Intro

Problem statement

Introducing jq

jq "Hello, world!"

Extracting single field from JSON document

Filtering JSON objects by a single field

Transforming output to contain only specific fields

Returning raw values

Conclusion

Intro

jq intro

jq object identifier index

Arrays

Arrays constructors

Object constructors

Sorting and counting

About Earthly

Maps and selects

Review

Intro

What we are going to learn?

Calling openlibrary.org Search API with curl

Using object/value iterator

Transforming input JSON to the desired format

Filtering null values with the select function

Sorting an array by the specific field using sort_by(expr)

Limiting the number of elements using limit(n;expr)

Grouping elements by the specific field using group_by(expr)

End screen

Welcome and introduction

Using the BTP Setup Automator container image for easy access to all the tools incl. jq, ijq and more

Taking a look at some of the jq command line options (via jq --help)

Starting with jqterm for our session

Considering valid JSON values

Thinking about streams of JSON values

Looking what slurp (-s) does for us

Considering raw input (-R) for non-JSON values

Looking briefly at the jq language server

Exploring some more realistic JSON, obtained via the btp CLI

Understanding what data the filter is looking

Shorthand vs longhand filter expression

Capturing data via the variable operator, and how data is (or isn't) consumed

Using 'map', passing a filter expression, and how it's similar to JS

Asking for the length of an object gives us the number of properties

Understanding how jq passed data to multiple consuming filters

Producing objects using convenient property shorthand features

Filtering data out with 'select' plus a predicate expression

Sorting with 'sort_by'

Producing a flat list of values for further consumption or file storage, with raw output (-r)

A brief digression to consider the importance of the array iterator (.[]) and how it produces multiple values downstream

Looking at what the @tsv and @csv formatters will do for us

Transforming structure with 'group_by' and taking care to understand the new structure produced

Another digression on 'first' being just syntactic sugar for .[0]

A brief intro to how 'add' can add objects together

Welcome

Jq Versions

Extracting values from objects

Making lists

Assignment Operator

Length built-in function

String formatting

Making decisions about limits

The else clause

Adding an auth token

Nested data in JSON

Jq essentials

Array slicing

Transforming data into a Key-Value pair

Demo

Using a Docker container for JQ

Dictionary creation

Counting elements in a dataset

Getting the names of tracks on the first album

Conclusion

Introduction

Array and Object Indexing

Constructors

Pipes and Functions

Sample JSON Curl

The Three Levels

Another Example with Pipes

Write your own function

Agenda

Comma filter

Hash Keys

Alternative operator

Regex Flags

Comma functionality

Querying an object

Regular Expressions

Using flags

Conclusion

Why I care about jq

Why I made a video about jq

What is jq

Using kubectl to get information about my Kubernetes Pods

Make the json output pretty with jq

Filter Expressions are where the magic of jq happen

Start to work with Arrays and Functions in jq

Using pipes in jq

Finding all the possible functions in jq

Working with indexes in jq

Get the environment variables from one pod using jq

Get the env vars for all the pods using jq

Add up the numbers in jq

Dealing with repeated fields using jq

Getting multiple values out of json with jq

Making new objects using jq

Using Map Select in jq to find specific values in jq

What else is in Adam’s article about jq

I hope you think jq is as cool as I think it is

Intro

Basics of JSON

Install jq

Read json data with jq

Create a json file

Get content of json file

Read two or more object values from a json file

Increase values in json file using jq

Read two values starting from a particular index

Conclusion

Intro

JSON Example

Inspecting JSON

Jq Data Types

Jq Expressions

Functions