json-merge

The json-merge transform combines multiple upstream JSON payloads into one object. Inputs are merged in runtime order; only values that parse as JSON participate (objects by default).

When to use it

Use json-merge to assemble configuration fragments, API responses, or transform outputs from parallel branches before json-template, json-filter, or dashboard nodes.

Limitations

Does not publish dashboards or $heat-dataservice payloads.
Arrays are ignored unless allowArrays is true (shallow: last array wins; deep: replace or concat per arrayMergeMode).
Scalars are skipped unless includeNonObjectJson wraps them under scalarWrapKey.
With outputWhenNoValidJson: fail, the node fails when no input parses; default is an empty object {}.

Configuration (summary)

Property	Default	Description
`mode`	`shallow`	`shallow` or `deep` nested object merge
`allowArrays`	`false`	Allow JSON arrays as inputs
`arrayMergeMode`	`replace`	`replace` or `concat` when `allowArrays` and `mode: deep`
`includeNonObjectJson`	`false`	Wrap scalars as `{ "value": ... }`
`parseMode`	`strict`	`strict` or `lenient` (trim embedded JSON strings)
`outputWhenNoValidJson`	`emptyObject`	`emptyObject` or `fail`

Example


{
  "mode": "deep",
  "allowArrays": false
}

json-merge

When to use it

Limitations

Configuration (summary)

Example

Related