JsonPath expressions always refer to a JSON structure in the same way as XPath expression are used in combination
with an XML document. The “root member object” in JsonPath is always referred to as $ regardless if it is an
object or array.
JsonPath expressions can use the dot–notation
$.store.book[0].title
or the bracket–notation
$['store']['book'][0]['title']
| Operator | Description |
|---|---|
$ |
The root element to query. This starts all path expressions. |
@ |
The current node being processed by a filter predicate. |
* |
Wildcard. Available anywhere a name or numeric are required. |
.. |
Deep scan. Available anywhere a name is required. |
.<name> |
Dot-notated child |
['<name>' (, '<name>')] |
Bracket-notated child or children |
[<number> (, <number>)] |
Array index or indexes |
[start:end] |
Array slice operator |
[?(<expression>)] |
Filter expression. Expression must evaluate to a boolean value. |
Functions can be invoked at the tail end of a path - the input to a function is the output of the path expression. The function output is dictated by the function itself.
| Function | Description | Output |
|---|---|---|
| min() | Provides the min value of an array of numbers | Double |
| max() | Provides the max value of an array of numbers | Double |
| avg() | Provides the average value of an array of numbers | Double |
| stddev() | Provides the standard deviation value of an array of numbers | Double |
| length() | Provides the length of an array | Integer |
Filters are logical expressions used to filter arrays. A typical filter would be [?(@.age > 18)] where @ represents the current item being processed. More complex filters can be created with logical operators && and ||. String literals must be enclosed by single or double quotes ([?(@.color == 'blue')] or [?(@.color == "blue")]).
| Operator | Description |
|---|---|
| == | left is equal to right (note that 1 is not equal to ‘1’) |
| != | left is not equal to right |
| < | left is less than right |
| <= | left is less or equal to right |
| > | left is greater than right |
| >= | left is greater than or equal to right |
| =~ | left matches regular expression [?(@.name =~ /foo.*?/i)] |
| in | left exists in right [?(@.size in [‘S’, ‘M’])] |
| nin | left does not exists in right |
| size | size of left (array or string) should match right |
| empty | left (array or string) should be empty |
Given the json
{
"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
}
},
"expensive": 10
}
| JsonPath | Result |
|---|---|
$.store.book[*].author |
The authors of all books |
$..author |
All authors |
$.store.* |
All things, both books and bicycles |
$.store..price |
The price of everything |
$..book[2] |
The third book |
$..book[0,1] |
The first two books |
$..book[:2] |
All books from index 0 (inclusive) until index 2 (exclusive) |
$..book[1:2] |
All books from index 1 (inclusive) until index 2 (exclusive) |
$..book[-2:] |
Last two books |
$..book[2:] |
Book number two from tail |
$..book[?(@.isbn)] |
All books with an ISBN number |
$.store.book[?(@.price < 10)] |
All books in store cheaper than 10 |
$..book[?(@.price <= $['expensive'])] |
All books in store that are not “expensive” |
$..book[?(@.author =~ /.*REES/i)] |
All books matching regex (ignore case) |
$..* |
Give me every thing |
$..book.length() |
The number of books |