> ## Documentation Index
> Fetch the complete documentation index at: https://docs.activeviam.com/llms.txt
> Use this file to discover all available pages before exploring further.

# CSV loading topic

> Configuration reference for `CsvTopicDescription` properties such as `file-pattern`, `parser`, `channels`, and source restrictions, plus implicit CSV loading topics enabled by default.

### Configuration properties

Properties for a CSV Loading Topic are defined by name in the `dlc.csv.topics` namespace,
and are picked up as configurations for the DLC.

| Key                   | Required | Type                  | Default                                                                | Description                                                                                                         |
| --------------------- | :------: | --------------------- | :--------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| file-pattern          |          | `String`              |                                                                        | Path matcher.                                                                                                       |
| parser                |          | `CsvParserProperties` | Default Parser.                                                        | [CSV Parser](/configuration/csv/csv-parser)                                                                         |
| channels              |          | `Set<Channel>`        | A channel is created using the topic's name as the name of the target. | [Channels](/configuration/channel).                                                                                 |
| restrict-to-sources   |          | `Set<String>`         |                                                                        | Sources *to* which the topic is restricted. See [source to topic matching](/functional/source-to-topic-matching).   |
| restrict-from-sources |          | `Set<String>`         |                                                                        | Sources *from* which the topic is restricted. See [source to topic matching](/functional/source-to-topic-matching). |

#### YAML example

This configuration does not specify a target for the data or the data format.

<Note>
  If the topic is not named the same as the store, the target must be explicitly specified in the [channel](/configuration/channel) of the topic.
</Note>

* The target is implicitly the Atoti table named "Trades".
* The format (column order and how input fields are parsed) implicitly comes from the columns and types of the targeted Atoti table, in this case "Trades".

```yaml theme={"languages":{"custom":["/engine/python-sdk/0.9/languages/pycon.tmLanguage.json"]}}
dlc:
  csv:
    topics:
      Trades:
        file-pattern: glob:trades*.csv
```

#### JSON example

CSV Topics can also be provided as an override in a DLC `LOAD` request.

```json theme={"languages":{"custom":["/engine/python-sdk/0.9/languages/pycon.tmLanguage.json"]}}
{
  "Trades": {
    "filePattern": "glob:different_than_trades*.csv"
  }
}
```

### Java configuration

`CsvTopicDescription` Spring Beans are picked up as configurations for the DLC.

| Parameter           | Required | Type                      | Default                                                               | Description                                                                                                         |
| ------------------- | :------: | ------------------------- | :-------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| name                |     Y    | `String`                  |                                                                       | Name of the topic.                                                                                                  |
| filePattern         |          | `String`                  |                                                                       | Path matcher.                                                                                                       |
| parser              |          | `CsvParserDescription`    | Default Parser.                                                       | [CSV Parser](/configuration/csv/csv-parser).                                                                        |
| channels            |          | `Set<ChannelDescription>` | A channel is created using the topic's name as the name of the target | [Channel Descriptions](/configuration/channel) which belong to the topic.                                           |
| restrictToSources   |          | `Set<String>`             |                                                                       | Sources *to* which the topic is restricted. See [source to topic matching](/functional/source-to-topic-matching).   |
| restrictFromSources |          | `Set<String>`             |                                                                       | Sources *from* which the topic is restricted. See [source to topic matching](/functional/source-to-topic-matching). |

#### Java example

This configuration does not specify a target for the data or the data format.

<Note>
  If the topic is not named the same as the store, the target must be explicitly specified in the [channel](/configuration/channel) of the topic.
</Note>

* The target is implicitly the Atoti table named "Trades".
* The format (column order and how input fields are parsed) implicitly comes from the columns and types of the targeted Atoti table, in this case "Trades".

```java theme={"languages":{"custom":["/engine/python-sdk/0.9/languages/pycon.tmLanguage.json"]}}
@Bean
public CsvTopicDescription tradesTopic() {
    return CsvTopicDescription.builder("Trades", "glob:trades*.csv")
            .build();
}
```

#### Implicit CSV loading topics

Implicit CSV loading topics allow specific files to be loaded into a datastore table without configuring a topic.

By default, implicit topics are enabled. They can be disabled by setting the `dlc.csv.implicit-load-topics-enabled` property to `false`.

When using implicit CSV loading topics:

* The topic name **must** match the name of an existing datastore table.
* The files to load must be specified via the `files` scope key.

##### Example

```json theme={"languages":{"custom":["/engine/python-sdk/0.9/languages/pycon.tmLanguage.json"]}}
{
  "operation": "LOAD",
  "topics": ["TradeTable"],
  "scope": {
    "files": ["path/to/file1.csv", "path/to/file2.csv"]
  }
}
```