[React] Add S3 signed url image upload example

[pabloferro]

Summary

Add S3 signed url image upload example

Useful info

Creating an apisauce instance and uploading blob to S3

signedURL should come from an api call to the API.

import { create } from 'apisauce';
const uploadApi = create({ baseURL: '' });

const uploadFile = ({ signedURL, name, data, type, }) =>
    const headers = {
      'Content-Type': type
    };
    return uploadApi.put(signedURL, data, { headers }).then(uploadResponse => {
      if (!uploadResponse.ok) {
        throw Error('errors.fileUpload');
      }
      return response.data.url.split('?')[0];
    });
  });

Uploading from file

const uploadFromFile = (file, resource) =>
  uploadFile({ name: file.rawFile.name, data: file.rawFile, type: file.rawFile.type, resource });

Uploading from base64

const uploadImageFromBase64 = (src, resource, index) => {
  const blob = dataURItoBlob(src);
  return uploadFile({
    name: `content_image_${index}.${blob.type.split('/')[1]}`,
    data: blob,
    type: blob.type,
    resource
  });
};