# output

Sets the destination property that receives the rewritten JSON tree.

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

Name:

  output

Scope:

  input

Type:

  string

Default:

  none

Required?:

  yes

Introduced:

  8.2410.0

## Description

Defines where the transformed JSON object is stored on the message. The property must use a JSON-capable prefix (`$!`, `$.` or `$/`). When the configuration uses a leading `$` symbol, it is stripped automatically before validation. The module rejects other prefixes during configuration.

At runtime `mmjsontransform` verifies that the destination property does not already exist. Attempting to overwrite an existing value raises an error and the action aborts without modifying the message.

## Input usage

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

## See also

See also the main mmjsontransform module documentation.

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