Configure JDBC Authentication in Spring Boot
<p>Goal:  Add jdbc authentication to spring boot with default security configurations.</p>

<p>Source can be found <a href="https://github.com/mosgjig/user" rel="nofollow">here</a></p>

<p>Per <a href="https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-security.html" rel="nofollow">Spring Boot Docs</a></p>

<blockquote>
  <p>configure the global AuthenticationManager by autowiring an AuthenticationManagerBuilder into a method in one of your @Configuration classes</p>
</blockquote>

<p>and <a href="http://docs.spring.io/spring-security/site/docs/4.0.3.RELEASE/reference/htmlsingle/#jc-authentication-jdbc" rel="nofollow">Spring Security Docs</a> with example:</p>

<pre><code>@Autowired
private DataSource dataSource;

@Autowired
public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
    auth
        .jdbcAuthentication()
            .dataSource(dataSource)
            .withDefaultSchema()
            .withUser("user").password("password").roles("USER").and()
            .withUser("admin").password("password").roles("USER", "ADMIN");
}
</code></pre>

<p>Given the above, added the following (<a href="https://github.com/mosgjig/user/blob/master/src/main/java/com/msyla/usergreeter/user/config/AuthenticationManagerConfig.java" rel="nofollow">found here</a>):</p>

<pre><code>@Configuration
@EnableAuthorizationServer
@EnableResourceServer
public class AuthenticationManagerConfig {

    @Autowired
    private DataSource dataSource;

    @Autowired
    public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
        auth.jdbcAuthentication()
                .dataSource(dataSource)
                .withDefaultSchema()
                .withUser("user").password("password").roles("ROLE_USER").and()
                .withUser("admin").password("password").roles("ROLE_USER", "ROLE_ADMIN");
    }
}
</code></pre>

<p>with resulting error:</p>

<pre><code>java.lang.IllegalStateException: Cannot apply org.springframework.security.config.annotation.authentication.configurers.provisioning.JdbcUserDetailsManagerConfigurer@13404f75 to already built object
</code></pre>

<p>and further up the logs, we can see the auto config doing it's thing when it shouldn't be:</p>

<pre><code>2016-02-02 22:52:48.047 DEBUG 30487 --- [ost-startStop-1] eGlobalAuthenticationAutowiredConfigurer : Eagerly initializing {org.springframework.boot.autoconfigure.security.SpringBootWebSecurityConfiguration=org.springframework.boot.autoconfigure.security.SpringBootWebSecurityConfiguration$$EnhancerBySpringCGLIB$$627430a8@78acaa86}
2016-02-02 22:52:48.074 DEBUG 30487 --- [ost-startStop-1] .s.BootGlobalAuthenticationConfiguration : Eagerly initializing {user=com.msyla.usergreeter.user.User$$EnhancerBySpringCGLIB$$3cd414fd@73128671, coreConfig=com.msyla.usergreeter.user.core.config.CoreConfig$$EnhancerBySpringCGLIB$$30c07250@6ed3c66b}
2016-02-02 22:52:48.095  INFO 30487 --- [ost-startStop-1] b.a.s.AuthenticationManagerConfiguration : 

Using default security password: 5b33158f-156d-43f4-892f-6c452f15e1cc
</code></pre>

<p>Question:  All that is being asked here is to have default boot configurations with the exception of where the user is being stored, jdbc instead of in memory. Am I doing it incorrectly?  Are the docs wrong?  I have tried several other routes to no avail.  </p>

<p>Thanks in advance!</p>