I have been working on an online **[newspaper/blogging application][1]** with *CodeIgniter 3.1.8* and Twitter Bootstrap 4.
The latest feature added is *lazy loading* of posts.
From the **Static_model** (`application\models\Static_model.php`), which is responsible with the general settings, I can set `$data['is_ajax_loading']` to `true` and enable loading posts via AJAX.
In the Posts controller, I have:
class Posts extends CI_Controller
{
public function __construct()
{
parent::__construct();
}
private function _initPagination($path, $totalRows, $query_string_segment = 'page')
{
// load and configure pagination
$this->load->library('pagination');
$config['base_url'] = base_url($path);
$config['query_string_segment'] = $query_string_segment;
$config['enable_query_strings'] = TRUE;
$config['reuse_query_string'] = TRUE;
$config['total_rows'] = $totalRows;
$config['per_page'] = 12;
if ($this->Static_model->get_static_data()['has_pager']) {
$config['display_pages'] = FALSE;
$config['first_link'] = FALSE;
$config['last_link'] = FALSE;
$config['prev_tag_open'] = '<li class="prev">';
$config['prev_tag_close'] = '</li>';
$config['next_tag_open'] = '<li class="next">';
$config['next_tag_close'] = '</li>';
}
if (!isset($_GET[$config['query_string_segment']]) || $_GET[$config['query_string_segment']] < 1) {
$_GET[$config['query_string_segment']] = 1;
}
$this->pagination->initialize($config);
$limit = $config['per_page'];
$offset = ($this->input->get($config['query_string_segment']) - 1) * $limit;
return array(
'limit' => $limit,
'offset' => $offset
);
}
public function index()
{
//call initialization method
$config = $this->_initPagination("/", $this->Posts_model->get_num_rows());
$data = $this->Static_model->get_static_data();
$data['base_url'] = base_url("/");
$data['pages'] = $this->Pages_model->get_pages();
$data['categories'] = $this->Categories_model->get_categories();
$data['search_errors'] = validation_errors();
$data['posts'] = $this->Posts_model->get_posts($config['limit'], $config['offset']);
$data['max_page'] = ceil($this->Posts_model->get_num_rows() / 12);
$this->twig->addGlobal('pagination', $this->pagination->create_links());
// Featured posts
if ($data['is_featured']) {
$data['featured'] = $this->Posts_model->featured_posts();
$this->twig->addGlobal('featuredPosts', "themes/{$data['theme_directory']}/partials/hero.twig");
}
$this->twig->display("themes/{$data['theme_directory']}/layout", $data);
}
public function search()
{
// Force validation since the form's method is GET
$this->form_validation->set_data($this->input->get());
$this->form_validation->set_rules('search', 'search term', 'required|trim|min_length[3]', array(
'min_length' => 'The search term must be at least 3 characters long.'
));
$this->form_validation->set_error_delimiters('<p class = "error search-error">', '</p>');
// If search fails
if ($this->form_validation->run() === FALSE) {
$data['search_errors'] = validation_errors();
return $this->index();
} else {
$expression = $this->input->get('search');
$posts_count = $this->Posts_model->search_count($expression);
$query_string_segment = 'page';
$config = $this->_initPagination("/posts/search", $posts_count, $query_string_segment);
$data = $this->Static_model->get_static_data();
$data['base_url'] = base_url("/");
$data['pages'] = $this->Pages_model->get_pages();
$data['categories'] = $this->Categories_model->get_categories();
//use limit and offset returned by _initPaginator method
$data['posts'] = $this->Posts_model->search($expression, $config['limit'], $config['offset']);
$data['expression'] = $expression;
$data['posts_count'] = $posts_count;
$data['max_page'] = ceil($posts_count / 12);
$this->twig->addGlobal('pagination', $this->pagination->create_links());
$this->twig->display("themes/{$data['theme_directory']}/layout", $data);
}
}
public function byauthor($authorid)
{
//load and configure pagination
$this->load->library('pagination');
$config['base_url'] = base_url('/posts/byauthor/' . $authorid);
$config['query_string_segment'] = 'page';
$config['total_rows'] = $this->Posts_model->posts_by_author_count($authorid);
$config['per_page'] = 12;
if ($this->Static_model->get_static_data()['has_pager']) {
$config['display_pages'] = FALSE;
$config['first_link'] = FALSE;
$config['last_link'] = FALSE;
$config['prev_tag_open'] = '<li class="prev">';
$config['prev_tag_close'] = '</li>';
$config['next_tag_open'] = '<li class="next">';
$config['next_tag_close'] = '</li>';
}
if (!isset($_GET[$config['query_string_segment']]) || $_GET[$config['query_string_segment']] < 1) {
