Friday, October 7, 2022

jq for JSON


I old enough to remember when we thought XML was going to change the programming world…then JSON saved us from that hell. Parsing and querying JSON data is fundamental task we've all coded for, but sometimes I just want to get some data locally with minimal fuss. I just learned of a really awesome library to do so: jq. Let's have a look at some cool things we can do with jq!

Start by installing jq via a utility like Homebrew:

brew install jq

With Homebrew installed and a local actors.json file, let's go to work on pulling some data!

// Using this JSON file:
// https://raw.githubusercontent.com/algolia/datasets/master/movies/actors.json

// Get the 10th item in an array
cat actors.json | jq '.[10]'
// {
//   "name": "Dwayne Johnson",
//   "rating": 1568,
//   "image_path": "/akweMz59qsSoPUJYe7QpjAc2rQp.jpg",
//   "alternative_name": "The Rock",
//   "objectID": "551486400"
// }

// Get a property from the 10th item in array
// > "Dwayne Johnson"

// Get multiple items
jq '.[10:12]'

// Get items up to the 12th position
jq '.[:12]'

// Get items after the 12th position
jq '.[12:]'

// Get an array of properties from all objects
jq '.[].name'
// > ["William Shatner", "Will Ferrell", ...]

// Create an object with only properties I want
jq '{ name: .[].name, rating: .[].rating}'

// Built in functions!
jq 'sort'
jq 'length'
jq 'reverse'

There are loads of other ways to use jq, so I highly recommend you check out JQ Select Explained: Selecting elements from JSON. I'll keep jq handy for the foreseeable future, as it will be invaluable!

  • 5 HTML5 APIs You Didn’t Know Existed

    When you say or read “HTML5”, you half expect exotic dancers and unicorns to walk into the room to the tune of “I'm Sexy and I Know It.”  Can you blame us though?  We watched the fundamental APIs stagnate for so long that a basic feature…

  • Page Visibility API

    One event that's always been lacking within the document is a signal for when the user is looking at a given tab, or another tab. When does the user switch off our site to look at something else? When do they come back?

  • Introducing MooTools ScrollSide

    This post is a proof of concept post — the functionality is yet to be perfected. Picture this: you've found yourself on a website that uses horizontal scrolling instead of vertical scrolling. It's an artistic site so you accept that the site scrolls left to right.

  • MooTools 1.2 Image Protector: dwProtector

    Image protection is a hot topic on the net these days, and why shouldn't it be? If you spent two hours designing an awesome graphic, would you want it ripped of in matter of seconds? Hell no! That's why I've created an image…


RELATED ARTICLES

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Most Popular

Recent Comments