Dropwizard : New admin resource

Question

I\'m using Drowpizard 0.7.1, but perhaps I will upgrade to 0.8.4 very soon.

Does anyone know how to add a admin resource to dropwizard, that is shown in Operational Menu

Answer 1

Using .addMapping("") with Dropwizard version 0.9.1 allows you to override the menu without conflicting with the default AdminServlet mapping at "/*".

In the Application:

public void run(final NetworkModelApplicationConfiguration configuration, final Environment environment) {
    environment.admin().addServlet("my-admin-menu", new MyAdminServlet()).addMapping("");
    environment.admin().addServlet("my-admin-feature", new MyAdminFeatureServlet()).addMapping("/myAdminFeature");
}

Extending AdminServlet isn't very useful since all the properties are private. I built an HTTPServlet that reads a resource as a template:

public class MyAdminServlet extends HttpServlet {
  private String serviceName;

  @Override
  public void init(ServletConfig config) throws ServletException {
    super.init(config);
    this.serviceName = config.getInitParameter("service-name");
  }

  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    String path = req.getContextPath() + req.getServletPath();
    resp.setStatus(200);
    resp.setHeader("Cache-Control", "must-revalidate,no-cache,no-store");
    resp.setContentType("text/html");
    PrintWriter writer = resp.getWriter();

    try {
      String template = getResourceAsString("/admin.html", "UTF-8");
      String serviceName = this.serviceName == null?"":" (" + this.serviceName + ")";

      writer.println(MessageFormat.format(template, new Object[] { path, serviceName }));
    } finally {
      writer.close();
    }
  }

  String getResourceAsString(String resource, String charSet) throws IOException {
    InputStream in = this.getClass().getResourceAsStream(resource);
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    byte[] buffer = new byte[1024];
    int len;
    while ((len = in.read(buffer)) != -1) {
      out.write(buffer, 0, len);
    }
    return out.toString(charSet);
  }
}

My /admin.html resource looks like this:

  
    
    
  
  
    
Operational Menu{1}
    

      
Metrics
      
Ping
      
Threads
      
Healthcheck
      
My Admin Feature