json_path 0.5.0-dev.1 json_path: ^0.5.0-dev.1 copied to clipboard
Implementation of JSONPath expressions like "$.store.book[2].price". Reads and writes values in parsed JSON objects.
JSONPath in Dart #
import 'dart:convert';
import 'package:json_path/json_path.dart';
void main() {
final json = jsonDecode('''
{
"store": {
"book": [
{
"category": "reference",
"author": "Nigel Rees",
"title": "Sayings of the Century",
"price": 8.95
},
{
"category": "fiction",
"author": "Evelyn Waugh",
"title": "Sword of Honour",
"price": 12.99
},
{
"category": "fiction",
"author": "Herman Melville",
"title": "Moby Dick",
"isbn": "0-553-21311-3",
"price": 8.99
},
{
"category": "fiction",
"author": "J. R. R. Tolkien",
"title": "The Lord of the Rings",
"isbn": "0-395-19395-8",
"price": 22.99
}
],
"bicycle": {
"color": "red",
"price": 19.95
}
}
}
''');
final prices = JsonPath(r'$..price');
print('All prices in the store:');
/// The following code will print:
///
/// $['store']['book'][0]['price']: 8.95
/// $['store']['book'][1]['price']: 12.99
/// $['store']['book'][2]['price']: 8.99
/// $['store']['book'][3]['price']: 22.99
/// $['store']['bicycle']['price']: 19.95
prices
.read(json)
.map((node) => '${node.path}:\t${node.value}')
.forEach(print);
}
Limitations #
This library follows the in-development IETF JsonPath specification. Since the spec itself is an evolving document, the implementation may lag behind and some features may not be implemented in-full. Please refer to the tests (there are hundreds of them, including the CTS) to see what is supported.
Data manipulation #
Each Node
produced by the .read()
method contains the .pointer
property which is a valid JSON Pointer
and can be used to alter the referenced value. If you only need to manipulate JSON data,
check out my JSON Pointer implementation.