Klimt

At Artsy, we often need to query REST endpoints and transform that data into another format needed by the client.

In this exercise, we provide a sample API with two endpoints and ask you to write some code to request data from the API and transform the response. We provided tests and starter files in Javascript and Ruby, but feel free to use a language of your choice.

Setup

Javascript

Requirements: NodeJS >= 10, yarn

yarn install to install.

ruby api/server.rb to run the server, then yarn test to run the provided unit tests.

Ruby

bundle install to install.

ruby api/server.rb to run the server, then bundle exec rspec test/client_spec.rb to run the provided unit tests.

TODO

Write test script to run server and test files

Artworks API

You'll be provided with a /artworks API endpoint that returns a JSON array of items in the following format:

[
  {
    "id": 1,
    "dominant_color": "brown",
    "availability": "sold",
    "artist_id": 3
  },
  {
    "id": 2,
    "dominant_color": "green",
    "availability": "for_sale",
    "artist_id": 1
  }
]

Each item returned from the /artworks endpoint will have the following:

id: A unique integer
dominant_color: One of "red", "brown", "blue", "yellow", or "green"
availability: Either "for_sale" or "sold"

The /artworks endpoint accepts the following options, sent as query string parameters on the request URL:

limit: The number of items to be returned
offset: The index of the first item to be returned
dominant_color[]: Which color to be included in the result set. May be included multiple times, once for each color. If omitted, all dominant_color values will be returned.

An example request URL might look like:

/artworks?limit=2&offset=0&dominant_color[]=brown&dominant_color[]=green

Artist API

You'll also be provided with a /artist API endpoint that returns a JSON hash in the following format:

{
  "id": 1,
  "name": "Gustav Klimt"
}

The hash returned from the /artist endpoint will have the following:

id: A unique integer
name: A string indicating the name of the artist

The /artist endpoint accepts the following options, sent as query string parameters on the request URL:

id: Unique integer linked to an artist

An example request URL might look like:

/artist?id=3

Task

In client/client.js or client/client.rb, write a function named retrieve that requests data from the /artworks endpoint, transforms the result into the format outlined below, and returns a promise that resolves with the transformed object. In addition to retrieve, you may add as many helper functions as you wish.

Get data from the /artworks endpoint. Process pages of 10 items at a time. Note that the /artworks endpoint may return more than 10 items per request.
The retrieve function accepts an options object and should support the following keys:

page - Specifies which page to retrieve from the /artworks endpoint. If omitted, fetch page 1.
dominant_color - An array of dominant colors to retrieve from the /artworks endpoint. If omitted, fetch all dominant colors.

As an example, to fetch the 2nd page of red and brown items from the API, retrieve might be called like this:
```
retrieve({ page: 2, dominant_color: ["red", "brown"] });
```

You can assume standard HTTP status codes on the response. If a request is unsuccessful, output a simple error message via console.log() or puts and recover.
Upon a successful API response, transform the fetched payload into an object containing the following keys:

ids: An array containing the ids of all items returned from the request.
for_sale: An array containing all of the items returned from the request that have a availability value of "for_sale". Add a fourth key to each item called isPrimary indicating whether or not the item contains a primary color (red, blue, or yellow).
soldPrimaryCount: The total number of items returned from the request that have a availability value of "sold" and contain a primary color.
artistNames: An array containing all the artists associated with the items returned from the request sorted alphabetically by full name.
previousPage: The page number for the previous page of results, or null if this is the first page.
nextPage: The page number for the next page of results, or null if this is the last page.

For the Javascript exercise, return a promise from retrieve that resolves with the transformed data. For the Ruby exercise, return a Hash with the transformed data.

Additional requirements

Use the provided URI library to construct the request URL. Refer to https://medialize.github.io/URI.js/ for documentation.
For the Javascript option, you should use the Axios API to interact with the artworks endpoint. Refer to https://axios-http.com/docs/intro for documentation.
For the Ruby option, you should use the REST Client library to interact with the artworks endpoint. Refer to https://rubydoc.info/github/rest-client/rest-client/master for documentation.
Don't add any additional libraries or edit any files other than client/client.js or client/client.rb
We've provided a suite of unit tests. Your solution should pass all tests.

Credit

This has been generously inspired by the exercise from Ad Hoc

artsy/klimt