Coupon Service

REST API service for discount coupons/vouchers, built in Node.js.

Inspired by the Stripe API, but sometimes you need coupons without credit cards. Also supports discounts based on (partial) email addresses, e.g. “everybody @mit.edu”.

Made by the team at Weld (www.weld.io), the code-free app and web creation tool:

How to Run

Just start with:

# Set password used in API requests
export API_PASSWORD=MYPASSWORD

grunt

Server will default to http://localhost:3014

Entities

Coupon

• _id (string)
• created (date)

Qualifiers:

• code (string): the coupon code. Will be generated if not provided when coupon created.
• email (string): a partial email address (e.g. all with ".edu" in email gets the discount).

Constraints:

• duration (string): One of 'forever', 'once', and 'repeating'. Describes how long a customer who applies this coupon will get the discount.
• duration_in_months (positive integer): If duration is 'repeating', the number of months the coupon applies. Null if coupon duration is forever or once.
• duration_ends (read-only date): If duration is 'repeating', this is the end date.
• redeem_by (date): Date after which the coupon can no longer be redeemed
• max_redemptions (positive integer): Maximum number of times this coupon can be redeemed, in total, before it is no longer valid.
• times_redeemed (read-only positive integer) or zero: Number of times this coupon has been applied to a customer.
• valid (read-only boolean): Taking account of the above properties, whether this coupon can still be applied to a customer

What is rewarded:

• percent_off (positive integer): Percent that will be taken off the subtotal of any invoices for this customer for the duration of the coupon. For example, a coupon with percent_off of 50 will make a kr100 invoice kr50 instead.
• amount_off (positive integer): Amount (in the currency specified) that will be taken off the subtotal of any invoices for this customer.
• currency (currency): If amount_off has been set, the currency of the amount to take off.
• metadata: A set of key/value pairs that you can attach to a coupon object. It can be useful for storing additional information about the coupon in a structured format.

Discount (i.e. the application of a coupon to a particular user)

{
	user, // a user ID you can refer to (String)
	code, // Coupon code
	coupon, // associated Coupon object
	start, // start date (Date)
	end, // end date (Date)
}

REST API

Coupons

List coupons

curl http://localhost:3014/api/coupons?password=MYPASSWORD

Check/get available coupon (return code 404 if not found, 412 if found but not applicable)

curl http://localhost:3014/api/coupons/MYCOUPON?password=MYPASSWORD
// The ‘@’ in email is needed to determine to look for an email-based coupon
curl http://localhost:3014/api/coupons/@mit.edu?password=MYPASSWORD

Create new coupon:

curl -X POST -H "Content-Type: application/json" -d '{ "code": "MYCOUPON", "percent_off": 10 }' http://localhost:3014/api/coupons?password=MYPASSWORD

// Email-based: when create discount, if user’s email contains “mit.edu”, discount will be applied
curl -X POST -H "Content-Type: application/json" -d '{ "email": "mit.edu", "percent_off": 10 }' http://localhost:3014/api/coupons?password=MYPASSWORD

// Example: provide free services in a coupon
curl -X POST -H "Content-Type: application/json" -d '{ "code": "FREESERVICES", "metadata": { "subscriptions": [{ "id": "unlimited_projects" }] } }' http://localhost:3014/api/coupons?password=MYPASSWORD

Update coupon:

curl -X PUT -H "Content-Type: application/json" -d '{ "duration": "repeating", "duration_in_months": 6 }' http://localhost:3014/api/coupons/MYCOUPON?password=MYPASSWORD

Delete coupon:

curl -X DELETE http://localhost:3014/api/coupons/MYCOUPON?password=MYPASSWORD

Delete all coupons:

curl -X DELETE http://localhost:3014/api/coupons/ALL?password=MYPASSWORD

Discounts

List applied discounts for a user:

curl http://localhost:3014/api/discounts?password=MYPASSWORD&user=548cbb2b1ad50708212193d8

Apply/create new discount:

curl -X POST -H "Content-Type: application/json" -d '{ "code": "MYCOUPON", "user": "548cbb2b1ad50708212193d8" }' http://localhost:3014/api/discounts?password=MYPASSWORD
curl -X POST -H "Content-Type: application/json" -d '{ "email": "@mit.edu", "user": "548cbb2b1ad50708212193d8" }' http://localhost:3014/api/discounts?password=MYPASSWORD

Delete discount:

curl -X DELETE http://localhost:3014/api/discounts/50708212193d8?password=MYPASSWORD

Delete all discounts for a user:

curl -X DELETE http://localhost:3014/api/discounts/USER?password=MYPASSWORD&user=548cbb2b1ad50708212193d8

Delete all discounts:

curl -X DELETE http://localhost:3014/api/discounts/ALL?password=MYPASSWORD

Implementation

Built on Node.js, Express, and MongoDB.

Deploying on Heroku

# Set up and configure app
heroku create MYAPPNAME
heroku addons:create mongolab
heroku config:set NODE_ENV=production

# Set password used in API requests
heroku config:set API_PASSWORD=MYPASSWORD