CakePHP, file uploading, and inconsistent Auth

I have an application built in CakePHP that is doing file uploads. For each file upload, I know the user's id, so I grab it from $this->Auth->user()

Now, what I have found is that when I am on th开发者_开发问答e page, I will upload files while logged in but sometimes when I print_r the $this->Auth->user() it returns nothing back, and then the next time I try a file upload it will come back, all without e logging in or out. It seems extremely inconsistent, in that sometimes it is in there but other times it doesn't see it.

What am I missing? Thanks!

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Why don't set a var in your app_controller to $this->Auth->userModel so it's accessible by the rest of the application.

In my app_controller I call the below in before_filter to set $current_user.

/**
 * Sets a value for current user $current_user.
 * @return boolean
 */
function __setCurrentUser() {
    $user = null;
    if ($user = $this->Auth->user()) {
        $this->set('current_user', $user[$this->Auth->userModel]);
        return true;
    } else {
        return false;
    }
}

Elsewhere in my app, I can access $current_user's id via $current_user['id'].

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You can also always grab userinfo from the Session that is created by AuthComponent. If $this->Auth->user('id') is empty.. I'm wondering if there is actually a valid session! Are you sure you haven't been logged out in the meantime and the page isn't requiring a login for some reason?