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TIPS, INSIGHTS AND THE LATEST FROM THE EXPERTS BEHIND CAKEPHP

RSS Feeds, Fast and Easy

For my first entry, I am going to talk about how to create an RSS Feed on your website. RSS (Really Simple Syndication) is a format used to publish frequently updated works such as blogs or featured products. RSS defines a set of XML elements that are used to describe a channel or feed of information. An RSS feed is comprised of two parts, first is the metadata describing the channel and second is the records that make up the elements of the feed. RSS feeds allow your sites visitors to access the information on your site using software that reads these feeds. This will allow your site's visitors to stay up-to-date on the information on your site.

CakePHP allows for easy integration of RSS feeds into existing controller actions through the automatic router extension parsing. This allows us to specify what type of response we want from a URL through adding the proper extension to the URL such as http://www.yoursite.com/entries.rss. This alerts the router that your are asking for RSS formatted data in return. In addition, CakePHP has an RssHelper class that can be used to output parts of the metadata and elements in the feed through an easy to use helper.

Preparation

Before we begin making the feed we must alert the router that we want to allow for extensions to be parsed in the URL and that we want it to accept .rss as a valid extension. In your sites router file we add the following:

	Router::parseExtensions('rss');

Also for CakePHP to work it magic we must also have the RequestHandler in our controller's $components array. Now the router knows that we would like to parse urls that end in .rss as requesting RSS formatted responses. The next step of preparation is to add a default layout for rss feeds on your site. When you request a different format response the layout that is rendered will be selected from a sub-folder with the same name as the format. So in this case we would need a folder called /rss in the layouts folder in our CakePHP install. The view class will search for a file that has the same name as the layout that would be rendered if you were just rendering the html. In most cases this is the default.ctp layout file in the main layouts directory, but because we are requesting the response in RSS format we must add a default.ctp layout in the /layouts/rss/ sub-directory. This layout is our default RSS Feed layout.

	echo $rss->header();

	if (!isset($channel)) {
		$channel = array();
	}
	if (!isset($channel['title'])) {
		$channel['title'] = $title_for_layout;
	}

	echo $rss->document($rss->channel(array(), $channel, $content_for_layout));

Here in the layout our RssHelper shines through. We use the method RssHelper::channel() which generates the element and associated metadata elements. The $content_for_layout variable contains the output from the view. These then get passed to the RssHelper::document() method, which wraps the RSS document in the respective elements.

Controller

The controller needs no modification in the case of a simple RSS feed. This is because we are only adding a second view that is xml/rss to the action. The same data is used in both views and because CakePHP automatically sets the correct response type we don't need to tell it to render the correct view and layout for RSS. Here is the action method in the EntriesController for a basic view sorted by a published_date field and showing only if it is published.

	public function index() {
		$this->paginate['Entry'] = array(
			'conditions' => array('Entry.published' => 1),
			'order' => 'Entry.published_date DESC');
		$this->set('entries', $this->paginate());
	}

If you do have code that is specific for only the RSS view you can use the RequestHandler::isRss() to see if the action was called with the request for xml/rss formatting on response. This method returns a boolean value based on if the .rss extension was parsed in the URL.

	if ($this->RequestHandler->isRss()) {
		// RSS feed specific code goes here
	}

Note About Channel Metadata

It may feel right to put your metadata information in the index method in the controller, using Controller::set() to send the information to the views. This is inappropriate and is one of the most common snags that we have seen in the CakePHP community with creating RSS feeds. That information which is passed in the layout file to the RssHelper::channel() method should be set in the view using View::set() which will set the $channel variable for the layout in the view.

Views

As we had to put the layout in a subdirectory of the layouts folder we also need to create a view for the index action for the blogs controller. This is done by creating a directory /views/entries/rss/ which will hold our view file that will generate the RSS to render. You will need to add your RssHelper to the list of helpers in your controller so that it is automatically loaded in the view and the layout.

Our view begins by setting the $channel variable for the layout, this contains all the metadata for our RSS feed.

	$homeUrl = $html->url('/', true);
	$this->set('channel', array(
		'title' => __("Daniel's Recent Articles", true),
		'link' => $homeUrl,
		'description' => __("Most recent articles from Daniel.", true),
		'language' => 'en-us',
		'image' => array(
			'title' => 'Recent Articles from Daniel',
			'url' => FULL_BASE_URL . $this->webroot('/img/rss_feed_image', true),
			'link' => $homeUrl));

First we get the URL link for the website home that we will use for the links. Also we set the title, description and image to use for the RSS feed icon. By setting the channel variable using View::set() we are providing the layout the information to render the RSS feed's metadata elements.

