Custom error page for AssetsBundle

[Zinurist]

Custom error page for AssetsBundle

[Zinurist]

My solution for now is to inherit AssetsBundle and implement the previous behavior (kotlin code):

class SPAAssetsBundle(resourcePath: String, uriPath: String, indexFile: String, assetsName: String) :
	AssetsBundle(resourcePath, uriPath, indexFile, assetsName) {
	override fun createServlet(): AssetServlet {
		return SPAAssetServlet(resourcePath, uriPath, indexFile, defaultMediaType, StandardCharsets.UTF_8)
	}
}

class SPAAssetServlet(resourcePath: String, uriPath: String, indexFile: String?, defaultMediaType: String?, defaultCharset: Charset?) :
	AssetServlet(resourcePath, uriPath, indexFile, defaultMediaType, defaultCharset) {
	override fun doGet(req: HttpServletRequest, resp: HttpServletResponse) {
		super.doGet(req, resp)
		if (resp.status == HttpServletResponse.SC_NOT_FOUND) {
			resp.sendError(HttpServletResponse.SC_NOT_FOUND)
			// or do something else...
		}
	}
}

Would also allow for more complex error handling.

[zUniQueX]

Hi @Zinurist. The problem of using sendError instead of setStatus is that not catching exceptions like IOException would lead to information exposure through the servlet container's error page mechanism. Therefore we decided to use setStatus to keep Dropwizard safe in the default configuration.

If you want to use custom error pages through the container's error page mechanism, you can restore the previous behaviour yourself. setStatus doesn't commit the response, so you can modify it afterwards. The following code snippet provides a very simple Filter that resets the response and uses sendError to trigger the error pages:

environment.servlets().addFilter("sendError", new Filter() {
            @Override
            public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
                filterChain.doFilter(servletRequest, servletResponse);
                if (!(servletResponse instanceof HttpServletResponse)) {
                    throw new IllegalStateException("Expecting instance of HttpServletResponse");
                }
                HttpServletResponse httpServletResponse = (HttpServletResponse) servletResponse;
                int status = httpServletResponse.getStatus();
                if (!httpServletResponse.isCommitted() && httpServletResponse.getStatus() >= 400) {
                    httpServletResponse.reset();
                    httpServletResponse.sendError(status);
                }
            }
        }).addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST), true, "/*");

[Zinurist]

Thank you for the help! Closing the issue since I was able to work around it.