We were using angular v1 in my previous job. For authentication we used to store JWT in cookies docs.angularjs.org/api/ngCookies/service/$cookies and used httpInterceptors docs.angularjs.org/api/ng/service/$http we can able to intercept requests before they are handed to the server and responses before they are handed over to the application code that initiated these requests.
interceptors are used to inject jwt token in every request for authorization.