File size: 2,821 Bytes
681ddaf | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 | // Copyright 2018 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
const cardValidator = require('simple-card-validator');
const { v4: uuidv4 } = require('uuid');
const pino = require('pino');
const logger = pino({
name: 'paymentservice-charge',
messageKey: 'message',
formatters: {
level (logLevelString, logLevelNum) {
return { severity: logLevelString }
}
}
});
class CreditCardError extends Error {
constructor (message) {
super(message);
this.code = 400; // Invalid argument error
}
}
class InvalidCreditCard extends CreditCardError {
constructor (cardType) {
super(`Credit card info is invalid`);
}
}
class UnacceptedCreditCard extends CreditCardError {
constructor (cardType) {
super(`Sorry, we cannot process ${cardType} credit cards. Only VISA or MasterCard is accepted.`);
}
}
class ExpiredCreditCard extends CreditCardError {
constructor (number, month, year) {
super(`Your credit card (ending ${number.substr(-4)}) expired on ${month}/${year}`);
}
}
/**
* Verifies the credit card number and (pretend) charges the card.
*
* @param {*} request
* @return transaction_id - a random uuid.
*/
module.exports = function charge (request) {
const { amount, credit_card: creditCard } = request;
const cardNumber = creditCard.credit_card_number;
const cardInfo = cardValidator(cardNumber);
const {
card_type: cardType,
valid
} = cardInfo.getCardDetails();
if (!valid) { throw new InvalidCreditCard(); }
// Only VISA and mastercard is accepted, other card types (AMEX, dinersclub) will
// throw UnacceptedCreditCard error.
if (!(cardType === 'visa' || cardType === 'mastercard')) { throw new UnacceptedCreditCard(cardType); }
// Also validate expiration is > today.
const currentMonth = new Date().getMonth() + 1;
const currentYear = new Date().getFullYear();
const { credit_card_expiration_year: year, credit_card_expiration_month: month } = creditCard;
if ((currentYear * 12 + currentMonth) > (year * 12 + month)) { throw new ExpiredCreditCard(cardNumber.replace('-', ''), month, year); }
logger.info(`Transaction processed: ${cardType} ending ${cardNumber.substr(-4)} \
Amount: ${amount.currency_code}${amount.units}.${amount.nanos}`);
return { transaction_id: uuidv4() };
};
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