vincibean/offer-kata

My solution to the Offer kata

Offer Kata

Background

"an offer is a proposal to sell a specific product or service under specific conditions"

-- Wikipedia

Merchants offer goods for sale; they can create offers to share with their customers.

All the offers have shopper friendly descriptions. Offers are priced up front in a defined currency.

An offer is time-bounded, with the length of time an offer is valid for defined as part of the offer, and should expire automatically. Offers may also be explicitly cancelled before they expire.

Assignment

You are required to create a simple RESTful software service that will allow a merchant to create a new simple offer. Offers, once created, may be queried. After the period of time defined on the offer it should expire and further requests to query the offer should reflect that somehow. Before an offer has expired users may cancel it.

Assumptions

• No frontend development is necessary;
• Offers are modeled as "the place where merchants meet products": a merchant can propose products via offers only; this means that the same merchant can sell the same product using different offers (and, as such, prices); this should allow quite an high degree of flexibility;
• In order to provide a validity to an offer, we could have used a date (e.g. valid till the 9th of August) or a period (e.g. valid for the next 3 weeks): we preferred the date approach, as we deemed it more intuitive and user-friendly;
• We don't need a fine-grained approach to dates (e.g. valid till the 17:00 of the 9th of August);
• canceling a valid offer means that, from the given moment, that offer isn't valid anymore;
• canceling an already invalid offer must trigger an error message;
• We didn't deal with timezones: we give for granted that the fronted will deal with that;
• When deserializing a JSON containing a currency, if the currency is unknown, we default it to USD (currencies from all over the world are covered, though);
• Error messages aren't localized;
• We use JSON for requests/responses: it can be safely considered the standard nowadays;

How to run it

This project uses the flyway-sbt and slick-codegen plugins, hence you have to make sure that the flywayMigrate task has been executed first.

Tests

sbt flywayMigrate test

Integration Tests

sbt flywayMigrate it:test

Run Main

sbt flywayMigrate run

Bash Scripts

For your convenience, two bash scripts were created:

• run.sh: runs the main class;
• test.sh: runs the integration tests, and then the unit tests.

Postman REST Collection

For your convenience, a Postman Collection was created for you here

CURL commands

List all valid offers:

curl --request GET --url http://localhost:8080/offers

Create a new offer:

curl --request POST --url http://localhost:8080/offers --header "Content-Type: application/json" --data '{"id": "acaab7e9-bab9-416c-99e9-63ce74dbd3a8","product": {"id": "e3712f03-bfd6-45b0-b120-a7d90d44bc23","name": "mockProduct","description": "a mock product"},"merchant": {"id": "b4aefced-fef0-4c0b-9451-b70091b1386c","name": "a mock merchant"},"description": "s1","money": {"currency": "USD","amount": 42},"validTill": {"year": 2018,"month": 8,"dayOfMonth": 26}}'

List a specific offer (the one we just created):

curl --request GET --url http://localhost:8080/offers/acaab7e9-bab9-416c-99e9-63ce74dbd3a8

Cancel a specific offer (the one we just created):

curl --request PATCH --url http://localhost:8080/offers/acaab7e9-bab9-416c-99e9-63ce74dbd3a8 --header "Content-Type: application/json" --data {}