URL Builder Pattern

URLBuilderPattern.swift

protocol ScopeFunc {}
extension ScopeFunc {
    @inline(__always) func apply(block: (Self) -> ()) -> Self {
        block(self)
        return self
    }
}

class URLBuilder: ScopeFunc {
    private var components = URLComponents()

    func set(scheme: String) -> URLBuilder {
        self.components.scheme = scheme
        return self
    }

    func set(host: String) -> URLBuilder {
        apply { $0.components.host = host }
    }

    func set(port: Int) -> URLBuilder {
        apply { $0.components.port = port }
    }

    func set(path: String) -> URLBuilder {
        var path = path
        if !path.hasPrefix("/") {
            path = "/" + path
        }
        self.components.path = path
        return self
    }

    func addQueryItem(name: String, value: String) -> URLBuilder  {
        if self.components.queryItems == nil {
            self.components.queryItems = []
        }
        self.components.queryItems?.append(URLQueryItem(name: name, value: value))
        return self
    }
 
    func build() -> URL? {
        return self.components.url
    }
}

let url = URLBuilder()
    .set(scheme: "https")
    .set(host: "localhost")
    .set(path: "api/v1")
    .addQueryItem(name: "sort", value: "name")
    .addQueryItem(name: "order", value: "asc")
    .build()

print(url)