$_GET[$config['query_string_segment']] = 1;
}
$limit = $config['per_page'];
$offset = ($this->input->get($config['query_string_segment']) - 1) * $limit;
$this->pagination->initialize($config);
$data = $this->Static_model->get_static_data();
$data['base_url'] = base_url("/");
$data['pages'] = $this->Pages_model->get_pages();
$data['categories'] = $this->Categories_model->get_categories();
$data['posts'] = $this->Posts_model->get_posts_by_author($authorid, $limit, $offset);
$data['posts_count'] = $this->Posts_model->posts_by_author_count($authorid);
$data['posts_author'] = $this->Posts_model->posts_author($authorid);
$data['max_page'] = ceil($data['posts_count'] / $limit);
$data['tagline'] = "Posts by " . $data['posts_author']->first_name . " " . $data['posts_author']->last_name;
$this->twig->addGlobal('pagination', $this->pagination->create_links());
$this->twig->display("themes/{$data['theme_directory']}/layout", $data);
}
public function post($slug)
{
$data = $this->Static_model->get_static_data();
$data['base_url'] = base_url("/");
$data['pages'] = $this->Pages_model->get_pages();
$data['categories'] = $this->Categories_model->get_categories();
$data['authors'] = $this->Usermodel->getAuthors();
$data['posts'] = $this->Posts_model->sidebar_posts($limit = 5, $offset = 0);
$data['post'] = $this->Posts_model->get_post($slug);
$data['next_post'] = $this->Posts_model->get_next_post($slug);
$data['prev_post'] = $this->Posts_model->get_prev_post($slug);
$data['author_image'] = isset($data['post']->avatar) && $data['post']->avatar !== '' ? $data['post']->avatar : 'default-avatar.png';
if ($data['categories']) {
foreach ($data['categories'] as &$category) {
$category->posts_count = $this->Posts_model->count_posts_in_category($category->id);
}
}
if (!empty($data['post'])) {
// Overwrite the default tagline with the post title
$data['tagline'] = $data['post']->title;
// Get post comments
$post_id = $data['post']->id;
$data['comments'] = $this->Comments_model->get_comments($post_id);
$this->twig->addGlobal('singlePost', "themes/{$data['theme_directory']}/templates/singlepost.twig");
} else {
$data['tagline'] = "Page not found";
$this->twig->addGlobal('notFound', "themes/{$data['theme_directory']}/templates/404.twig");
}
$this->twig->display("themes/{$data['theme_directory']}/layout", $data);
}
}
The script that does the loading:
(function($) {
var currentPage = 2,
maxPage = $('#postsContainer').data('max-page'),
posts = null,
pageUrl = $(location).attr('href'),
pageBaseUrl = pageUrl.split('?')[0],
searchStr = pageUrl.split('?')[1];
$('.pagination').hide();
$(window).scroll(function() {
var toBottom = $(window).scrollTop() >= $(document).height() - $(window).height() - 25;
if (toBottom && currentPage <= maxPage) {
loadMore();
}
});
function loadMore() {
$.ajax({
url: `${pageBaseUrl}?${typeof searchStr === 'string' ? searchStr : ''}&page=${currentPage}`,
type: 'GET',
beforeSend: function() {
if (typeof posts != 'undefined') {
$('.loader').show();
}
}
})
.done(function(data) {
$('.loader').hide();
posts = $(data).find('#postsContainer').html();
if (typeof posts != 'undefined') {
$('#postsContainer').append(posts);
currentPage = currentPage + 1;
if (currentPage > maxPage) {
$('#postsContainer').append('<p class="text-center text-muted">No more posts to load</p>');
}
}
});
}
})(jQuery);
In the `posts-lists.twig` view:
{% if posts %}
{% if is_ajax_loading %}
<div id="postsContainer" data-max-page="{{max_page}}">
{% endif %}
{% for post in posts %}
<div class="post-preview">
<a href="{{base_url}}{{post.slug}}">
<h2 class="post-title">{{post.title}}</h2>
<h3 class="post-subtitle">{{post.description}}</h3>
</a>
<p class="post-meta">
Posted {% if category_name is null %}in <a href="{{base_url}}categories/posts/{{post.cat_id}}" title="All posts in {{post.post_category}}">{{post.post_category}}</a>,{% endif %} on {{post.created_at | date("M d, Y")}}
</p>
</div>
<hr class="posts-separator">
{% endfor %}
{% if is_ajax_loading %}
</div>
{% endif %}
{% else %}
{% if posts_author is not defined and expression is not defined %}
<p class="mt-0 text-muted text-center">There are no posts {% if category_name is defined %} in this category {% endif %} yet.</p>
{% endif %}
{% endif %}
{% if is_ajax_loading %}
<div class="loader"><span></span></div>
{% endif %}
My main concerns are security and code redundancy.
#### Questions:
1. Is the code DRY enough?
2. Are there any security risks?
3. Improvement opportunities?
[1]: https://github.com/Ajax30/Bravecms/