The MyTimetable Office 365 integration is able to connect to a user's calendar using the Outlook Calendar REST API. This page describes how to grant MyTimetable access to the Outlook Calendar REST API. MyTimetable will then be able to access calendars without explicit consent of a user.
Setting up a new Azure AD application
Please follow the following steps to set up the Azure AD application.
Step 1: Registering MyTimetable as an application in Azure AD
First, we need to register a new app in Azure AD, using the Microsoft Azure Management Portal.
- Visit the Microsoft Azure Management Portal at portal.azure.com, using the credential of your Microsoft tenant that has the subscription to Office 365 you wish to use.
- Go to "Azure Activity Directory".
- In the menu, click "App registrations".
- Click "New registration".
- Enter the Name of the application (e.g. MyTimetable-prod).
- Select 'Accounts in this organizational directory only' as we currently only support single tenant apps.
- Enter
https://<your-mytimetable-site>/schedule?zoneview=0&ec_type=o365as Redirect URI, replacing<your-mytimetable-site>with the appropriate value. - Click "Register".
- Copy the Application (client) ID of the registered app, so you can provide it to the Eveoh support department (see Information required for MyTimetable configuration).
Your application is now registered with Azure AD. Proceed with the next step to specify the app permissions.
Step 2: Specifying app permissions
Next, we need to make sure the newly created app has the correct permissions to access user calendars.
The "Read and write calendars in all mailboxes" application permission is described by Microsoft as "Allows the app to create, read, update, and delete events of all calendars without a signed-in user". Less restrictive scopes that allow MyTimetable to perform the operations required are not available at the moment. MyTimetable only reads, updates and deletes calendar events it has created itself, but this is something that is enforced in the synchronisation backend, not by Office 365. So while MyTimetable does not read, update or delete other calendar events, it does have the permissions to do so.
When using application-level permissions, this permission can optionally be scoped to specific mailboxes by following the instructions at Scoping application permissions to specific Exchange Online mailboxes.
- In the newly created application choose "API permissions".
- Click "Add a permission".
- When using application-level permissions (e.g., MyTimetable is authorised to sync to all mailboxes by default):
- Choose "Microsoft Graph" > "Application Permissions" > "Calendars" and tick "Calendars.ReadWrite".
- Click "Add permissions".
- Add another permission (required for older MTT versions), click "Add a permission" again.
- Choose "Exchange" > "Application Permission" > "Calendars" and tick "Calendars.ReadWrite.All".
- Click "Add permissions".
- Click "Select"
- Click "Done"
- When using delegated-level permissions (e.g., the user still has to authorise MyTimetable itself when enabling the sync):
- Choose "Microsoft Graph" > "Delegated Permissions" > "OpenId permissions" and tick "offline_access".
- Also choose "Calendars" and tick "Calendars.ReadWrite".
- Click "Add permissions".
- Click "Select"
- Click "Done"
- Click "User.Read"
- Click the "Remove permissions" button and confirm using "Yes, remove"
When using application-level permissions, we need to consent to the apps permissions on behalf of all users in the tenant. This step is not required for delegated-level permissions:
- Click the "Grant admin consent" button and confirm using "Yes"
Step 3: Generating and uploading a X.509 certificate
- If you are using MyTimetable managed hosting, Eveoh will provide you with a certificate to upload. If you are an on-premises customer you will need to create this certificate yourself by following:
- We need to create a self-signed certificate. This can be done using the minimal openssl install found at https://files.eveoh.nl/openssl_min.zip (for Windows) or an OpenSSL install included in the OS (Linux). From the command line, create a self-signed certificate and enter a password (make sure to remember this), the university name, country and domain name of your MyTimetable instance (common name):
openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 3650 -config openssl.cnf
- Back in the Azure Management Portal, click "Certificates & secrets".
- Choose "Upload certificate".
- Upload the "cert.pem" file from Eveoh or generated in the first step.
- Click "Add"
- The key should now be visible under "Public Keys".
Information required for MyTimetable configuration
In order to enable service calls to the Outlook Calendar REST API, the Eveoh support department requires the following information:
- Azure AD tenant name
- Application (client) ID of the registered app
- For on-premises hosting:
- Public key of the X.509 certificate (cert.pem)
- Private key of the X.509 certificate (key.pem)
- Password for the private key
Storing the X.509 certificate and private key in a Java Keystore (optional)
MyTimetable requires the generated X.509 certificate and the corresponding private key to be available in a Java Keystore. The Eveoh support department can store the X.509 certificate and its private key into a Java Keystore for you. If you want to do it yourself, please follow these steps:
- Save the X.509 certificate and the private key into the PKCS12 format using OpenSSL:
openssl pkcs12 -export -in cert.pem -inkey key.pem -out cert.pfx
- Convert the PKCS12 format into a JKS file, using keytool (available in the JRE/JDK):
keytool -importkeystore -srckeystore cert.pfx -srcstoretype pkcs12 -destkeystore cert.jks -deststoretype JKS
Certificate rollover
It is possible to configure multiple X.509 certificates for the application, for example for rollover scenarios in case a certificate expires.
- Follow the steps as specified at Generating and uploading a X.509 certificate.
- Securely send the new private key and certificate to Eveoh, including the password for the private key.
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