The second part of the view generates the elements for the actual records of the feed. This is accomplished by looping through the data that has been passed to the view and using the RssHelper::item() method. The other method you can use, RssHelper::items() which takes a callback and an array of items for the feed. (The method I have seen used for the callback has always been called transformRss(). There is one downfall to this method, which is that you cannot use any of the other helper classes to prepare your data inside the callback method because the scope inside the method does not include anything that is not passed inside, thus not giving access to the TimeHelper or any other helper that you may need. The RssHelper::item() transforms the associative array into an element for each key value pair.

	foreach ($entries as $entry) {
		$postTime = strtotime($entry['Entry']['created']);

		$entryLink = array(
			'controller' => 'entries',
			'action' => 'view',
			'year' => date('Y', $postTime),
			'month' => date('m', $postTime),
			'day' => date('d', $postTime),
			$entry['Entry']['slug']);

		// This is the part where we clean the body text for output as the description 
		// of the rss item, this needs to have only text to make sure the feed validates
		$bodyText = preg_replace('=\(.*?)\=is', '', $entry['Entry']['body']);
		$bodyText = $text->stripLinks($bodyText);
		$bodyText = Sanitize::stripAll($bodyText);
		$bodyText = $text->truncate($bodyText, 400, '...', true, true);

		echo  $rss->item(array(), array(
			'title' => $entry['Entry']['title'],
			'link' => $entryLink,
			'guid' => array('url' => $entryLink, 'isPermaLink' => 'true'),
			'description' =>  $bodyText,
			'dc:creator' => $entry['Entry']['author'],
			'pubDate' => $entry['Entry']['created']));
	}

You can see above that we can use the loop to prepare the data to be transformed into XML elements. It is important to filter out any non-plain text charictars out of the description, especially if you are using a rich text editor for the body of your blog. In the code above we use the TextHelper::stripLinks() method and a few methods from the Sanitize class, but we recommend writing a comprehensive text cleaning helper to really scrub the text clean. Once we have set up the data for the feed, we can then use the RssHelper::item() method to create the XML in RSS format. Once you have all this setup, you can test your RSS feed by going to your site /entries/index.rss and you will see your new feed. It is always important that you validate your RSS feed before making it live. This can be done by visiting sites that validate the XML such as Feed Validator or the w3c site at http://validator.w3.org/feed/.

Latest articles

One CakePHP Project Per Day

The whole team here at CakeDC are big supporters and contributors of the CakePHP community. For this month, I decided to do “one CakePHP project per day” to share with the community.  Here are some of my projects so far:

Project 01 - Notes App

A one page note application using CakePHP 4 and Bootstrap 5. This project is  a good starting point to learn the framework. Link: https://github.com/rochamarcelo/one-project-a-day-challenge-01-notes  

Project 02 - Contact List

An application to manage contacts - you are able to list, add, edit and delete contacts, upload contact avatar images or use avatar images from gravatar.com . It was built using CakePHP 4, plugin friendsofcake/search, plugin josegonzalez/cakephp-upload, Gravatar, and Bootstrap 5.  Link: https://github.com/rochamarcelo/one-project-a-day-challenge-02-contact-list  

Project 03 - Recipe Box

An application to manage recipes, using CakePHP 4,  CouchDB and Bootstrap 5. This one is a good starting point to learn to use CouchDB with CakePHP, including how to list, add and edit recipes (documents). Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-03-recipe-box  

Project 04 - Service Plan with Exchange rate

An application to list services and apply exchange rate using the api https://exchangeratesapi.io/documentation/ and CakePHP 4. In this one you see the custom namespace WebService to handle logic related to api as client. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-04-service-plans-ex-rate  

Project 05 - Polls

A fun poll app, using the awesome Bulma CSS Framework and CakePHP 4. A good example of model association and the CounterCache Behavior. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-05-polls-emmy  

Project 06 - Movie Theater Schedule

An application to see which movies are in the theaters and which hours by screen each day of the week. A good example of complex queries, model associations and seed data. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-06-movie-theater-schedule  

Project 07 - Podcast Finder

An application to help easily find podcasts and download episodes. In the source code you’ll find how to use the itunes api,  a structure to handle Model actions (that I think is a good option to make your models cleaner), and a way to parse podcasts feed (XML); example usage of dependency injection. The application was built with CakePHP 4 and Bulma CSS Framework. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-07-podcast-finder  

Project 08 - Url Shortener

An application to create short urls - a good example of how to create custom routes and use custom primary key types for a model. The application was built with CakePHP 4. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-08-url-shortener  

Project 09 - Quiz

Users can list quizzes, create quizzes and answer at any time. A good example of how to use MongoDB with CakePHP 4 with a base structure for Collection classes.  Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-09-quiz  

Project 10 - File Transfer

An application to easily send files to anyone, create an account, upload the file and inform the person email to send to. Built with CakePHP 4, plugin CakeDC/Users,  plugin Josegonzalez/Upload,  plugin friendsofcake/bootstrap-ui, SMTP and Bootstrap. A good example to see the usage of these plugins. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-10-file-transfer  

Project 11 - Tasks

A one page application for  users to manage their tasks. The user can create and remove decks, create and complete tasks, and list tasks grouped by decks. Built with CakePHP 4, plugin CakeDC/Users and Bootstrap 5 Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-11-tasks  

