Enabling Spring Security makes Swagger output text/plain instead of HTML

Swagger works! I can interact with http://localhost:8090/sdoc.jsp and everything is fine.

I add the following to pom.xml...

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-security</artifactId>
</dependency>

I also add the following two files:

@Component
public class CustomAuthenticationProvider implements AuthenticationProvider {
    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
        String name = authentication.getName();
        String password = authentication.getCredentials().toString();

        if( !Authenticate.authenticate(name, password) )
            return null;

        List<GrantedAuthority> grantedAuths = new ArrayList<>();
        grantedAuths.add(new SimpleGrantedAuthority("ROLE_USER"));
        Authentication auth = new UsernamePasswordAuthenticationToken(name, password, grantedAuths);
        return auth;
    }

    @Override
    public boolean supports(Class<?> authentication) {
        return authentication.equals(UsernamePasswordAuthenticationToken.class);
    }
}

and

@Configuration
@EnableWebMvcSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            .csrf()
                .disable()

            .authorizeRequests()
                .anyRequest().permitAll()
                .antMatchers("/**").authenticated().and()
                .formLogin().loginPage("/login").permitAll().and()
                .httpBasic()
                ;
    }

    @Autowired
    public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
        auth.authenticationProvider(new CustomAuthenticationProvider());
    }
}

At this point if I visit the same URL that was previously working I now instead get a response type of "text/plain" and instead of a pretty HTML looking browser I see source code.

If I revert the change and remove the two files from project and remove JAR file it works again.

How do I get Spring Security and Swagger to play nice? What am I doing wrong.

I suspect this is due to Spring-Security's effect on the content-type headers (http://docs.spring.io/spring-security/site/docs/3.2.0.CI-SNAPSHOT/reference/html/headers.html#headers-content-type-options).

From the docs -

Historically browsers, including Internet Explorer, would try to guess the content type of a request using content sniffing. This allowed browsers to improve the user experience by guessing the content type on resources that had not specified the content type. For example, if a browser encountered a JavaScript file that did not have the content type specified, it would be able to guess the content type and then execute it.

The problem with content sniffing is that this allowed malicious users to use polyglots (i.e. a file that is valid as multiple content types) to execute XSS attacks. For example, some sites may allow users to submit a valid postscript document to a website and view it. A malicious user might create a postscript document that is also a valid JavaScript file and execute a XSS attack with it.

Again, from the docs, in order to override the default -

@EnableWebSecurity
@Configuration
public class WebSecurityConfig extends
   WebSecurityConfigurerAdapter {

  @Override
  protected void configure(HttpSecurity http) throws Exception {
    http
      // ...
      .headers()
        .contentTypeOptions();
  }
}