encrypter.js

function encryptText (toEncript) {

    let i, k;
    return getIv()
        .then(iv => {
            i = iv;

            return getKey()
        }).then(key => {
            k = key;

            const cipher = crypto.createCipheriv(algorithm, k, i);
            const encrypted = cipher.update(toEncript, "utf8", "hex") + cipher.final("hex");

            return encrypted;
        });
}