Project 12 - Blog

A blog website with blog posts and tags management, WYSIWYG editor, blog search, tags filtering. Built with CakePHP 4, CakeDC/Users plugin, friendsofcake/bootstrap-ui, Muffin/Slug, friendsofcake/search and Bootstrap 4 . A good example of usage of custom routes, route prefix, finders and multiple plugins. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-12-blog  

Project 13 - Olympic Medal Count

Perfect time for this project, right?! An application to display olympic medal count by country and sports. The source code uses CouterCache behavior and aggregated query. Built with CakePHP 4 and Bootstrap 5. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-13-olympic-medal-count
 

Project 14 - Smart Home Dashboard

An awesome dashboard to manage smart devices using MQTT Messaging, CakePHP 4, CakeDC/Users plugin, php-mqtt/client (testing with Mosquitto Broker) and Bootstrap 5. The application is able to publish messages to change device status and subscribe for status changes. Link: https://github.com/rochamarcelo/one-cakephp-project-a-day-challenge-14-smart-home-dashboard-mqtt    I hope that this initiative will somehow inspire others to put their Cake skills to work, and share their projects with the community. If you’d like to see my future projects and posts, you can follow me on Twitter, and I will share them all there! https://twitter.com/mrcodex

Logging CakePHP Applications To Team Communication

The log of applications is gold. It's an important part of the software, they represent the health of the application. By default, CakePHP will use the FileLog adapter which will write to /logs/ folder. It's hard to track the live issues, and by hard I mean you will need to connect to the server, open the file on /logs/ and look at the issue which you want to investigate.   What do you think if your application sends the error directly to your team communication (Slack, Teams, RocketChat) application? Will be easier to know about a new error after some deployment? This error is sneaky, and can be in command applications. Often, we only look at the errors when the users report it.   For this sample I will use Slack, but this approach can be implemented for any application.  All we need is to create a Log adapter and configure it. So…let’s bake that:     Now we may get errors like this:   That’s all bakers! I hope this article can be useful and you can improve your logs.  

A CakePHP Docker Development Environment

We sponsor a monthly CakePHP training session (register here https://training.cakephp.org ) where we cover different topics about the framework. One of our sessions, the "Getting Started with CakePHP 4" is aimed to help developers starting a new project quickly and following the best practices.   Our previous "recommended" quick setting for a CakePHP development environment was using a vagrant box. See details here:  https://www.cakedc.com/jorge_gonzalez/2018/01/17/using-a-vagrant-box-as-quick-environment-for-the-getting-started-with-cakephp-training-session. However, we've switched internally to use docker as our primary development environment and also we started using docker in our training sessions.   Here's a quick overview of a simple docker based development environment for CakePHP.  

1. Create a new CakePHP project skeleton using 

composer create-project cakephp/app myproject   A new folder "myproject" will be created with a CakePHP project skeleton inside. Go to this new directory and proceed.  

2. Create a new "docker-compose.yaml" file with the following contents

version: '3' services:   mysql8:     image: mysql:8     restart: always     container_name: mysql     environment:         MYSQL_ROOT_PASSWORD: root         MYSQL_DATABASE: my_app         MYSQL_USER: my_app         MYSQL_PASSWORD: secret     volumes:       - ./:/application     ports:       - '9306:3306'     cakephp:     image: webdevops/php-apache:8.0     container_name: cakephp     working_dir: /application/webroot     volumes:       - ./:/application     environment:       - WEB_DOCUMENT_ROOT=/application/webroot       - DATABASE_URL=mysql://my_app:secret@mysql/my_app     ports:       - "8099:80"
 

3. Run "docker-compose up"

You'll create 2 containers named mysql and cakephp -  check the docker-compose configuration to see default database and users created in the mysql container, and the same environment params passed to the cakephp container via DATABASE_URL to allow the cakephp container to connect with the mysql database.   NOTE: the ports exposed are 9306 for mysql and 8099 for cakephp webserver. You can list them using docker-compose ps.  

4. Access your database and cakephp shell

  • To access the database you can use the command:
mysql --port 9306 -umy_app -psecret my_app   To restore a database dump for example, you can use the command: curl -L https://raw.githubusercontent.com/CakeDC/cakephp4-getting-started-session/master/my_app.sql |mysql --port 9306 -umy_app -psecret my_app   You can also configure any database tool to access the database in: localhost:9306  
  • To access the cakephp environment and shell you can use the command:
docker exec -it --user application cakephp bash   You'll go to the webroot folder, so in order to run the cake shell you'll need to: cd .. bin/cake 
  Now you have a working environment to play with the training session contents.   In this previous article, we covered another approach to setting up a local docker environment: https://www.cakedc.com/rochamarcelo/2020/07/20/a-quick-cakephp-local-environment-with-docker    We hope to see you in our next training session! https://training.cakephp.org   

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