Overview

Use a JSON action to process JSON data, and convert it into specific data objects that can be used by PhixFlow for processing. The JSON Node extracts one or more records from the provided JSON object using the JSON path specified.

Properties Tab

Basic Settings

Expect literal values or expressions encapsulated within ${} syntax, for example ${in.MyValue}. A worked example of the JSON Node is provided at the end of this page.

Field	Description	Example Value
Name	Name given to the JSON Node. This will be displayed on the actionflow canvas.	MyJSONReader
Input Expression	The input expression provides the JSON data to be operated upon. Typically, this will be a simple expression pointing at an incoming attribute, such as, the body from a HTTP Node.	// Consists of the pipe name and the name of a mapped attribute `in.body`
Use Strict JSON parsing	Defines the parsing of the JSON, disabled will be lenient and enabled will be strict. Lenient parsing relaxes validation allowing the following to be present in the JSON data: Use of single quotes, for example: {'name': 'Some “quotes” in a string'} Unquoted field names, for example: {name: “value”} Unescaped control characters, including literal new lines to appear within a string. Allow trailing commas {“name”: ”value”,}	// Leaving the default option Disabled.
Path	The JSON Path expression is evaluated against the data provided by the Input Expression and returns a list of JSON elements. It determines which elements are extracted from the JSON. The path starts at the root element represented by $ and each element in the path is separated by a full stop. The ^ traverses up a node and a . traverses down the node. Note that the path determines the number of nodes that are processed, which directly correlates to the number of records returned by the JSON Node. For example, if the path returns the route element of the JSON only one record will be returned. Whereas a path that returns children nodes will return one record for each child element	// JSON Path `$.main_page.title`

Path Syntax

Expression	Description
`$`	symbol refers to the root element.
`@`	symbol refers to the current element.
`.`	is the dot-child operator, which is used to denote a child element of the current element.
`[ ]`	is used to select a child element of the current element (by name or index number).
`*`	a wildcard, returning all elements regardless of their name.
^	symbol is used to traverse up 1 element in the JSON hierarchy from child to parent.

Input Connection Points

Can Accept a single Driving input connection point.

The grid contains a list of all input connection points and their type.

To add a new input connection point, in the section toolbar click Add New to open a new input connection point and set its properties; see Input Connection Points.
To edit an existing input connection point, double-click it in the list to open its properties.
To remove an input connection point, select one and in the section toolbar click Delete.

Output Connection Points

This section has a toolbar with standard buttons. The grid contains a list of all output connection points.

To add a new output path, in the section toolbar click Add New to open a new output path and set the expression; see Output Connection Points.
To edit an existing output path, double-click it in the list to open its properties.
To remove an output path, select one and in the section toolbar click Delete.

Output Attributes

JSON is converted into data objects that can be used by PhixFlow, this information is accessed using the syntax, _result.AttributeName.

Advanced

Field	Description
Prioritise Throughput Over Ordering	When enabled, records are processed in parallel to optimise performance. This means the order records are processed is nondeterministic. When disabled (default), records are processed in the order they are provided.

Worked Example

Extracting Data

Below is an example JSON object passed to the JSON Node:

Example JSON

// Example JSON string.
{
    "main_page": {
        "page": "PF Main Page",
        "title": {
            "name": "PF Title Text",
            "data": [
                {"initials": "AA", "value" : "Alistair Andrews"},
                {"initials": "BB", "value" : "Bert Brown"}
            ]
        }
    }
}

JSON Path: $.main_page.title

This path will bring back all elements matching the JSON path including the parent/grandparents and all child elements. The path defines the starting point from which we reference the JSON nodes.

The following examples show how to reference the returned JSON data:

_result.name, returns PF Title Text
_result.^.page, returns PF Main Page
1. The ^ traverses up the JSON hierarchy.
listToString(_result.data.initials), returns "AA, BB"
1. Because there are multiple JSON nodes under _result.data.initials, an array of data is returned. See Array Handling Functions.

Note the use of

^traverses up the hierarchy 1 layer.
. is the separator between nodes
using .. traverses down the hierarchy 1 layer.

Retrieving Field Names

Example JSON

{
	"a": "1",
	"b": 2,
	"c": "xxx",
	"d": {
		"x": 1,
		"y": 2,
		"z": 3
	}
}

To retrieve the field names held in element d:

do(
	$json = jsonToItems(in.JsonIn),
	$fields = getFields($json.d),
	$fields[1]
)

Returns the first field name of d which is “x”. See getFields.

Learn More

For links to all pages in this topic, see Understanding Actionflows.