Web application on tomcat sending response as text/html instead of text/css as request is for css loading & page not loading properly

Question

I have put static files outside of war file(Not in Apache2) and accessing by putting context entry in server.xml file & all in ubuntu environment(VM) Like below:

<Context path="/my_app" docBase="my_app.war"> 
            <Resources className="org.apache.catalina.webresources.StandardRoot">
              <PostResources className="org.apache.catalina.webresources.DirResourceSet"
                                 base="/opt/tomcat/datacom/virtualwebserver/"
                                 webAppMount="/">
              </PostResources>
            </Resources>
 </Context>

Note:Tomcat web.xml has a mime-type entry for text/CSS already

My Web Application web.xml contains below entries:

<welcome-file-list>

        <welcome-file>/jsp/login/welcome.jsp</welcome-file>

    </welcome-file-list>
    <mime-mapping>
        <extension>js</extension>
        <mime-type>application/javascript</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>css</extension>
        <mime-type>text/css</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jpg</extension>
        <mime-type>image/jpeg</mime-type>
    </mime-mapping>

    <filter>
        <filter-name>requestLog</filter-name>
        <filter-class>com.dci.db4.filter.RequestLog</filter-class>
    </filter>

    <filter>
      <filter-name>struts2</filter-name>
       <filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>
    </filter>

Answer 1

Upgradation of tomcat version may raise this type of problem. version 8.5.37 and 9.0.14 seems to serve CSS files embedded in web app as content-type : text/html; charset=UTF-8 instead of content-type : text/css; charset=UTF-8. This cause the browser not to interpret the CSS.

To solve this problem, try to relocate your .css files inside /css directory of web app and load them from there.

Hope this will work for you.

Answer 2

I had a very similar problem. We upgraded Tomcat version and after that content-type was equal to text/html;charset=UTF-8 for whatever resources I tried to retrieve from the server. Firstly I thought that there is some problem with DefaultServlet and MIME mapping configurations. But it turned out that starting from tomcat version 8.5.36

The default Servlet should not override a previously set content-type.

https://oraweb.slac.stanford.edu/docs/changelog.html

And there was the following filter in our application that was applied to all endpoints:

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        // Setting the character set for the request
        request.setCharacterEncoding("UTF-8");

        // Setting the character set for the response
        response.setContentType("text/html; charset=UTF-8");

        // pass the request on
        chain.doFilter(request, response);
    }

Therefore tomcat couldn't override content-type