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": "ipsum" }

... into something like this:

{
    "foo": "lorem",
    "bar": "ipsum"
}

Answer 1

You can use: jq

It's very simple to use and it works great! It can handle very large JSON structures, including streams. You can find their tutorials here.

Here is an example:

$ jq . <<< '{ "foo": "lorem", "bar": "ipsum" }'
{
  "bar": "ipsum",
  "foo": "lorem"
}

Or in other words:

$ echo '{ "foo": "lorem", "bar": "ipsum" }' | jq .
{
  "bar": "ipsum",
  "foo": "lorem"
}

Answer 2

It is not too simple with a native way with the jq tools.

For example:

cat xxx | jq .

Answer 3

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 4

I recommend using the json_xs command line utility which is included in the JSON::XS perl module. JSON::XS is a Perl module for serializing/deserializing JSON, on a Debian or Ubuntu machine you can install it like this:

sudo apt-get install libjson-xs-perl

It is obviously also available on CPAN.

To use it to format JSON obtained from a URL you can use curl or wget like this:

$ curl -s http://page.that.serves.json.com/json/ | json_xs

or this:

$ wget -q -O - http://page.that.serves.json.com/json/ | json_xs

and to format JSON contained in a file you can do this:

$ json_xs < file-full-of.json

To reformat as YAML, which some people consider to be more humanly-readable than JSON:

$ json_xs -t yaml < file-full-of.json

Answer 5

With Perl, use the CPAN module JSON::XS. It installs a command line tool json_xs.

Validate:

json_xs -t null < myfile.json

Prettify the JSON file src.json to pretty.json:

< src.json json_xs > pretty.json

If you don't have json_xs, try json_pp . "pp" is for "pure perl" – the tool is implemented in Perl only, without a binding to an external C library (which is what XS stands for, Perl's "Extension System").

Answer 6

Install yajl-tools with the command below:

sudo apt-get install yajl-tools

then,

echo '{"foo": "lorem", "bar": "ipsum"}' | json_reformat