---
title: Array Processor
description: Extract, aggregate, or transform values from JSON arrays within your logs
breadcrumbs: Docs > Log Management > Log Configuration > Processors > Array Processor
---

# Array Processor

## Overview{% #overview %}

Use the array processor to extract, aggregate, or transform values from JSON arrays within your logs.

Supported operations include:

- **Select value from a matching element**
- **Compute the length of an array**
- **Append a value to an array**

Each operation is configured through a dedicated processor.

Define the array processor on the [Pipelines page](https://app.datadoghq.com/logs/pipelines).

### Select value from matching element{% #select-value-from-matching-element %}

Extract a specific value from an object inside an array when it matches a condition.

{% tab title="UI" %}

{% image
   source="https://docs.dd-static.net/images/logs/log_configuration/processor/array_processor_select_value.a3b73e7ca447d0c0dda4f0a124130ce0.png?auto=format&fit=max&w=850 1x, https://docs.dd-static.net/images/logs/log_configuration/processor/array_processor_select_value.a3b73e7ca447d0c0dda4f0a124130ce0.png?auto=format&fit=max&w=850&dpr=2 2x"
   alt="Array processor - Select value from element" /%}

**Example input:**

```json
{
  "httpRequest": {
    "headers": [
      {"name": "Referrer", "value": "https://example.com"},
      {"name": "Accept", "value": "application/json"}
    ]
  }
}
```

**Configuration steps:**

- Array path: `httpRequest.headers`
- Condition: `name:Referrer`
- Extract value of: `value`
- Target attribute: `referrer`

**Result:**

```json
{
  "httpRequest": {
    "headers": [...]
  },
  "referrer": "https://example.com"
}
```

{% /tab %}

{% tab title="API" %}
Use the [Datadog Log Pipeline API endpoint](https://docs.datadoghq.com/api/v1/logs-pipelines.md) with the following array processor JSON payload:

```json
{
  "type": "array-processor",
  "name": "Extract Referrer URL",
  "is_enabled": true,
  "operation" : {
    "type" : "select",
    "source": "httpRequest.headers",
    "target": "referrer",
    "filter": "name:Referrer",
    "value_to_extract": "value"
  }
}
```

| Parameter                    | Type    | Required | Description                                                                   |
| ---------------------------- | ------- | -------- | ----------------------------------------------------------------------------- |
| `type`                       | String  | Yes      | Type of the processor.                                                        |
| `name`                       | String  | No       | Name of the processor.                                                        |
| `is_enabled`                 | Boolean | No       | Whether the processor is enabled. Default: `false`.                           |
| `operation.type`             | String  | Yes      | Type of array processor operation.                                            |
| `operation.source`           | String  | Yes      | Path of the array you want to select from.                                    |
| `operation.target`           | String  | Yes      | Target attribute.                                                             |
| `operation.filter`           | String  | Yes      | Expression to match an array element. The first matching element is selected. |
| `operation.value_to_extract` | String  | Yes      | Attribute to read in the selected element.                                    |

{% /tab %}

### Array length{% #array-length %}

Compute the number of elements in an array.

{% tab title="UI" %}

{% image
   source="https://docs.dd-static.net/images/logs/log_configuration/processor/array_processor_length.f5538cc8be08a22cb4aba580720df7c3.png?auto=format&fit=max&w=850 1x, https://docs.dd-static.net/images/logs/log_configuration/processor/array_processor_length.f5538cc8be08a22cb4aba580720df7c3.png?auto=format&fit=max&w=850&dpr=2 2x"
   alt="Array processor - Length" /%}

**Example input:**

```json
{
  "tags": ["prod", "internal", "critical"]
}
```

**Configuration steps:**

- Array attribute: `tags`
- Target attribute: `tagCount`

**Result:**

```json
{
  "tags": ["prod", "internal", "critical"],
  "tagCount": 3
}
```

{% /tab %}

{% tab title="API" %}
Use the [Datadog Log Pipeline API endpoint](https://docs.datadoghq.com/api/v1/logs-pipelines.md) with the following array processor JSON payload:

```json
{
  "type": "array-processor",
  "name": "Compute number of tags",
  "is_enabled": true,
  "operation" : {
    "type" : "length",
    "source": "tags",
    "target": "tagCount"
  }
}
```

| Parameter          | Type    | Required | Description                                         |
| ------------------ | ------- | -------- | --------------------------------------------------- |
| `type`             | String  | Yes      | Type of the processor.                              |
| `name`             | String  | No       | Name of the processor.                              |
| `is_enabled`       | Boolean | No       | Whether the processor is enabled. Default: `false`. |
| `operation.type`   | String  | Yes      | Type of array processor operation.                  |
| `operation.source` | String  | Yes      | Path of the array to extract the length of.         |
| `operation.target` | String  | Yes      | Target attribute.                                   |

{% /tab %}

### Append to array{% #append-to-array %}

Add an attribute value to the end of a target array attribute in the log.

**Note**: If the target array attribute does not exist in the log, it is automatically created.

{% tab title="UI" %}

{% image
   source="https://docs.dd-static.net/images/logs/log_configuration/processor/array_processor_append.e11f47cf7e633a5dc975fdb206dd74ce.png?auto=format&fit=max&w=850 1x, https://docs.dd-static.net/images/logs/log_configuration/processor/array_processor_append.e11f47cf7e633a5dc975fdb206dd74ce.png?auto=format&fit=max&w=850&dpr=2 2x"
   alt="Array processor - Append" /%}

**Example input:**

```json
{
  "network": {
    "client": {
      "ip": "198.51.100.23"
    }
  },
  "sourceIps": ["203.0.113.1"]
}
```

**Configuration steps:**

- Attribute to append: `"network.client.ip"`
- Array attribute to append to: `sourceIps`

**Result:**

```json
{
  "network": {
    "client": {
      "ip": "198.51.100.23"
    }
  },
  "sourceIps": ["203.0.113.1", "198.51.100.23"]
}
```

{% /tab %}

{% tab title="API" %}
Use the [Datadog Log Pipeline API endpoint](https://docs.datadoghq.com/api/v1/logs-pipelines.md) with the following array processor JSON payload:

```json
{
  "type": "array-processor",
  "name": "Append client IP to sourceIps",
  "is_enabled": true,
  "operation" : {
    "type" : "append",
    "source": "network.client.ip",
    "target": "sourceIps"
  }
}
```

| Parameter                   | Type    | Required | Description                                                                |
| --------------------------- | ------- | -------- | -------------------------------------------------------------------------- |
| `type`                      | String  | Yes      | Type of the processor.                                                     |
| `name`                      | String  | No       | Name of the processor.                                                     |
| `is_enabled`                | Boolean | No       | Whether the processor is enabled. Default: `false`.                        |
| `operation.type`            | String  | Yes      | Type of array processor operation.                                         |
| `operation.source`          | String  | Yes      | Attribute to append.                                                       |
| `operation.target`          | String  | Yes      | Array attribute to append to.                                              |
| `operation.preserve_source` | Boolean | No       | Whether to preserve the original source after remapping. Default: `false`. |

{% /tab %}

## Further reading{% #further-reading %}

- [Discover Datadog Pipelines](https://docs.datadoghq.com/logs/log_configuration/pipelines.md)