/restaurant-api

Small application on Scala

Primary LanguageScala

Restaurant API

This project follows a hexagonal architecture to uncouple the responsibilities from the business logic and the frameworks/libraries.

Deploy

# I would like to change the image creation to a multistage docker in order to reduce the image size as much as
# possible. But since I'm not that versed on scala I decided to use an automatic packager.
$ sbt docker:publishLocal
# To deploy it on k8s (prepared for the k8s docker-desktop)
$ kubectl apply -f deploy/k8s.yml
# To use it in plain docker
$ docker run --rm -p 8080:8080 restaurant-api:0.0.1-SNAPSHOT

HTTP method allowed

Method Description
GET Get a resource or get a list of resources
POST Create a resource
DELETE Delete a resource

Code Response

Code Description
200 Success
201 Success - new resource build.
204 Success - there is not a resource to response
400 Bad Request - i.e. invalid request
401 Unauthorized - no token for this resource
404 Not Found - resource doesn't exist
422 Unprocessable Entity - i.e. validation error
429 Request exceeded the limit
500 Server error
503 Server holidays

Create a new order

POST /order (201)

{
    "name": name,
    "tableId": table-id
}

Response

{
    "id": "10b50670-e10e-4b30-9adb-d7034ee4bbc1",
    "name": "test",
    "tableId": "t1",
    "orderAt": timestamp,
    "minutesToReady": 7
}

Get a order by order & table id

GET /table/{table:id}/order/{order:id}

Response

{
    "id": "10b50670-e10e-4b30-9adb-d7034ee4bbc1",
    "name": "test",
    "tableId": "t1",
    "orderAt": timestamp,
    "minutesToReady": 7
}

Delete a order by order & table id

DELETE /table/{table:id}/order/{order:id} (204)

Get a list of items by table id

GET /table/{table:id}

Response

[
    {
        "id": "10b50670-e10e-4b30-9adb-d7034ee4bbc1",
        "name": "test",
        "tableId": "t1",
        "orderAt": timestamp,
        "minutesToReady": 7
    },
    {
        "id": "9dc99de5-6596-4b26-a11a-494ee5604a41",
        "name": "test2",
        "tableId": "t1",
        "orderAt": timestamp,
        "minutesToReady": 7
    }
    ...
]

Client

We are using k6 as a client. Grafana k6 is an open-source load testing tool where we can set multiple sync/async clients.

Install

$ cd client
$ npm install
# You may need to create the /out folder
$ mkdir out

Run

$ npm start

FAQ

Why K8S and not AWS lambdas?

P 1: When using Serverless platforms the first invocation of a function takes some time since the code needs to be initialized. In this case we will need a fast response since this service will be integrated with a stack of MS.

P 2: Kubernetes might provide better scalability features than some Serverless platforms, since Kubernetes is more mature and provides even HA (high availability) between different zones which not all Serverless platforms provide yet.

P 3: it might be easier to use Kubernetes for more complex applications because the platform is more mature. And since we are planning to use a database to store the outcome of the logic, that make sense.

P 4: Serverless doesn’t automatically mean lower costs, like when your applications need to run 24/7. There can also be some hidden costs like extra costs for API management or the costs for the function invocations for tests.

P 5: The monitoring capabilities of Kubernetes applications are much more mature.