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 /webjars
package 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(); } }
Thank you for reading! Share your thoughts with me on bluesky, mastodon, or via email.
Check out some more stuff to read down below.
Most popular posts this month
- 2024
- Reinstalling Windows at 1am
- SQLite DB Migrations with PRAGMA user_version
- My Custom Miniflux CSS Theme
- How to Disable Wayland in Debian Testing
Recent Favorite Blog Posts
This is a collection of the last 8 posts that I bookmarked.
- Future Fonts from Blog – Brad Frost
- 21st Century C++ from Communications of the ACM
- Submarines DevCon 2025 Keynote Speech from JoshHaines.com
- How I Use AI: Meet My Promptly Hired Model Intern from Armin Ronacher's Thoughts and Writings
- DeepSeek from Maggie Appleton
- Digital Reality Digital Shock from Christopher Butler
- 10 habits to help becoming a Debian Maintainer from Optimized by Otto
- Tiny corners from Manuel Moreale RSS Feed
Articles from blogs I follow around the net
MusicBrainz Picard identifies songs from *.mp3 files and automatically fixes metadata
In my first attempt to switch from streaming to move back to listening to *.mp3 files, one of the issues I encountered was organization: how to standardize the metadata of the songs? The solution I was familiar with at the time — manually editing each son…
via Manual do Usuário April 24, 2025Google's control of the web could be coming to an end
It's been hard to avoid the US government's antitrust case against Meta lately, since CEO Mark Zuckerberg spent three days in front of the cameras in Congress, testifying about his company's alleged anti-competitive tactics. But another equall…
via The Torment Nexus April 24, 2025$5 million in tokens stolen from ZKsync
An attacker compromised an admin account belonging to the ZKsync Ethereum layer-2 project, which is built by Matter Labs. By doing so, they were able to steal approximately $5 million worth of the ZK token, which the project said wer…
via Web3 is Going Just Great April 24, 2025Generated by openring