strapi/docs/3.x.x/en/guides/upload.md

# File Upload

> ⚠️  This feature requires the Upload plugin (installed by default).

Thanks to the plugin `Upload`, you can upload any kind of files on your server or externals providers such as AWS S3.

## Usage

The plugin exposes a single route `POST /upload` to upload one or multiple files in a single request.

> ⚠️  Please send the request using multipart/form-data encoding

**Parameters**

- `files`: The file(s) to upload. The value(s) can be a Buffer or Stream.
- `refId`: (optional): The ID of the entry which the file(s) will be linked to.
- `ref`: (optional): The name of the model which the file(s) will be linked to (see more below).
- `source`: (optional): The name of the plugin where the model is located.
- `field`: (optional): The field of the entry which the file(s) will be precisely linked to.

## Models

To add a new file attribute in your models, it's like adding a new association. In the first example, you will be able to upload and attach one file to the avatar attribute. Whereas, in our second example, you can upload and attach multiple pictures to the product.

**Path —** `User.settings.json`.
```json
{
  "connection": "default",
  "attributes": {
    "pseudo": {
      "type": "string",
      "required": true
    },
    "email": {
      "type": "email",
      "required": true,
      "unique": true
    },
    "avatar": {
      "model": "file",
      "via": "related",
      "plugin": "upload"
    }
  }
}
```

**Path —** `Product.settings.json`.
```json
{
  "connection": "default",
  "attributes": {
    "name": {
      "type": "string",
      "required": true
    },
    "price": {
      "type": "integer",
      "required": true
    },
    "pictures": {
      "collection": "file",
      "via": "related",
      "plugin": "upload"
    }
  }
}
```

## Examples

**Single file**

```
curl -X POST -F 'files=@/path/to/pictures/file.jpg' http://localhost:1337/upload
```

**Multiple files**

```
curl -X POST -F 'files[]=@/path/to/pictures/fileX.jpg' -F 'files[]=@/path/to/pictures/fileY.jpg' http://localhost:1337/upload
```

**Linking files to an entry**

Let's say that you want to have a `User` model provided by the plugin `Users & Permissions` and you want to upload an avatar for a specific user.

```json
{
  "connection": "default",
  "attributes": {
    "pseudo": {
      "type": "string",
      "required": true
    },
    "email": {
      "type": "email",
      "required": true,
      "unique": true
    },
    "avatar": {
      "model": "file",
      "via": "related",
      "plugin": "upload"
    }
  }
}
```


```js
{
  "files": "...", // Buffer or stream of file(s)
  "refId": "5a993616b8e66660e8baf45c", // User's Id.
  "ref": "user", // Model name.
  "source": "users-permissions", // Plugin name.
  "field": "avatar" // Field name in the User model.
}
```

Here the request to make to associate the file (/path/to/pictures/avatar.jpg) to the user (id: 5a993616b8e66660e8baf45c) when the `User` model is provided by the `Users & Permissions` plugin.
```
curl -X POST -F 'files=@/path/to/pictures/avatar.jpg&refId=5a993616b8e66660e8baf45c&ref=user&source=users-permissions&field=avatar' http://localhost:1337/upload
```

## Install providers

By default Strapi provides a local file upload system. You might want to upload your files on AWS S3 or another provider.

To install a new provider run:

```
$ npm install strapi-upload-aws-s3@alpha --save
```

We have two providers available `strapi-upload-aws-s3` and `strapi-upload-cloudinary`, use the alpha tag to install one of them. Then, visit `/admin/plugins/upload/configurations/development` and configure the provider.

If you want to create your own, make sure the name starts with `strapi-upload-` (duplicating an existing one will be easier to create), modify the `auth` config object and customize the `upload` and `delete` functions.

Check all community providers available on npmjs.org - [Providers list](https://www.npmjs.com/search?q=strapi-upload-)