pknn/humorous-api

Humorous API

Endpoints

• /healthcheck: always return 200
• /colors: return 5 random colors from random available color spaces

Responses

• Color

{
  "type": "RGB" | "HSL",
  "components": string[] // "{value}{unit}" -> "30" or "50%"
}

Extending Color space

You'll only need to touch model/color/color.ts (and test) to extend color space

1. Add new color space type to AvailableColorKeys, this will then add literal type to AvailableColorKey type

export const AvailableColorKeys = ['RGB', 'HSL', 'BRGB'] as const
export type AvailableColorKey = typeof AvailableColorKeys[number] 
                                // Now 'RGB' | 'HSL' | 'BRGB'

2. Add new color class extending Color with static getRandomColor() method

export class BRGB extends Color {
  constructor(...colorValues: [ColorValue, ColorValue, ColorValue]) {
    super(
      'BRGB',
      { unit: ColorUnit.Literal, value: colorValues[0] },
      { unit: ColorUnit.Literal, value: colorValues[1] },
      { unit: ColorUnit.Literal, value: colorValues[2] },
    )
  }

  static getRandomColor() {
    return new BRGB(
      getRandomNumber(0, 9999),
      getRandomNumber(0, 9999),
      getRandomNumber(0, 9999),
    )
  }
}

3. Add your class to AvailableColors

export const AvailableColors = [RGB, HSL, BGRB]

4. Implement some test for this new Color, then "BOOM" API part is done.

Design Challenges

DC#1: RGB and HSL has different representation in terms of Unit (RGB as literal, HSL with saturation and lightness as percentage)

Solution: Design Color component in the model as {unit: ColorUnit, value: ColorValue}, and use presenter to combined unit and value into one for ease of use in the front end side

DC#2: Other color space may have any number of color components (RGBA with 4 color components)

Solution: Storing color component as a list extends compatibilty to color space with any number of color components

Potential improvements

1. Redundant hard-coded minimum and maximum possible value of each component, might be able to lift it out or reuse it somehow.
2. static random color getter is not shared amoung the subclasses, each getRandomeColor is its own static method, with AvailableColors as a bridge.