Using jsonpath expression language in Dovetail
Jsonpath expression is supported by the following components:
Selecting nodes
General
JSON stands for JavaScript Object Notation. It's a lightweight data format to exchange data. JSONPath is a query language for JSON, similar to XPath for XML.
You can test your JSONPath with this Online tester.
Expression | Description |
---|---|
$ | Select from the root node. |
@ | Selects from the current node |
* | ) expresses all elements within the specified scope. For instance, book[] indicates all nodes inside a book array. |
. | Selects the child node |
[] | Selects the child node by name or index |
: | The : operator is the array slice operator, so you can slice collections using the syntax [start:end:step] to return a subcollection of a collection. |
Examples
This json is used in the examples below.
{ "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
}
}
}
Function examples
XPath | JSONPath | Result |
---|---|---|
/store/book/author | $.store.book[*].author | the authors of all books in the store |
//author | $..author | all authors |
/store/* | $.store.* | all things in store, which are some books and a red bicycle. |
/store//price | $.store..price | the price of everything in the store. |
//book[3] | $..book[2] | the third book |
//book[last()] | $..book[(@.length-1)] $..book[-1:] | the last book in order. |
//book[position()<3] | $..book[0,1] $..book[:2] | the first two books |
//book[isbn] | $..book[?(@.isbn)] | filter all books with isbn number |
//book[price<10] | $..book[?(@.price<10)] | filter all books cheapier than 10 |
//* | $..* | all Elements in XML document. All members of JSON structure. |
Useful references
For more detailed information go to: