WS – XPATH(SOAP) & JSONPATH(RESTful)

WS – XPATH(SOAP)

XPath Expressions

XPath uses a path expression to select node or list of nodes from an XML document. Following is a list of useful paths and expression to select any node/list of nodes from an XML document.

Sr.No. Expression & Description
1 node-name

Select all nodes with the given name “nodename”

2 /

Selection starts from the root node

3 //

Selection starts from the current node that match the selection

4 .

Selects the current node

5 ..

Selects the parent of the current node

6 @

Selects attributes

7 student

Example − Selects all nodes with the name “student”

8 class/student

Example − Selects all student elements that are children of class

9 //student

Selects all student elements no matter where they are in the document

Predicates

Predicates are used to find specific node or a node containing specific value and are defined using […].

Expression Result
/class/student[1] Selects the first student element that is the child of the class element.
/class/student[last()] Selects the last student element that is the child of the class element.
/class/student[last()-1] Selects the last but one student element that is the child of the class element.
//student[@rollno = ‘493’] Selects all the student elements that have an attribute named rollno with a value of ‘493’

 

WS – JSONPATH(RESTful)

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']

Operators

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

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

Filter Operators

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
subsetof left is a subset of right [?(@.sizes subsetof [‘S’, ‘M’, ‘L’])]
size size of left (array or string) should match right
empty left (array or string) should be empty

Path Examples

Given the json


 

JsonPath (click link to try) 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[-2] The second to last 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