSON data.

Answer 5

With Perl, if you install JSON::PP from CPAN you'll get the json_pp command. Stealing the example from B Bycroft you get:

[pdurbin@beamish ~]$ echo '{"foo": "lorem", "bar": "ipsum"}' | json_pp
{
   "bar" : "ipsum",
   "foo" : "lorem"
}

It's worth mentioning that json_pp comes pre-installed with Ubuntu 12.04 (at least) and Debian in /usr/bin/json_pp

Answer 6

The JSON Ruby Gem is bundled with a shell script to prettify JSON:

sudo gem install json
echo '{ "foo": "bar" }' | prettify_json.rb

Script download: gist.github.com/3738968