title: Flutter with REST backend Springboot
body: <p>I am developing a <strong>Flutter mobile application</strong> with a <strong>Spring Boot backend</strong>. I want to have three types of login methods <strong>(1)</strong>. username &amp; password <strong>(2)</strong>. Facebook <strong>(3)</strong>. Google.</p>
  
  <p><strong>I have following questions</strong>.</p>
  
  <p><strong>1)</strong> If I handle the Authentication part in the mobile App via Firebase Authentication (And store all the user on Firebase), do I need to write authentication code on my <strong>Spring Boot</strong> side? Or I need to keep my authentication on the Sprin Bboot side only?</p>
  
  <p><strong>2)</strong> I want the JWT token for all the authentication system (Facebook, Google and username &amp; password). The mobile app will send the JWT token for every requests it make to the Springboot app.</p>
  
  <p><strong>3)</strong> I am looking for a step by step tutorial that shows how can I integrate all these login methods in my Springboot REST APIs. I have looked many but all they have some different different methods or dependencies. Like some are adding <strong>Facebook</strong> dependency in the maven and some only add the <strong>Oauth2</strong>.</p>
  
  <p>Thanking you in advance</p>