buster84/scala_a1

Smartcloud instance prices API

How to run

Prerequisites

• Java (>=8)
• sbt

Run

• Run the server. Http port can be changed by config

sbt run

The API should be running on your port 8080 for default.

API endpoints

Instance kinds

• URL: GET /instance-kinds
• Success Response:

[
    {
        "kind": "sc2-micro"
    },
    {
        "kind": "sc2-small"
    },
... (ommitted)
    {
        "kind": "sc2-hicpu-32"
    }
]

Prices

Return prices of all instances. If kind is specified, the prices of the given instance kinds are returned.

• URL: GET /prices
• Parameters:
  • Optional:
    • kind=[string] : The value is one or multiple instance kinds. For multiple instance kinds, you can specify multiple instance kinds by comma separation. For example, /prices?kind=sc2-hicpu-32,sc2-small,sc2-micro
• Success Response:

[
    {
        "kind": "sc2-micro",
        "price": 0.301
    },
    {
        "kind": "sc2-small",
        "price": 0.561
    },
... (ommited)
    {
        "kind": "sc2-hicpu-32",
        "price": 0.925
    }
]

Assumption and design

Assumption

• /prices should return multiple prices. It is not clear by the requirements but returning one prices is subset of multiple one so I hope this is fine.
• 500 error of the smartcloud can be fixed in next 3 times calling the api.

Design

• One of smarcloud api calls returns 422 error, this api returns 422 error instead of returning prices partially. I choose this way because this way is simpler for callee of this API.
• Set retry policy for http client without waiting
• Use ApplicativeError instead Either. This is because of keeping original type.
• Set errorHandle in the routes instead of getPrices and getInstanceKinds because we may forget to set errorHandle in the new route method if we add a new endpoint.
• I did case ex : PriceService.Exception in the errorHandle because we can get exhaustive type checking benefit by sealed trait.