From Using Spring Security OAuth 2.0 and MongoDB For Single Sign Authentication Server I explained how I chose OAuth 2.0 and MongoDB to build a Single Sign On Auth server that can be used in a microservice architecture.
1. First step. Run sso-auth-client application. And try accessing http://localhost:8081/hello. Without passing any headers it returns this
2. Second step. Run sso-auth-server. Lets use the password grant_type to get an access token. http://localhost:8080/oauth/token?grant_type=password&username=user@awesome.com&password=cant_hack_this&client_id=sso-auth-client&client_secret=mySecret
3. Final step. Lets access http://localhost:8081/hello with our access token. And we are in.
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