We have site provisioning process which created SharePoint online sites. Provisioning works just fine. My question is - is it possible to include few extra tasks to site provisioning or right after it?
This is what I want to achieve:
1) the request access is set by default firstname.lastname@example.org. I liked to change this automatically
2) Also I liked to add a new app to the site - it is just another document library
3) and finally I liked to change the metadata of sitepages library site called metadata.aspx
I don't need quidance how to do this, just opinion is this possible to automate is enough. But if you like to tell how, that is totally up to you :)
This is absolutely possible and quite common scenario. This is exactly what the remote provisioning patterns introduced in SharePoint Patterns and Practices are doing either using code (self-service) or by using PnP PowerShell (admin driven).
Typical process is that you provision oob team site / oob publishign site and then you apply the needed modifications on top of the oob site by using remote APIs. These could include all of the setting what you have mentioned, since those are exposed with SharePoint Online CSOM - it's just matter of calling the needed code / script after site provisioning.