Redirect users based on their roles, is_admin()

Question

I have a frontend login system.

What I want to achieve is -
If users log in at the front page, it will remains at the same page, if admin log in, it will redirect to /wp-admin/ dashboard.

This is my front page login codes.

<?php if( is_user_logged_in() ) { ?>
    <?php 
    /*  
    Template Name: front page   
    */      
    get_header();
    global $user_identity;
    $redirect = $_SERVER['REQUEST_URI'];    
    ?>
            <?php while ( have_posts() ) : the_post(); ?>
                <?php get_template_part( 'content', get_post_format() ); ?>
            <?php endwhile; // end of the loop. ?>  
    <?php } else { ?>
     <form action="<?php echo get_option('home'); ?>/wp-login.php" method="post"     id="main_comment_form" class="comments-form">   
        <h2>Login</h2>
            <div class="row">
                <label for="username">Username</label><br />
                <input type="text" class="text" name="log" id="log" value="<?php echo     wp_specialchars(stripslashes($user_login), 1) ?>" required/>
            </div>
            <div class="row">
                <label for="password">Password</label><br />
                <input type="password" class="text" name="pwd" id="pwd" required/>
            </div>
            <span class="submit"><input type="submit" value=" Login " name="submit"></span>
            <input type="hidden" name="redirect_to" value="<?php echo $_SERVER['REQUEST_URI']; ?>" />       
     </form>
    <?php 
    }
    ?>

Answer 1

You could proceed like that :

add_filter("login_redirect", "wpse_113875_login_redirect", 10, 3);
function wpse_113875_login_redirect($redirect_to, $request, $user) {

 if(is_array($user->roles)) 
     if(in_array('administrator', $user->roles)) 
       return site_url('/wp-admin/');

   return home_url();
   }

This will use the WP login system and redirect users according to their role after login. I think this is easier than building your own script in this case. You could easily add some button or link in front-end to the WP login page. Hope this helps.