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content/Frontend/React Native/OAuth2 login.md

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+Use #oauth2 login with React-Native
+
+## Common OAuth2 providers
+
+Can be handled by [react-native-app-auth](react-native-app-auth) by redirecting to url `com.yourapp://oauth2provider`. 
+
+### Example for #Google
+
+```typescript
+import { authorize } from 'react-native-app-auth';
+
+const GOOGLE_OAUTH_CLIENT = '...';
+
+// ...
+const authState = await authorize({
+  issuer: 'https://accounts.google.com',
+  clientId: `${GOOGLE_OAUTH_CLIENT}.apps.googleusercontent.com`,
+  redirectUrl: `com.yourapp:/oauth2redirect/google`,
+  scopes: ['openid', 'profile'],
+  dangerouslyAllowInsecureHttpRequests: true,
+});
+```
+
+### Example for #Yandex
+
+```typescript
+const YANDEX_OAUTH_CLIENT = '...';
+const YANDEX_OAUTH_SECRET = '...'; // better hide it somehow
+const APP_ID = 'com.yourapp';
+
+const authState = await authorize({
+  serviceConfiguration: {
+    authorizationEndpoint: `https://oauth.yandex.ru/authorize?response_type=code&client_id=${YANDEX_OAUTH_CLIENT}&redirect_uri=${APP_ID}:/oauth2redirect`,
+    // TODO: replace it with your own backend to secure client_secret:
+    tokenEndpoint: `https://oauth.yandex.ru/token?grant_type=authorization_code&client_id=${YANDEX_OAUTH_CLIENT}&client_secret=${YANDEX_OAUTH_SECRET}`,
+  },
+  clientId: YANDEX_OAUTH_CLIENT,
+  redirectUrl: `${APP_ID}:/oauth2redirect`,
+  scopes: ['login:info', 'login:avatar'],
+  dangerouslyAllowInsecureHttpRequests: true,
+});
+
+callback(authState.accessToken);
+```
+
+## Apple ID login
+
+[react-native-apple-authentication](https://github.com/invertase/react-native-apple-authentication) has its own [documentation](https://github.com/invertase/react-native-apple-authentication/tree/main/docs) on setting up OAuth using Apple ID.