Confluence users can be exported to JSON format. You can read more about JSON here.
A Confluence user is as exported as JSON like below. The canUse property reflects the global Confluence permission Can use.
[ { "username": "tester", "active": true, "fullName": "tester", "email": "tester@mail.com", "directoryName": "Confluence Internal Directory", "createdDate": "2019-09-03 22:50", "updatedDate": "2019-09-19 09:20", "groups": [ "testing-space5", "confluence-users", "testing-space" ], "preferredLanguage": "Default", "canUse": true } ]