But isn't this why the property exists on the filter - to override it in one place if you don't like the default?

You can override it, but I don't think we should have the default be a property that users feel like they have to override because the name is so verbose and annoying to use =) I think the default should be nice and simple, and we should have our simple webapp example use that property. If the user wants to override it for some reason, or in the rare case (probably never) that it conflicts with some other request attribute, they can easily override it.

My 2 cents...


On Mon, Apr 6, 2009 at 1:26 PM, Jeremy Haile <[email protected]> wrote: I understand why you did this - it's a cleaner namespace, etc. but it makes it a pain in the butt to reference in code. I'm trying to find a shorter attribute that is still relatively safe but isn't so dang long.

As to why it would be used in a JSP - see my simple example earlier in this thread.


On Apr 6, 2009, at 1:16 PM, Les Hazlewood wrote:

To further explain my thoughts: by having a prefix 'ki.', instead of just 'ki', I'm being explicit that the attribute is something ki set, whereas 'kiAuthenticationException' might imply that the exception is an AuthenticationException concrete subclass instance in the API. But, because end-users can subclass the exception hierarchy, it might not be a ki exception directly. It could also be an application-specific exception.

A very minor distinction, sure, but that was my reasoning at least.

On Mon, Apr 6, 2009 at 1:09 PM, Les Hazlewood <[email protected]> wrote: Because its not the AuthenticationException itself - just the class name.

Just 'kiLoginException" would imply the following would be possible:

AuthenticationException exception = (AuthenticationException)request.getAttribute("kiLoginException");

which is not the case.

Just out of curiosity, why would a JSP reference this value? And even if they did, isn't that the purpose of the setter method to override the default in case the end-user didn't like to type that?


On Mon, Apr 6, 2009 at 1:03 PM, Jeremy Haile <[email protected]> wrote: Oops - accidentally replied to an incorrect thread. Meant to post here:

What about kiLoginException? I like short and sweet since this will likely be referenced directly from JSPs


On Apr 6, 2009, at 12:57 PM, Les Hazlewood wrote:

P.S. That was my best initial solution to the problem - by storing a fully qualified exception name of the failure exception. Maybe that's good enough, but if there is a more elegant solution, I'm all ears!

On Mon, Apr 6, 2009 at 12:52 PM, Kalle Korhonen <[email protected] > wrote: Thanks Jeremy, that's exactly what I was after. With that info I don't need to re-try the login.

Kalle



On Mon, Apr 6, 2009 at 9:38 AM, Jeremy Haile <[email protected]> wrote: If you are using the FormAuthenticationFilter (the default), you can also put some logic in your view layer to display the error message. Ki automatically adds the fully qualified class name of the exception that was thrown as a request attribute that you can key off of. The request attribute is based on the "failureKeyAttribute" property of the filter, so you can adjust in your ini by setting "authc.failureKeyAttribute=myAttribute" The default attribute name is "jsecLoginFailure".

By default it is set to the fully qualified classname of the exception that was thrown during authentication. This would allow you to do something like (simple JSP example):

<c:if test="${jsecLoginFailure eq 'org.jsecurity.authc.IncorrectCredentialsException'}">
  <span class="errors">The password you entered is incorrect.</span>
</c:if>

To do something more custom when authentication fails (but still using the built-in filter), you could always extend FormAuthenticationFilter and override the setFailureAttribute(...) method or onLoginFailure(...) method.

Jeremy


On Apr 6, 2009, at 12:23 PM, Kalle Korhonen wrote:

(Had accidentally sent to dev list, moving to user list).

On Mon, Apr 6, 2009 at 6:07 AM, Jeremy Haile <[email protected]> wrote: How authentication failures are displayed to the user is generally application specific. Usually applications catch AuthenticationException or some of its subclasses if more granular reporting is required. They then translate those exceptions into a validation message and display it to the user. Also, for security reasons, it's generally not a good idea to tell the user whether they entered a non-existant username or an incorrect password.

Thanks for reply, Jeremy. Yes, that's obvious.

The simplest example may look like this:
       try {
           subject.login(...);
       } catch (AuthenticationException e) {
// Add something to the request to communicate the login failure to the user
       }
You could add additional catch blocks above the AuthenticationException to catch different subclass exceptions and give more specific error messages.

Exactly - that's what I meant when I said "handle login myself". Exception handling is straight-forwarded in this case. If it wasn't clear from my previous example, the question was: "How does the application obtain the failure reason if Ki filtered is configured to run before the application filters and handles the authentication"? From what I gathered, the answer is either "not meant to do so" or "up to you to implement", in which case an exception specific error-page may be the best solution.

To obtain the originally requested URL from Ki, call WebUtils.getSavedRequest(...) which will give you back a SavedRequest object describing the original request. This can be used to redirect after login. If you do not want Ki to do the authentication for you, but would rather execute it in your web framework, you can change the "authc" filter to pass-thru requests to your web framework. In this case, Ki assumes that you will handle the authentication yourself which sounds like the behavior you are after. To get this to work, add the

Ah, missed WebUtils. Yeah, if you read my description again, you'll see that I'd rather not handle the login myself but in that case the problem is how do I let the application know in that case why the authentication failed. It's not simply a choice between filter handling authentication or the application handling it. If it's handled in the application, the request may needs to pass through several other filters, but if it's its handled in the authentication filter the control has not yet been passed to the lower layers. Sounds like my solution (let framework handle the success case, but allow failure case to go through to the application layer) has some advantages.

Kalle



On Apr 6, 2009, at 2:04 AM, Kalle Korhonen wrote:

Is there a standard/recommend way in JSecurity/Ki to make the reason for an authentication failure available to the application? Similarly to CMA, if Ki is configured to run before the application servlet/filter, there's no direct way to tell the application why an authentication try failed. Is the
recommended mechanism in this case to try to use a standard
"<error-page><exception-type>" element in web.xml or something else? The other way around, if I create a login form and handle the authentication in it myself (by calling SecurityUtils.getSubject().login() ) is there a way to obtain the "originally requested url" from Ki that the security filter
intercepted, then redirected to login page?

Currently I implemented this so that a login form that *could* handle login, but a success case is directly handled by Ki. In a failure case, Ki let's the request through and I just re-try the authentication to get the failure
reason. This is a little hackish and results in an unnecessary
authentication try in a failure case, but works surprisingly well for me as
it allows me to use the "native" error message mechanisms of my web
application framework.

Kalle












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