Как реализовать OAuth2 на React Native Expo?

Auth.login('user_login', 'user_password')
		.then((response) => {
    		if (response.status === 200) {
	            Promise.all([
	            	// Записываем полученные данные
	            	let exp_time = new Date().getTime() + response.data.expires_in * 1000;

	            	SecureStore.setItemAsync('access_token', response.data.access_token),
	            	SecureStore.setItemAsync('refresh_token', response.data.refresh_token),
	            	SecureStore.setItemAsync('expiration_time', exp_time.toString()),
	            ])
	            .then(() => doSomething());
	          } else {
	            // обработать ошибку
	          }
    	});

export default class Auth {
		  static async getAccessToken() {
		    let access_token = await SecureStore.getItemAsync('access_token');
		    let refresh_token = await SecureStore.getItemAsync('refresh_token');
		    let expiration_time = await SecureStore.getItemAsync('expiration_time');

		    let is_exipired = false;
		    if(new Date().getTime() < expiration_time) {
		    	is_exipired = true;
		    }

		    if (!is_exipired) {
		    	// выдать старый токен
		      	return access_token;
		    } else {
		      return this.refreshAccessToken(refresh_token)
		          .then((response) => {
		            if (response.status === 200) {
		              	// записать новые данные
		              	let exp_time = new Date().getTime() + response.data.expires_in * 1000;

		              	SecureStore.setItemAsync('access_token', response.data.access_token),
		            	SecureStore.setItemAsync('refresh_token', response.data.refresh_token),
		            	SecureStore.setItemAsync('expiration_time', exp_time.toString()),

		            	// выдать новый токен
						return response.data.access_token;
		            } else {
		              // токен обновить не получилось - разлогинить в приложении

		              return null;
		            }
		          });
		    }
		  }

		  static refreshAccessToken(refresh_token) {
		    let params = {
		      grant_type: 'refresh_token',
		      refresh_token: refresh_token,
		      client_id: 'api_client_id',
		      client_secret: 'api_client_secret',
		    };

		    return Api.callMethod('oauth/token', params, 'post');
		  }

		  static login(username, password) {
		    let params = {
		      grant_type: 'password',
		      username: username,
		      password: password,
		      client_id: 'api_client_id',
		      client_secret: 'api_client_secret',
		      scope: 'profile',
		    };

		    return Api.callMethod('oauth/token', params, 'post');
		  }

		  static logout(parameters = {}) {
		    return Auth.getAccessToken()
		        .then((access_token) => {
		          parameters['token'] = access_token;
		          return Api.callMethod('oauth/revoke', parameters, 'post');
		        });
		  }
		}

export default class Api {
	  static async callMethod(path, parameters = {}, method = 'get', headers = {}) {
	    headers = {
	      'Accept': 'application/json',
	      'Content-Type': 'application/x-www-form-urlencoded',
	      ...headers,
	    };

	    if (typeof parameters.access_token !== 'undefined') {
	      headers['Authorization'] = 'Bearer ' + parameters.access_token;
	      delete parameters.access_token;
	    }

	    let request = {
	      method: method,
	      url: 'https://httpbin.org/' + path,
	      headers: headers,
	      responseType: 'json',
	      data: parameters,
	    };

	    return axios(request)
	    	.then((response) => {
	      		return response;
	    	});
	  }
	}

export default class User {
	  static me(parameters = {}) {
	    return Auth.getAccessToken()
	        .then((access_token) => {
	          parameters['access_token'] = access_token;
	          return Api.callMethod('me', parameters);
	        });
	  }
	}