jq

jq

Jq (JSON Query) is a lightweight and powerful command-line JSON processor used to parse, filter, and transform JSON data. It’s a must-have tool for any Linux user who works with JSON data.

What can jq do?

• Parse and validate JSON data
• Filter and select specific fields or values from JSON data
• Transform and modify JSON data using various functions (e.g., convert dates, change data types)
• Join or split JSON arrays and objects
• Perform arithmetic operations on numeric values

Use cases for jq

• Working with API responses that return JSON data
• Parsing and validating configuration files in JSON format
• Transforming data from one format to another (e.g., CSV to JSON)
• Automating tasks using JSON data as input or output

Special hacks for jq

• Use -c option to pretty-print JSON: jq -c <json_file> will print the JSON data in a human-readable, compact format.
• Use –arg and –argjson options to pass variables: You can use these options to pass variables to jq expressions. For example: echo '{"name": "$NAME", "age": $AGE}' | jq --arg NAME="John" --arg AGE=30
• Use the .[] syntax to iterate over arrays: This allows you to process each element in an array independently.

Experience level required

jq is a powerful tool that can be used at various levels of Linux expertise. However, it’s likely most useful for:

• Intermediate users who work with JSON data on a regular basis
• Developers who need to parse and transform API responses or configuration files
• Power users who want to automate tasks using JSON data as input or output

If you’re new to Linux, jq might seem daunting at first. However, it’s definitely worth learning, especially if you plan to work with JSON data frequently.