https://github.com/choochmeque/simplegooglesignin
Lightweight, zero-dependency Google Sign-In for iOS.
https://github.com/choochmeque/simplegooglesignin
authentication google-signin-api ios oauth2 pkce swift swift-package-manager zero-dependency
Last synced: about 1 month ago
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Lightweight, zero-dependency Google Sign-In for iOS.
- Host: GitHub
- URL: https://github.com/choochmeque/simplegooglesignin
- Owner: Choochmeque
- License: mit
- Created: 2025-09-03T14:40:52.000Z (10 months ago)
- Default Branch: main
- Last Pushed: 2025-11-02T19:21:18.000Z (8 months ago)
- Last Synced: 2025-11-02T21:13:07.807Z (8 months ago)
- Topics: authentication, google-signin-api, ios, oauth2, pkce, swift, swift-package-manager, zero-dependency
- Language: Swift
- Homepage:
- Size: 23.4 KB
- Stars: 0
- Watchers: 0
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Funding: .github/FUNDING.yml
- License: LICENSE
Awesome Lists containing this project
README
# SimpleGoogleSignIn
A lightweight, dependency-free Google Sign-In implementation for iOS in pure Swift.
## Features
✅ **Zero external dependencies** - Uses only iOS system frameworks
✅ **Modern OAuth 2.0 with PKCE** - Secure authentication flow
✅ **Token management** - Access, refresh, and ID token handling
✅ **Simple API** - Easy to integrate and use
✅ **SwiftUI & UIKit** - Compatible with both frameworks
✅ **Token refresh** - Built-in refresh token support
## Requirements
- iOS 13.0+
- Swift 5.7+
- Xcode 14.0+
## Installation
### Swift Package Manager
Add this package to your project:
```swift
dependencies: [
.package(url: "https://github.com/Choochmeque/SimpleGoogleSignIn.git", from: "1.0.0")
]
```
Or in Xcode:
1. File → Add Package Dependencies
2. Enter the repository URL
3. Select "SimpleGoogleSignIn" library
### Manual Installation
Simply copy `SimpleGoogleSignIn.swift` to your project. No dependencies needed!
## Setup
### 1. Get Google OAuth 2.0 Credentials
1. Go to [Google Cloud Console](https://console.cloud.google.com/)
2. Create a new project or select existing
3. Enable Google Sign-In API
4. Create OAuth 2.0 credentials (iOS application)
5. Add your bundle ID
6. Copy the Client ID
### 2. Configure URL Scheme
Add to your `Info.plist`:
```xml
CFBundleURLTypes
CFBundleURLSchemes
com.googleusercontent.apps.YOUR_CLIENT_ID
```
### 3. Handle URL Callbacks
In your `AppDelegate` or `SceneDelegate`:
```swift
func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
return SimpleGoogleSignIn.shared.handleURL(url)
}
```
## Usage
### Configuration
```swift
import SimpleGoogleSignIn
// Configure on app launch
let configuration = GoogleSignInConfiguration(
clientID: "YOUR_CLIENT_ID.apps.googleusercontent.com",
serverClientID: nil, // Optional: for server-side validation
hostedDomain: nil // Optional: restrict to specific domain
)
SimpleGoogleSignIn.shared.configure(configuration: configuration)
```
### Sign In
```swift
SimpleGoogleSignIn.shared.signIn(
presentingViewController: viewController,
hint: nil, // Optional: pre-fill email address
scopes: ["openid", "profile", "email"] // Required: OAuth scopes
) { result in
switch result {
case .success(let signInResult):
print("Access Token: \(signInResult.accessToken.tokenString)")
print("ID Token: \(signInResult.openIdToken ?? "")")
print("Refresh Token: \(signInResult.refreshToken ?? "")")
print("Granted Scopes: \(signInResult.grantedScopes ?? [])")
case .failure(let error):
print("Sign in failed: \(error)")
}
}
```
### Sign Out
```swift
// Sign out and optionally revoke access token
SimpleGoogleSignIn.shared.signOut(accessToken: accessTokenString) { error in
if let error = error {
print("Sign out failed: \(error)")
} else {
print("Successfully signed out")
}
}
// Or sign out without revoking token
SimpleGoogleSignIn.shared.signOut(accessToken: nil) { error in
// Local sign out only
}
```
### Token Refresh
```swift
// Refresh tokens using refresh token
SimpleGoogleSignIn.shared.refreshTokens(refreshToken: refreshTokenString) { result in
switch result {
case .success(let signInResult):
print("New Access Token: \(signInResult.accessToken.tokenString)")
print("Token expires: \(signInResult.accessToken.expirationDate ?? Date())")
// Note: refreshToken may be the same as the original
case .failure(let error):
print("Refresh failed: \(error)")
}
}
```
### Check Token Expiration
```swift
// GoogleToken provides expiration checking
if accessToken.isExpired {
// Token has expired, refresh it
}
```
## SwiftUI Example
```swift
import SwiftUI
import SimpleGoogleSignIn
struct ContentView: View {
@State private var signInResult: GoogleSignInResult?
