execute json xpath(key a, expression b, array as text c, ignore exception d)

Group

Basic Functions


Performs a JSONPath query b against an existing JSON object (under key a) in the internal cache. See function parse json and add to cache(data a, key b).

For the return value of the function, see parameter c.

Parameter Description


Parameter

Description

a

The key name of the JSON object in the cache. See function parse json and add to cache(data a, key b).

b

The JSONPath query. See https://github.com/json-path/JsonPath.

c

(optional) If true, the result of the query is returned as a JSON string. If false, the number of elements in the result JSON array or the number of key-value pairs in the result JSON object is returned. Default: false.

Alternatively, you can specify the name of a map in this parameter if the result of the query is an object. The key-value pairs of the object are then written into this map. The return value of the function will then be the number of these key-value pairs.

See examples below for illustration.

d

If true, exceptions are ignored and an empty string is returned. Default: <empty> (== false).

Examples


File:


{
"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
}


Parameter b : $.store.book[*].author

Parameter c : true

Result: ["Nigel Rees","Evelyn Waugh","Herman Melville","J. R. R. Tolkien"]

Note: The result of the query is an array with 4 elements.


Parameter b : $.store.book[*].author

Parameter c : false

Result: 4


Parameter b: $.store.book[0].['author','title']

Parameter c: true

Result: {author=Nigel Rees, title=Sayings of the Century}

Note: The result of the query is an object with 2 key-value pairs.


Parameter b: $.store.book[0].['author','title']

Parameter c: false

Result: 2


Parameter b: $.store.book[0].['author','title']

Parameter c: mymap

Result: 2

Note: The map mymap now contains the two key-value pairs author=Nigel Rees and title=Sayings of the Century.