Creating The Admin Page

Before we can create a contest, we need to create the Admin page. This is where the site administrator can do things that only site administrators can do. Right now that's only creating a contest, but later on we'll have a variety of admin only tasks.

Again, because I'm not a web designer, this page is going to be only a page of links to the admin only pages. I will add on some extra security...not only does someone have to be logged on to see this page, but they have to also be a site administrator.

I'll start with the web template. Here's what will go between the body and /body tags in my new siteAdmin.ftl:


<h1>Site Administration Options</h1>

<#include "navigation.ftl">

<a href="/newContest">Create A Contest</a>


I also need a template for when they don't have enough permission to view the page. I already have one for when they're not logged in. Rather than create a template for each possible error condition when the only difference in those conditions is the text displayed, I'll do some refactoring here and create an error.ftl template.

This will be similar to profileNotLoggedIn.ftl, except I'll put ${heading} between the h1 and /h1 tags, and modify ProfileServlet.java to pass in "User Profile" in the data model as the heading when they're not logged in. I'll also replace the "not logged in" text with ${errorMessage} and modify ProfileServlet.java to add that to the data model with the not logged in message. ProfileServlet.java will also be modified to use error.ftl instead of profileNotLoggedIn.ftl.

Okay, back to creating AdminServlet.java. I'll use ProfileServlet.java as a basis, since it does something similar. I'll change the successful template to siteAdmin.ftl, the error message to "You do not have permissions to view this page", and the heading to "Site Administration Options".

I'll also remove the bits that check for the submit button and update the user name, since those are profile specific. Along with that, I can get rid of the message field from the data model.

The last modification is to require that they not only be logged in, but that they actually be site administrators. The bits inside the try block should now read:


List<User> results = (List<User>) query.execute(userid);
User user = results.get(0);

Integer userLevel = user.getUserLevel ();
String name = user.getName ();
root.put("userLevel", userLevel);
root.put("name", name);
root.put("heading", "Site Admistration Options");

if (userLevel > 0)
{
template = "siteAdmin.ftl";
}


I then need to change the error handling a bit, so that the error template is shown no matter what went wrong. I'll take the else out, and replace it with:


if (template.equals("error.ftl"))


That way, the error template displays if the user wasn't logged in, if they aren't a site administrator, or if something weird happened with fetching from the data store.

Because the user might be logged in, I also need to take the root.put("loggedIn", false) in that error block, and move it to just after declaring the root variable. Then, under the if (session != null) line, I'll use root.put("loggedIn", true) to change it to true. This ensures that the navigation.ftl has the loggedIn variable set correctly for displaying the right navigation bar.

I'll also go back and make that same else change in ProfileServlet, since it's more robust.

Oh, and I also need to modify web.xml to use AdminServlet for calls to /admin. Note that the only way to test the error handling in the admin panel is to manually type in the URL for the admin panel into the browser. If our navigation template is working correctly, we won't see links to the admin section.

I left some of the code changes deliberately vague. You should be able to follow what needs to be done, and experimenting to get it right will help you figure out how everything fits together.

All of that was just to get our page for the admin options. We still need to create the page for making a new contest.