crypt4gh_js/src/check_fileformat.js

Crypt4GH Version JavaScript

import * as dec from './decryption.js'

/**
 * Function to check whether an already encrypted file is in crypt4gh format or not
 * and whether the person uploading the file, has access to the unencrypted data
 * @param {*} input => data to check for crypt4gh format
 * @param {*} seckey => key to decrypt input
 * @returns => false, if data can't be decrypted. true, if it can be decrypted.
 */
export async function check (input, seckey) {
  try {
    const header = await input.subarray(0, 1000)
    const headerPackets = dec.parse(header)
    if(headerPackets === undefined){
      return false
    } else{
      const decryptedPackets = await dec.decryptHeader(headerPackets[0], seckey)
      if (decryptedPackets[0].length === 0) {
        return false
      } else {
        return true
      }
    } 
  } catch (e) {
    console.trace("File checking wasn't possible!")
  }
}

export default check