Nubank Authorizer

The nubank-authorizer is a micro-service designed to register account and transactions. The service is consumed via the api interface, using json to traffic the payload objects.

Verb	URI	Action
POST	/accounts	Create an account
POST	/transactions	New transaction

Project design

The project design follows the clean code principle with SOLID concepts. The directory layout follows the golang-standards/project-layout with some adaptations to make the project simpler, like go.

Get Started

This project considers that you have installed these tools:

• Make
• Docker
• Docker Compose

First, you can run all the tests. Will ensure that everything is working.

$ make test

?       nubank/authorizer                 [no test files]
?       nubank/authorizer/database        [no test files]
ok      nubank/authorizer/database/memory 0.002s  coverage: 100.0% of statements
ok      nubank/authorizer/entity          0.001s  coverage: 100.0% of statements
ok      nubank/authorizer/handler         0.005s  coverage: 100.0% of statements
ok      nubank/authorizer/usecase         0.002s  coverage: 100.0% of statements

To run the service locally using docker and compose, execute:

$ make up

Now, send a request to localhost:3000 using get verb.

$ curl localhost:3000

The result is:

{
  "content": "nubank authorizer api"
}

To following container logs, execute:

$ make logs

Create an account

To create a newaccount send a post to /accounts, for example:

$ curl -X POST http://localhost:3000/accounts \
  -d '{"account": {"activeCard": true, "availableLimit": 100}}'

Register new transaction

To register a new transactions send a post to /transactions, like:

$ curl -X POST http://localhost:3000/transactions \
  -d '{"transaction": {"merchant": "ifood", "amount": 25, "time": "2020-12-22T10:00:00.000Z"}}'

Basic Use Case

# create an account
$ curl -X POST http://localhost:3000/accounts \
  -d '{"account": {"activeCard": true, "availableLimit": 100}}'

{"account":{"activeCard":true,"availableLimit":100},"violations":[]}

# account-already-initialized rule
$ curl -X POST http://localhost:3000/accounts \
  -d '{"account": {"activeCard": true, "availableLimit": 350}}'

{"account":{"activeCard":true,"availableLimit":100},"violations":["account-already-initialized"]}

# create an transaction
$ curl -X POST http://localhost:3000/transactions \
  -d '{"transaction": {"merchant": "Burger King", "amount": 20, "time": "2019-02-13T10:00:00.000Z"}}'

{"account":{"activeCard":true,"availableLimit":80},"violations":[]}

# doubled transaction rule
$ curl -X POST http://localhost:3000/transactions \
  -d '{"transaction": {"merchant": "Burger King", "amount": 20, "time": "2019-02-13T10:02:00.000Z"}}'

{"account":{"activeCard":true,"availableLimit":80},"violations":["doubled-transaction"]}

# insuficient limit rule
$ curl -X POST http://localhost:3000/transactions \
  -d '{"transaction": {"merchant": "Burger King", "amount": 200, "time": "2019-02-13T10:00:00.000Z"}}'

{"account":{"activeCard":true,"availableLimit":80},"violations":["insufficient-limit"]}

Helper

execute make help to show details about makefile tasks:

$ make help
usage: make [target]

development:
  build                           Build docker images.
  up                              Run containers in detach.
  restart                         Restart development environment.
  stop                            Stop development environment and remove containers orphans.
  logs                            Follows development logs.
  shell                           Start a shell session within the container.

lint:
  lint                            Run static analysis code.

other:
  one-shot                        Execiute basic use case using curl.
  help                            Show this help.

test:
  test                            Run the tests.
  coverage                        Generate coverage files.

Challenge description

For more information about the challenge, see here