How to Integrate Microsoft Outlook Calendar into Your Spring Boot Application

Integrating calendar functionality into your application can significantly enhance user experience and productivity. Microsoft Outlook Calendar is one of the most widely used calendar services, and integrating it into your app can provide users with seamless scheduling, event management, and reminders. In this blog, we’ll walk you through the process of integrating Microsoft Outlook Calendar into your app.

Why integrate Microsoft Outlook Calendar?

Integrating Microsoft Outlook Calendar into your app offers several benefits:

• Seamless scheduling: Users can manage their schedules directly within your app.

• Improved productivity: Sync events, reminders, and meetings with Outlook Calendar.

• Cross-platform compatibility: Outlook Calendar works across devices and platforms.

• Enhanced user experience: Provide a familiar and trusted calendar interface to your users.

How to integrate Outlook with Spring Boot

Before we start coding, you need to register the app in the Microsoft Entra admin center.

Register application for user authentication:

1. Open a browser, navigate to the Microsoft Entra admin center, and log in using a Global administrator account.

2. Select New registration. Enter a name for your application

3. Select Authentication under Manage. Locate the Advanced settings section and change the Allow public client flows toggle to Yes, then choose Save.

4. Note down the Client ID and Tenant ID.

How to set up your Java project

The next step is creating a Java app.

1. Install dependencies into your build.gradle

2. Update the values accordingly into your application.properties

3. Add user authentication

Configure Graph client for user authentication

Incorporate the Microsoft Graph into the application. In this section, we will use the DeviceCodeCredential class to request an access token by using the device code flow.

• DeviceCodeCredential: Handles the authentication process using the device code flow.

• GraphServiceClient: The main client for interacting with Microsoft Graph API.

• initializeGraphForUserAuth: Initializes the GraphServiceClient with the necessary credentials and scopes.

4. Create a Controller where you can call the connectToOutlook() method

Inside the console, a link, and code for authentication will be given to you.

Now you are able to authenticate to your Outlook account through the application.

Fetching calendar events

• Add the following code to your OutlookService

The function uses the request builder, which builds a request to the calendar API. In Request, we are using startDateTime and endDateTime to catch only a desired portion of our calendar.

• Add a getCalendar()method to your OutlookController.

This method will return you a response with all information for every event in your calendar. To make the response more readable and to get only fields that are useful to us, we will show an example method that can be refactored depending on the Objects you are using.

• Add the following code to your OutlookService

This code will extract most useful fields from Event class( ID, START, END, SUBJECT, BODY, ATTENDEES, ORGANIZER, ONLINE_MEETING) for more customization check the Event class from com.microsoft.graph.models;

Also we used convertToLocalDateTime() method because event.getStart() and event.getEnd() are using DateTimeTimeZone class from com.microsoft.graph.models and in Java LocalDateTime is a common practice for handling date and time information because it provides a simple, flexible, and timezone-agnostic way to work with temporal data.

Create Outlook Calendar event

You can programmatically create calendar events, set their properties, and handle errors gracefully. The following method will create simple Outlook Calendar event.

• add code below to your OutlookService

You can extend the event creation logic to include additional properties. This feature is particularly useful for applications that require automated scheduling, such as booking systems, appointment schedulers, or collaboration tools. With the power of Microsoft Graph API, you can build robust and user-friendly calendar integrations.

Conclusion

By following this guide, you can integrate Microsoft Outlook Calendar into your Java application and provide powerful scheduling features to your users. For more advanced use cases, explore the Microsoft Graph API documentation.