Microservices In Practice: Developing Instagram Clone —Auth Service

This is part 3 of Developing Instagram Clone series, other parts are linked below

1. Developing Instagram Clone: Introduction.
2. Developing Instagram Clone: Discovery Service.
3. Developing Instagram Clone: Auth Service
4. Developing Instagram Clone: Media Service.
5. Developing Instagram Clone: Post Service.
6. Developing Instagram Clone: Graph Service.
7. Developing Instagram Clone: Newsfeed Service.
8. Developing Instagram Clone: Gateway Service.
9. Developing Instagram Clone: Front-end Service

Token based authentication

In Monolithic applications, a user provides username and password, the security module validates user credentials and create a session for the user. A session Id is returned to the client and the client stores the session Id in cookies and send it with each request as an identifier for the user.

This approach making the service statefull has an impact on the scalability because a session should be stored for each user, the more users you’ll have the more memory you’ll need.