> For the complete documentation index, see [llms.txt](https://docs.highsidelabs.co/feed-transformer/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.highsidelabs.co/feed-transformer/feed-types/tab.md).

# Flat file feeds

### Supported feed types

The feed transformer library has support for these deprecated flat file feed types:

* `POST_FLAT_FILE_INVLOADER_DATA`
* `POST_FLAT_FILE_PRICEANDQUANTITYONLY_UPDATE_DATA`
* `POST_FLAT_FILE_LISTINGS_DATA`

We're working on support for these feed types:

* `POST_FLAT_FILE_CONVERGENCE_LISTINGS_DATA`
* `POST_FLAT_FILE_BOOKLOADER_DATA`
* `POST_UIEE_BOOKLOADER_DATA`

If you need support for one of the feed types that is still in development, [let us know](mailto:hi@highsidelabs.co) and we'll prioritize it.<br>

### Common required parameters&#x20;

All flat file feed types require an extra `merchantId` parameter to be passed to the converter methods. You can find your region-specific Amazon merchant ID [here](https://sellercentral.amazon.com/sw/AccountInfo/MerchantToken/step/MerchantToken).

{% hint style="info" %}
(If you primarily sell outside the US and that merchant ID link doesn't work for you, try copying it and replacing `sellercentral.amazon.com` with the Seller Central URL that you usually use.)
{% endhint %}

Here's how to pass the merchant id:

```php
use SellingPartnerApi\FeedTransformer\Transformer;
use SellingPartnerApi\FeedTransformer\FeedTypes\Invloader;

$feedFile = 'path/to/your/feed.tab';
$json = Transformer::fromFile(
    Invloader::$feedType,  // -> POST_FLAT_FILE_INVLOADER_DATA
    $feedFile,
    'ATVPDKIKX0DER',
    ['merchantId' => 'A2DI..........']
);

$jsonFeedPath = 'path/to/new/feed.json';
file_put_contents($jsonFeedPath, json_encode($json));
```

Check the documentation pages for the specific feed type(s) you're working with to see if you need to pass other feed-type-specific parameters.