# input

Names the JSON property that provides the object to transform.

This parameter applies to JSON Dotted Key Transformer (mmjsontransform).

Name:

  input

Scope:

  input

Type:

  string

Default:

  none

Required?:

  yes

Introduced:

  8.2410.0

## Description

Specifies which message property contains the JSON object that will be rewritten. The value must be a property reference that begins with `$` (for example `$!raw` or `$.normalized`). `mmjsontransform` validates the expression during configuration and rejects other prefixes.

If the referenced property is missing at runtime, the action simply returns without altering the message. When the property exists but is not a JSON object, the module reports an error and the action fails, leaving the output property untouched.

## Input usage

    action(type="mmjsontransform" input="$!raw" output="$!normalized")

## See also

See also the main mmjsontransform module documentation.

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