@State private var isSigningIn = false
var body: some View {
VStack(spacing: 20) {
if let result = signInResult {
Text("Signed In Successfully")
Text("Access Token: ...\(String(result.accessToken.tokenString.suffix(10)))")
Button("Sign Out") {
SimpleGoogleSignIn.shared.signOut(accessToken: result.accessToken.tokenString) { _ in
signInResult = nil
}
}
} else {
Button("Sign in with Google") {
signIn()
}
.disabled(isSigningIn)
}
}
.padding()
}
private func signIn() {
isSigningIn = true
guard let windowScene = UIApplication.shared.connectedScenes.first as? UIWindowScene,
let rootViewController = windowScene.windows.first?.rootViewController else {
return
}
SimpleGoogleSignIn.shared.signIn(
presentingViewController: rootViewController,
hint: nil,
scopes: ["openid", "profile", "email"]
) { result in
isSigningIn = false
switch result {
case .success(let result):
signInResult = result
case .failure(let error):
print("Sign in failed: \(error)")
}
}
}
}
```
## UIKit Example
```swift
import UIKit
import SimpleGoogleSignIn
class SignInViewController: UIViewController {
private var signInResult: GoogleSignInResult?
override func viewDidLoad() {
super.viewDidLoad()
configureGoogleSignIn()
}
private func configureGoogleSignIn() {
let configuration = GoogleSignInConfiguration(
clientID: "YOUR_CLIENT_ID.apps.googleusercontent.com"
)
SimpleGoogleSignIn.shared.configure(configuration: configuration)
}
@IBAction func signInTapped() {
SimpleGoogleSignIn.shared.signIn(
presentingViewController: self,
hint: nil,
scopes: ["openid", "profile", "email"]
) { result in
switch result {
case .success(let result):
self.signInResult = result
self.handleSignInSuccess(result)
case .failure(let error):
self.showError(error)
}
}
}
private func handleSignInSuccess(_ result: GoogleSignInResult) {
print("Access Token: \(result.accessToken.tokenString)")
// Navigate to main app or update UI
}
private func showError(_ error: Error) {
let alert = UIAlertController(
title: "Sign In Failed",
message: error.localizedDescription,
preferredStyle: .alert
)
alert.addAction(UIAlertAction(title: "OK", style: .default))
present(alert, animated: true)
}
}
```
## Comparison with Official GoogleSignIn
| Feature | SimpleGoogleSignIn | Official GoogleSignIn |
|---------|-------------------|---------------------|
| Dependencies | None | 6+ packages |
| Size | ~570 lines | Thousands of lines |
| Platform | iOS only | iOS, macOS |
| Setup Complexity | Simple | Complex |
| App Attest | ❌ | ✅ |
| EMM Support | ❌ | ✅ |
| Server Auth Code | ✅ | ✅ |
| Token Refresh | ✅ | ✅ |
| PKCE Support | ✅ | ✅ |
## Security Features
- **PKCE** (Proof Key for Code Exchange) for OAuth security
- **State parameter** verification to prevent CSRF attacks
- **Nonce** included in authentication for additional security
- **Token expiration** tracking and validation
- **SSL/TLS** for all network requests
- **ASWebAuthenticationSession** for secure system-level authentication
## Error Handling
```swift
enum GoogleSignInError: LocalizedError {
case missingConfiguration
case missingPresentingViewController
case authenticationFailed(String)
case invalidResponse
case userCancelled
case networkError(Error)
case missingURLScheme(String)
var errorDescription: String? {
switch self {
case .missingConfiguration:
return "Google Sign-In configuration is missing"
case .missingPresentingViewController:
return "No presenting view controller available"
case .authenticationFailed(let message):
return "Authentication failed: \(message)"
case .invalidResponse:
return "Invalid response from Google"
case .userCancelled:
return "User cancelled sign-in"
case .networkError(let error):
return "Network error: \(error.localizedDescription)"
case .missingURLScheme(let scheme):
return "Required URL scheme '\(scheme)' is not configured in Info.plist"
}
}
}
```
## License
MIT License - see [LICENSE](LICENSE) file for details.
## Contributing
Contributions are welcome! Please feel free to submit pull requests.
## Support
For issues or questions, please create an issue in the repository.