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Formula - JsonPathKey
The jsonPathKey Formula function returns the property names (keys), not the values, of the JSON nodes that match a JSONPath expression.
Syntax
jsonPathKey('expression', content)
Parameters
| Parameter | Required | Description |
|---|---|---|
'expression' |
Yes | A JSONPath expression in single quotes that selects the properties whose names you want, such as '$.paths.*' for every property directly under paths. |
content |
Yes | The JSON text: body, context, or the result of another function (see Formula language rules). |
Returns
The name of every property the expression selects, one value each; duplicates are collapsed. When nothing matches, nothing is returned.
To return the values of the same properties, use jsonPath with the same expression.
Examples
Example 1: List the API paths in a Swagger document
Input
The message body is a Swagger 2.0 document (shortened here):
{"swagger":"2.0","info":{"version":"V1","title":"Nodinite WebAPI","x-swagger-net-version":"8.3.38.001"},"host":"localhost","basePath":"/Nodinite/Dev/WebAPI","schemes":["http"],"paths":{"/api/activedirectorygroups":{"get":{"tags":["ActiveDirectoryGroups"],"summary":"Get a list of Active Directory Groups, limited by specified input","operationId":"ActiveDirectoryGroups_List"}}, "...": {}}}
Formula
jsonPathKey('$.paths.*', body)
Result
/api/activedirectorygroups
/api/activedirectorygroups/{id}
/api/activedirectorygroups/{id}/isnameavailable
/api/activedirectorygroups/{id}/restore
/api/activedirectorygroups/getbyfullname
...
Each key under paths is returned as its own value; the full document gives 341 unique matches.
Example 2: List the fields of an order
Input
{ "order": { "id": "PO-1001", "customer": "ACME", "total": 250 } }
Formula
jsonPathKey('$.order.*', body)
Result
id
customer
total
$.order.* selects every property directly under order; jsonPathKey returns their names, where jsonPath would return PO-1001, ACME, and 250.
Notes
jsonPathKeytakes a JSONPath expression, not a regular expression. To filter the returned names by pattern, nest the result in regex, for exampleregex('^/api/alarms', jsonPathKey('$.paths.*', body)).