jpq

A JSONPath command line tool to extract values from a JSON value.

Usage

jpq <xpath> <filename>

The xpath argument is a RFC 9535 JSONPath expression. The extracted result is printed on standard output.

Overview of JSONPath Syntax

This is copied from RFC 9535 JSONPath: Query Expressions for JSON

Syntax Element 	Description
$ 	root node identifier (Section 2.2)
@ 	current node identifier (Section 2.3.5) (valid only within filter selectors)
[<selectors>] 	child segment (Section 2.5.1): selects zero or more children of a node
.name 	shorthand for ['name']
.* 	shorthand for [*]
..⁠[<selectors>] 	descendant segment (Section 2.5.2): selects zero or more descendants of a node
..name 	shorthand for ..['name']
..* 	shorthand for ..[*]
'name' 	name selector (Section 2.3.1): selects a named child of an object
* 	wildcard selector (Section 2.3.2): selects all children of a node
3 	index selector (Section 2.3.3): selects an indexed child of an array (from 0)
0:100:5 	array slice selector (Section 2.3.4): start:end:step for arrays
?<logical-expr> 	filter selector (Section 2.3.5): selects particular children using a logical expression
length(@.foo) 	function extension (Section 2.4): invokes a function in a filter expression

Example

$ jq '$.store.book[*].author' test-data/rfc9535-fig1.json
[
  "Nigel Rees",
  "Evelyn Waugh",
  "Herman Melville",
  "J. R. R. Tolkien"
]