Spring Security, Webjars, and MIME type error
I volunteered to be JLO (Java Language Owner) at CircleCI and I am currently working on getting a sample Spring Framework project running on CircleCI 2.0. I made a simple app bootstrapped with the Spring Initializer. I included Spring Security for the first time and I decided to try out WebJars for static Javascript libraries such as bootstrap. I am using Thymeleaf for templating.The app does not actually do anything yet but I ran into a pretty strange issue today that I wanted to write up here. My home page is pretty straightforward.
<!DOCTYPE html> <html xmlns:th="https://www.thymeleaf.org"> <head> <title>CircleCI Spring Demo</title> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><span class="p"><</span><span class="nt">link</span> <span class="na">rel</span><span class="o">=</span><span class="s">"stylesheet"</span> <span class="na">th:href</span><span class="o">=</span><span class="s">"@{/webjars/bootstrap/3.3.7/css/bootstrap.min.css}"</span> <span class="p">/></span> <span class="p"><</span><span class="nt">link</span> <span class="na">rel</span><span class="o">=</span><span class="s">"stylesheet"</span> <span class="na">th:href</span><span class="o">=</span><span class="s">"@{/css/style.css}"</span> <span class="na">href</span><span class="o">=</span><span class="s">"../static/css/style.css"</span> <span class="p">/></span></head> <body>
<span class="p"><</span><span class="nt">nav</span> <span class="na">class</span><span class="o">=</span><span class="s">"navbar"</span><span class="p">></span> <span class="p"><</span><span class="nt">div</span> <span class="na">class</span><span class="o">=</span><span class="s">"container"</span><span class="p">></span> <span class="p"><</span><span class="nt">div</span> <span class="na">class</span><span class="o">=</span><span class="s">"navbar-header"</span><span class="p">></span> <span class="p"><</span><span class="nt">a</span> <span class="na">class</span><span class="o">=</span><span class="s">"navbar-brand"</span> <span class="na">href</span><span class="o">=</span><span class="s">"#"</span><span class="p">></span>CircleCI Demo Spring<span class="p"></</span><span class="nt">a</span><span class="p">></span> <span class="p"></</span><span class="nt">div</span><span class="p">></span> <span class="p"><</span><span class="nt">div</span> <span class="na">id</span><span class="o">=</span><span class="s">"navbar"</span> <span class="na">class</span><span class="o">=</span><span class="s">"collapse navbar-collapse"</span><span class="p">></span> <span class="p"><</span><span class="nt">ul</span> <span class="na">class</span><span class="o">=</span><span class="s">"nav navbar-nav"</span><span class="p">></span> <span class="p"><</span><span class="nt">li</span> <span class="na">class</span><span class="o">=</span><span class="s">"active"</span><span class="p">><</span><span class="nt">a</span> <span class="na">href</span><span class="o">=</span><span class="s">"#"</span><span class="p">></span>Home<span class="p"></</span><span class="nt">a</span><span class="p">></</span><span class="nt">li</span><span class="p">></span> <span class="p"><</span><span class="nt">li</span><span class="p">><</span><span class="nt">a</span> <span class="na">href</span><span class="o">=</span><span class="s">"#"</span><span class="p">></span>About<span class="p"></</span><span class="nt">a</span><span class="p">></</span><span class="nt">li</span><span class="p">></span> <span class="p"></</span><span class="nt">ul</span><span class="p">></span> <span class="p"></</span><span class="nt">div</span><span class="p">></span> <span class="p"></</span><span class="nt">div</span><span class="p">></span> <span class="p"></</span><span class="nt">nav</span><span class="p">></span> <span class="p"><</span><span class="nt">div</span> <span class="na">class</span><span class="o">=</span><span class="s">"container"</span><span class="p">></span> <span class="p"><</span><span class="nt">h1</span><span class="p">></span> CircleCI Spring Demo <span class="p"></</span><span class="nt">h1</span><span class="p">></span> <span class="p"></</span><span class="nt">div</span><span class="p">></span> <span class="p"><</span><span class="nt">script</span> <span class="na">th:src</span><span class="o">=</span><span class="s">"@{/webjars/bootstrap/3.3.7/js/bootstrap.min.js}"</span><span class="p">></</span><span class="nt">script</span><span class="p">></span></body> </html>
mvn spring-boot:run none of the styles showed up and console showed the following error message:Resource interpreted as Stylesheet but transferred with MIME type text/html
login.html) instead of serving up the stylesheet from the/webjars directory. The solution is to update my security configuration to whitelist anything that comes from /webjarspackage com.circleci.demojavaspring;import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.annotation.Configuration; import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder; import org.springframework.security.config.annotation.web.builders.HttpSecurity; import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter; import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
@Configuration @EnableWebSecurity public class WebSecurityConfig extends WebSecurityConfigurerAdapter { @Override protected void configure(HttpSecurity http) throws Exception { http .authorizeRequests() .antMatchers("/", "/home", "/webjars/**").permitAll() .anyRequest().authenticated() .and() .formLogin() .loginPage("/login") .permitAll() .and() .logout() .permitAll(); } }
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