Add a Like button to category/tag/taxonomy pages

tax-like-it.js

jQuery( document ).on( 'click', '.pt-tax-like-it', function() {
	var $this = jQuery(this),
		id = jQuery(this).find('.like-button').attr('data-id'),
		nonce = jQuery(this).find('.like-button').attr("data-nonce");
		
	jQuery.ajax({
		url : taxlikeit.ajax_url,
		type : 'post',
		data : {
			action : 'pt_tax_like_it',
			id : id,
			nonce : nonce
		},
		success : function( response ) {
			jQuery( '#like-count-'+id ).html( response );
		}
	});
	 
	return false;
})

tax-like-it.php

<?php

    add_action( 'wp_ajax_nopriv_pt_tax_like_it', 'pt_tax_like_it');
    add_action( 'wp_ajax_pt_tax_like_it', 'pt_tax_like_it');
    function pt_tax_like_it() {


        if ( ! wp_verify_nonce( $_REQUEST['nonce'], 'pt_tax_like_it_nonce' ) || ! isset( $_REQUEST['nonce'] ) || ! isset( $_REQUEST['id'] ) ) {
            exit( "No naughty business please" );
        }

        $id = $_REQUEST['id'];

        if ( get_term_meta( $id, '_pt_tax_likes', true ) ) {
            $likes = get_term_meta( $id, '_pt_tax_likes', true );
        } else {
            $likes = 0;
            add_term_meta( $id, '_pt_tax_likes', $likes, true );
        }

        $new_likes = $likes + 1;

        update_term_meta( $id, '_pt_tax_likes', $new_likes );

        if ( defined( 'DOING_AJAX' ) && DOING_AJAX ) {
            echo $new_likes;
            die();
        }
    }

    add_action( 'wp_enqueue_scripts', 'pt_tax_like_it_scripts', 100 );
    function pt_tax_like_it_scripts() {
        if ( is_tax() || is_category() || is_tag() ) {
            
            if ( !wp_script_is( 'jquery', 'enqueued' ) ) {
                wp_enqueue_script( 'jquery' ); // Comment this line if you theme has already loaded jQuery
            }

            wp_enqueue_script( 'tax-like-it', trailingslashit( plugin_dir_url( __FILE__ ) ).'js/tax-like-it.js', array('jquery'), '1.0', true );

            wp_localize_script( 'tax-like-it', 'taxlikeit', array(
                'ajax_url' => admin_url( 'admin-ajax.php' )
            ));
        }
    }

    function pt_tax_like() {
        global $wp_query;

        $like_text = '';

        if ( !is_tax() && !is_category() && !is_tag() ) return;

        $tax = $wp_query->get_queried_object();
        $id = $tax->term_id;
        $nonce = wp_create_nonce( 'pt_tax_like_it_nonce' );

        $likes = get_term_meta( $id, '_pt_tax_likes', true ) ? get_term_meta( $id, '_pt_tax_likes', true ) : 0;

        $like_text = '
            <a class="pt-tax-like-it">
                <button class="like-button" data-id="' . $id . '" data-nonce="' . $nonce . '">' . '
                    <span id="like-count-'.$id.'" class="like-count">' . $likes . '</span>' . '
                </button>
                            
            </a>';

        echo $like_text;
    }

usage-tax-like.php

<?php pt_tax_like();?>