{
    "upload_url": "https://upload-url.invalid",
    "upload_params": {
        "AWSAccessKeyId": "ABC123",
        "Filename": "",
        "key": "key",
        "acl": "private",
        "Policy": "policy",
        "Signature": "signature",
        "success_action_redirect": "https://my_redirect.invalid/redirect?my_param=100",
        "content-type": "image/jpg"
    },
    "file_param": "file"
}