# output

Sets the destination property that receives the rewritten JSON tree.

This parameter applies to JSON Dotted Key Rewriter (mmjsonrewrite).

Name:

  output

Scope:

  input

Type:

  string

Default:

  none

Required?:

  yes

Introduced:

  8.2410.0

## Description

Defines where the normalized JSON object is stored on the message. The property must use a JSON-capable prefix (`$!`, `$.` or `$/`). When the configuration includes a leading `$` symbol it is removed automatically before validation. Other prefixes are rejected during configuration.

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

## Output usage

    action(type="mmjsonrewrite" input="$!raw" output="$!structured")

## See also

See also the main mmjsonrewrite module documentation.

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