SharePoint Alerts notifications customized

Hello, Victor!

There is no OOTB solution for notifications with customization at all, not only in SPO. In SharePoint On-Prem we can change the templates, but it is very hard and it is not supported by the vendor. In this case, almost every SharePoint developer has own solution for this situation. Someone uses workflow of custom solution for his case. We developed such kind of solution that can cover almost all standard alerts functions and it works like this:

1. The solution has two interfaces. The first one is the console application, that you have to execute by schedule. You can store in on your own windows server and use windows tasks for it, or use something like Azure. The second one is the WebAPI service. And you also can store in on your own windows server and use windows tasks with powershell for it, or use something like Azure
2. The solution has a settings layer. After you install the solution (we use SPMeta2 for artefacts provision), there are some settings lists, like the list of SharePoint lists or libraries on which the custom alerts work, the list of templates with RichHTML control for each SharePoint list in previous list and the list of subscribers.
3. Some JavaScript code for applying notification for administrators in lists and users
4. So, the solution executes by schedule, finds the items which were updated for the last time in lists in settings, checks the permissions of the user in subscribers list if the item is published and sends the email for this user by the template from the templates list.

This solution can be extended for the needs of the client.