Concat processor
Elastic Cloud Serverless projects are autoscaled environments, fully managed by Elastic and available on Elastic Cloud. Availability This functionality is generally available and ready for production usage. Serverless interfaces and procedures might differ from classic Elastic Stack deployments. The Elastic Stack includes Elastic's core products such as Elasticsearch, Kibana, Logstash, and Beats. Availability This functionality is generally available and ready for production usage. Unless stated otherwise on the page, this functionality is available when your Elastic Stack is deployed on Elastic Cloud Hosted, Elastic Cloud Enterprise, Elastic Cloud on Kubernetes, and self-managed environments. This documentation corresponds to the latest patch available for each minor version. If you're not using the latest patch, check the release notes for changes.
Serverless
Generally available
Stack
9.4+
Generally available since 9.4
The Concat processor concatenates a mix of field values and literal strings into a single field.
To concatenate values:
- Select Create → Create processor.
- Select Concat from the Processor menu.
- Set the items to concatenate. Each item is either a field reference or a literal string value.
- Set the Target field where the concatenated result is stored.
In YAML mode, configure the concat processor using the following parameters. For the complete Streamlang syntax, refer to the Streamlang reference.
| Parameter | Type | Required | Description |
|---|---|---|---|
from |
array | Yes | Items to concatenate. Each item is either { type: "field", value: "<field_name>" } or { type: "literal", value: "<text>" }. |
to |
string | Yes | Target field. |
ignore_missing |
boolean | No | When true, skip this processor if any referenced field is missing. |
- action: concat
from:
- type: literal
value: "User: "
- type: field
value: attributes.username
- type: literal
value: " (ID: "
- type: field
value: attributes.user_id
- type: literal
value: ")"
to: attributes.user_summary