登录后在第一页加载时向wordpress网站添加代码

Question

I'm writing a wordpress plugin where I need to inject a beacon (HTML image tag) into the page on the first page load after the user logs in - i.e. the page they are redirected to. Subsequent page views of the same or other pages should not include this beacon code.

I've tried several ways to do this.

I've added a function to the wp_login hook. From this function I've tried adding another function to the wp_footer hook to output the content.

// in my class constructor
add_action('wp_login', array($this, 'login'));

public function login() {
    add_action('wp_footer', array($this, 'add_beacon'));
}

This didn't work so I tried setting both hooks up front and setting a global variable to indicate first load. That wasn't picked up by my second function and neither was a constant.

// in my class constructor
add_action('wp_login', array($this, 'login'));
add_action('wp_footer', array($this, 'add_beacon'));

public function login() {
    define('FIRST_RUN', true);
}

public function add_beacon() {
    if (defined('FIRST_RUN')) {
        // output beacon
    }
}

Both hook functions fire correctly but whenever I try to make the output of content in the second dependent on the first hook function firing I get no output.

Any ideas how I can do this? Perhaps there's some way I can check without using the wp_login hook at all.

Answer 1

Try using a per session cookie.

The code would be something like:

function my_init() { 
  if ( is_user_logged_in() ) {  
    if (!isset($_COOKIE['beacon'])) {  
      //Track user code / add wp_footer action
      setcookie ('beacon' 'tracked'); 
    }
  }
}
add_action('init','my_init');

(Code not tested.. hopefully you get the idea).

If you're not happy with the cookie, you could store last page loaded by user in the usermeta table... however, you'd have to make a call as to how long since last page load is considered a new session.