fetch_image.js

import fetch from 'axios';
import { encode, imageTypes } from './dataurl';

export const fetchRawImage = url => {
  const responseType = FileReader ? 'blob' : 'arraybuffer';

  return fetch(url, {
    method: 'GET',
    responseType,
  }).then(res => {
    const type = res.headers['content-type'];

    if (imageTypes.indexOf(type) < 0) {
      return Promise.reject(new Error(`Invalid image type: ${type}`));
    }

    return { data: res.data, type };
  });
};

export const fetchImage = url => {
  return fetchRawImage(url).then(res => encode(res.data, res.type));
};