In many of the SaaS web applications (ex, Atlassian JIRA), a user can have dedicated subdomain. For example, if my user name is helloworld, then after I log in to the web application, I am redirected to helloworld.atlassian.net
How to implement this in Spring Framework？
Do I have to have one application server instance running for each customer? But this dosent seem to be the cheapest solution. Does Spring have such feature that I can create dynamic subdomain based on the username, and in the backend, only one instance of application server is running?
Create a custom filter which parses whole url and extracts subdomain, then check if the user is on proper domain with proper rights. Also worth mentioning Nginx should redirect "*.yourdomain.com" so all subdomains don't have to exist in Nginx, they could exist in database and each user has his unique or can be multiple sudomains attached, your custom filter does the checking on each request.