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Formula - isnull
New 6.1
The isnull function, one of the Logical functions in the Formula plugin for Search Field Expressions, returns a default value when the content is null or empty, and the content itself otherwise.
Syntax
isnull(content, 'default')
Parameters
| Parameter | Required | Description |
|---|---|---|
content |
✅ Yes | The value to check, typically the result of another Formula function such as jsonPath or xPath, or body or context. |
'default' |
✅ Yes | The text to return when content is null or empty, in single quotes. |
Returns
- The
'default'text whencontentis null or empty. - Otherwise the value of
content, unchanged.
Quoting, nesting, and how content is resolved are described in the Formula language rules.
Examples
Example 1: Return the default when the value is null
Input
Message Body:
{ "name": null }
Formula
isnull(jsonPath('name', body), 'default')
Result
default
The name property is null, so isnull returns the default text.
jsonPath finds no value for the null property, so the fallback text is used.
Example 2: Return the value when it is present
Input
Message Body:
{ "name": "John Doe" }
Formula
isnull(jsonPath('name', body), 'default')
Result
John Doe
The name property has a value, so isnull returns it unchanged.
Same formula as Example 1; with a value present, the default text is not used.