# stdout

The `filter_stdout` filter plugin prints events to the standard output (or logs if launched as a daemon). This filter plugin is useful for debugging purposes.

It is included in the Fluentd's core.

## Example Configurations

```
<filter pattern>
  @type stdout
</filter>
```

A sample output is as follows:

```
2017-11-28 11:43:13.814351757 +0900 tag: {"field1":"value1","field2":"value2"}
```

where the first part shows the output **time**, the second part shows the **tag**, and the third part shows the **record**.

## Plugin Helpers

* [`formatter`](https://docs.fluentd.org/plugin-helper-overview/api-plugin-helper-formatter)
* [`compat_parameters`](https://docs.fluentd.org/plugin-helper-overview/api-plugin-helper-compat_parameters)
* [`inject`](https://docs.fluentd.org/plugin-helper-overview/api-plugin-helper-inject)

## Parameters

See [Common Parameters](https://docs.fluentd.org/configuration/plugin-common-parameters).

### `@type` (required)

The value must be `stdout`.

### `<format>` Section

See [Format section configurations](https://docs.fluentd.org/configuration/format-section) for more details.

#### `@type`

| type   | default | version |
| ------ | ------- | ------- |
| string | stdout  | 0.14.5  |

The format of the output.

#### `output_type`

| type   | default | version |
| ------ | ------- | ------- |
| string | json    | 0.14.5  |

This is the option of `stdout` format. Configures the format of the record (third part). Any formatter plugins can be specified.

### `<inject>` Section

See [Inject Section Configurations](https://docs.fluentd.org/configuration/inject-section) for more details.

## Learn More

* [Filter Plugin Overview](https://docs.fluentd.org/filter)

If this article is incorrect or outdated, or omits critical information, please [let us know](https://github.com/fluent/fluentd-docs-gitbook/issues?state=open). [Fluentd](http://www.fluentd.org/) is an open-source project under [Cloud Native Computing Foundation (CNCF)](https://cncf.io/). All components are available under the Apache 2 License.