@enface/js/src/utils.js

Biometric researches

const isNodeEnvironment = (
  typeof process === 'object'
  && typeof process.versions === 'object'
  && typeof process.versions.node !== 'undefined'
);

const readFileAsArrayBuffer = async file => {
  return new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.onload = (event => {
      resolve(event.target.result);
    });
    reader.onerror = (error => {
      reject(error);
    });
    reader.readAsArrayBuffer(file);
  });
};

export const nameImagesByIndex = images => {
  return images.map((item, index) => {
    item.name = `${index}.jpg`;
    return item;
  });
};

export const isUuid = string => {
  const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
  return uuidRegex.test(string);
};

export const checkImages = async (images, minLength, minSize) => {
  if (
    !images
    || !Array.isArray(images)
    || minLength !== images.length
  ) {
    throw new Error(`images array of length ${minLength} required`);
  }
  return Promise.all(images.map(async (item, index) => {
    if (item instanceof Uint8Array) item = item.buffer;
    if (
      !(item instanceof ArrayBuffer)
    ) {
      if (!isNodeEnvironment && item instanceof File) {
        item = await readFileAsArrayBuffer(item);
      } else throw new Error(`image [${index}] is not an instance of ArrayBuffer`);
    }
    if (item.byteLength < minSize) throw new Error(`image [${index}] is too small`);
    return item;
  }));
};

export const isObject = obj => {
  return obj === Object(obj);
};

export const filterObject = (obj, filteredKey) => {
  for (const key of Object.keys(obj)) {
    delete obj[filteredKey];
    if (isObject(obj[key])) {
      obj[key] = filterObject(obj[key], filteredKey);
    }
  }
  return obj;
};