Front-end login problem when following URL to External Login menu item

[eddiekonczal]

We're experiencing a front-end login problem:

If you are already logged into CAS on one Joomla! site via External Login, then enter the URL for an External Login front-end menu item in another browser window (as opposed to simply clicking on the menu item), you get this error:

Redirect Loop

Redirection limit for this URL exceeded. Unable to load the requested page. This may be caused by cookies that are blocked.

The browser has stopped trying to retrieve the requested item. The site is redirecting the request in a way that will never complete.

Have you disabled or blocked cookies required by this site?
NOTE: If accepting the site’s cookies does not resolve the problem, it is likely a server configuration issue and not your computer.

While clicking the actual menu item DOES work, this creates a problem for users who are trying to follow bookmarks or links from other pages to the front-end login URL.

Clearing cookies does resolve the problem but is problematic for users who need to manage multiple sites simultaneously.

[eddiekonczal]

I am not sure if this is a related issue, but External Login redirection only seems to work upon login; if you visit the login URL again, and redirection is set up, you get a redirect loop error.

[chdemko]

I have no idea of how this error can append. Currently, I have so much time to look after issues. I Will have a look in a couple of weeks. Or you can propose a pull request

[eddiekonczal]

I am unsure how to propose a pull request. What is the correct procedure for doing that?

[eddiekonczal]

I now see that I should submit a pull request if I know how to fix the issue; I don't. I'm not a coder, I'm a Joomla! administrator.

[eddiekonczal]

This issue actually occurs under two different scenarios: if you are not logged in, and if you are logged in:

1. If you are not logged onto the site, and visit the URL for the front-end External Login URL (rather than clicking on the menu item itself), you get a "Redirect Loop" error.

What fixed this was to do the following:

Go to: Component -> External Login
Click "Servers"
Click the URL for our CAS server
On the "Server details" tab, set "Login Redirection" to "Main Menu > Home" (or any valid menu item)
Click "Save & Close"

2. If you are already logged onto the site, and visit the URL for the front-end External Login URL (rather than clicking on the menu item itself), you get a "Redirect Loop" error.

This is a rare scenario, but did cause problems for us when we tried to advertise a URL that people could follow and log into the site to access registered content. The URL worked when they were not logged on, but resulted in "Redirect Loop" errors if they were logged on and tried to return to the page via the original URL.

[eddiekonczal]

Note: Clearing the cookies allows a logged in user to then re-visit the login URL and log in. However, this is essentially the same as logging someone out so it's not an optimal solution.

[eddiekonczal]

This problem still exists. Are there any plans to address it?