Gravity

SwiftUI library for data fetching

Lightweight

Any Backend

Realtime

Designed for SwiftUI

SwiftPM Ready

WebSocket support

Gravity is a SwiftUI library for remote data fetching. It uses stale-while-revalidate technonology to fetch data from the server, a cache invalidation strategy popularized by HTTP RFC 5861. Gravity first returns the data from cache (stale), then sends the fetch request (revalidate), and finally comes with the up-to-date data again.

✅

With Gravity, components will get a stream of data updates constantly and automatically. And the UI will be always fast and reactive.

Overview

import SwiftUI
import Gravity


struct LandmarkList: View {
    @SWR<URL, Landmark>(url: "https://example.org/api/endpoint", model: Landmark) var api
    var body: some View {
        if let landmarks = api.data {
            List(landmarks, id: \.id) { landmark in
                LandmarkRow(landmark: landmark)
            }
        }
    }
}

In this example, the property wrapper @SWR accepts a url and a model.

The url is the URL of the API. And the model is a Codable object.

api will be a StateResponse object that has three children: data that will contain the decoded data, error in case there is an error and awaiting when the app is loading.