This project is a demo intended to test the integration concept of OAuth2, Spring Boot, and Vaadin Flow with the Google Calendar API

Before running this project, make sure to have the following properties configured in the application.properties file:

account.google.client-id:${ACCOUNT_GOOGLE_CLIENT_ID:...}
account.google.client-secret:${ACCOUNT_GOOGLE_SECRET:...}
account.google.redirect-uri:${ACCOUNT_GOOGLE_REDIRECT_URI:https://.../api/google/callback}

Replace the ... values with your Google account configuration. You can follow the Google Calendar API Quickstart guide to obtain these values.

To correctly configure OAuth2 credentials in the Google Console, follow these steps:

1. Create a new project: Create a new project in the Google Console for your application.
2. Enable the API: Enable the corresponding API, in this case, the Google Calendar API.
3. Configure OAuth consent: Configure the OAuth consent screen with your application details.
4. Authorize credentials for a web application: Create OAuth2 credentials of type OAuth 2.0 Client IDs for a web application and ensure to provide the correct redirect URI.

To generate the correct redirect URI, you need an https protocol. To achieve this, we can use ngrok.

To ensure the correct functioning of the Webhook in the OAuth 2.0 Client IDs section specifically in Authorized redirect URIs, it is mandatory to provide a URL with the HTTPS protocol. This is essential to maintain the security of communications between the server and the client application.

Steps to configure ngrok:

1. Download ngrok from ngrok.com
2. Unzip the downloaded file and start ngrok in your terminal by running the following command (replace PORT with the port your local server is running on):

ngrok http 54154

Ngrok will generate a public URL that you can use as the Authorized redirect URI in the Google Console.

With these configurations correctly set up in the Google Console and the corresponding values entered in the application.properties file, the application should function correctly after running the command

# Mac & Linux
./mvnw

# Windows
mvnw

Note:

• This demo focuses on Google Calendar to display holidays in the locality configured in the calendar. The visual part of Vaadin Flow displays these holidays to provide useful functionality to the user.

• Remember that this application is designed as a demonstration and can be extended to include more features and functionalities as needed.