Sending teams messages without setting up an Office 365 connector requires an authenticated user to send the messages. This user (or users) is stored in a Teams Messaging Account in FlexDeploy which can be managed at Topology->Integrations->Messaging.
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Follow these steps to create the app registration:
Sign in to the Azure portal
If you have access to multiple tenants, use the directory + subscription filter in the top menu to select the tenant in which you want to register an application.
Search for and select Azure active directory.
Under Manage, select app registrations, then new registration.
Enter a Name for your application and specify who can use the application.
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Select register to complete the initial app registration.
Open application capture application (client) ID and directory (tenant) ID from app registration.
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Create a new client secret and capture client secret.
Info title Note Record the secret's value for use in your client application code - it's never displayed again after you leave this page.
Create API permissions
Select API permissions > Add a permission > Microsoft Graph
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Select delegated permissions. You can type the names of these permissions in to filter and find the necessary permissions quickly. The 7 or 8 permissions you need are:
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The following image shows the minimum permissions required to send messages to teams and users.
After adding them all, click the Grant admin consent button. You should see checkmarks Granted by An Administrator next to each permission in the status Granted through column.
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Setting up Certificates
You may need to install the certificate for https://graph.microsoft.com/.default into your Java keystore. If this is the case, you will get an error about building a certificate path.
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All Microsoft Teams versions are supported.
Key Features
Send messages to a Microsoft Teams channel or user.