How to convert from blob URL to binary? - react-admin

Question

I'm using ImageInput component inside an iterator to upload images in my create form and it generates a structure like this:
"data": {
"items": [
{
"id": 1,
"title": "test",
"subTitle": "test",
"additionalAttributes": {
"price": "3452345"
},
"images": [
{
"src": {
"rawFile": {
"path": "test.jpg"
},
"src": "blob:https://localhost:44323/82c04494-244a-49eb-9d0e-6bca5a3469f7",
"title": "test.jpg"
},
"title": "d"
}
]
}
],
"contact": {
"firstName": "test",
"lastName": "test",
"jobTitle": "test",
"emailAddress": "test#test.com",
"phoneNumber": "23234"
},
"theme_id": 1,
"endDate": "2020-06-19T22:27:00.000Z",
"status": "2"
}
}
What I'm trying to do is sending the image to an API for saving in a folder. Blob URL is an internal object in the browser son it can't be used in the API, so I tried to convert the Blob URL into a binary and send to API.
Following the tutorial I can not get the expected result. Here is my code:
I created a new dataProvider like this:
export const PrivateEventProvider = {
create: (resource: string, params: any) => {
convertFileToBase64(params.data.items[0].images[0].src.src).then(
transformedPicture => {
console.log(`transformedPicture: ${transformedPicture}`);
}
);
const convertFileToBase64 = (file: { rawFile: Blob }) =>
new Promise((resolve, reject) => {
const reader = new FileReader();
reader.onload = () => resolve(reader.result);
reader.onerror = reject;
reader.readAsDataURL(file.rawFile);
});
And I have this error
Unhandled Rejection (TypeError): Failed to execute 'readAsDataURL' on
'FileReader': parameter 1 is not of type 'Blob'.
enter image description here
So my question is, which is the correct way of uploading images to a folder using react-admin?