title: How get a token in spring boot 2 oauth2?
body: <p>I'm new in spring security oauth2. I want to run this <a href="https://github.com/talk2amareswaran/spring-boot2-oauth2-auth-server-jwt-mysql" rel="noreferrer">authorization server sample code</a>. I run it successfuly, for get token, I set postman as follow and then send request:</p>
  
  <p><a href="https://i.stack.imgur.com/eRg7t.png" rel="noreferrer"><img src="https://i.stack.imgur.com/eRg7t.png" alt="Basic Auth"></a>
  <a href="https://i.stack.imgur.com/hUtdn.png" rel="noreferrer"><img src="https://i.stack.imgur.com/hUtdn.png" alt="grant types"></a></p>
  
  <p>In this case, I entered client id with its password, but I want to login without them. For example my users send username, password and client id and then get token. But every request I send, The server return 401 response. In <a href="https://docs.spring.io/spring-boot/docs/2.1.3.RELEASE/reference/htmlsingle/" rel="noreferrer">Spring boot 2</a> oauth 2, <strong>How can I do it?</strong></p>