Fetchable. For article: https://medium.com/p/4ddf8710d1a0/

Fetchable.swift

public protocol Fetchable {
    
    // Required. No default values:
    
    /// The type of the object in the response.
    associatedtype Fetched
    
    /// The type of the failure object in the response.
    associatedtype FetchedFailure
    
    /// The parameter keys, to be used in the request.
    associatedtype Key: FetchKey
    
    /// The base URL for the request. Typically `URL("https://host/common_path/")!`
    static var baseURL: URL { get }
    
    // Can override. Default values:
    
    /// End point first path component. Defaults to `nil`.
    static var startURLPath: String? { get }
    
    /// End point last path component. Defaults to lowercase of `Fetched` type.
    static var endURLPath: String? { get }
    
    /// Defaults to `.get`. Can also be `.post`.
    static var httpMethod: Fetch.HTTPMethod { get }
    
    /// Defaults to `.form` when `httpMethod` = `.get` and `.json` when `httpMethod` = `.post`.
    static var encoding: Fetch.Encoding { get }
    
    /// Defaults to nil.
    static var headers: [String: String]? { get }
    
    /// Defaults to `JSONDecoder` with `dateDecodingStrategy` = `.iso8601`. Can change to `.sqlDate` or `.tTimezone` or `.timezone` or custom.
    static var decoder: JSONDecoder { get }
    
    /// Default key values, such as an API key or authorization. Defaults to empty.
    static var defaultKeyValues: [Key : FetchValue] { get }
    
}