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Friday, May 3, 2013

Implementing a donation system with Drupal Commerce


The Drupal Commerce module is a great solution for anyone who wants to have a shop implemented with Drupal. It doesn't matter if you configure the shop from scratch or if you use an installation profile, you can have a shop in a very short time. Most of the time is just configuration, almost no coding required.
By default, you can create your products, set the prices for them, categorize them, create rules for tax handling, use different payment gateways (also with the help of some contributed modules) and many many other things. Unfortunately there is one thing you cannot do just with configuration: a donation system. The main problem in the donation system is that the amount of each donation can be different. If your donation system has only fixed amounts, then there is no problem, all you have to do is to create one product for each donation amount. But when the amount is variable, then implementing this using only configuration may not be so trivial (if not possible at all).
I will explain next how we deal with this case, when we have to build such platforms.

The concept

If we go a bit deeper and check how the Drupal commerce system is built and how the price of the order is calculated, we can see that each line item from the order has a unit price field, that usually is populated with the price of the product to which it is associated. So the user clicks on the button to add the product to the cart, and this triggers the creation of a line item in the order that will have the unit price of that product. But in our case, the price of the product is variable, because it is about a custom amount that the user wants to donate, so we cannot really use that price to populate the line item. We will have to handle this by ourselves, to implement some logic that will populate the unit price of the line item with the amount of the donation. The solution involves site configuration, as well as some coding.
The main idea is to have a new field on the line items (a price field) that will be populated with the value the user wants to donate, and then using a rule that will be triggered on the event “Calculating the sell price of a product” to put the value from our custom field into the price field of the line item. The reason why we do not just put the value directly in the line item price field, when we create the line item, is that the price of the line item can actually be updated later. For examplecommerce_cart_order_refresh() would update the price of the line items. In this case, our code that populates the unit price will not be executed, and we will not be able to maintain the correct price of the line item. That's why we use that rule that fires on the “Calculating the sell price of a product” and we store the amount that is being donated in a separate field that will not be altered by any other code.

The setup

And this is how it works:
add a price field on the line item type (admin/commerce/config/line-items/product/fields), with the name: field_variable_price
create a product with the SKU “donation” that has the price set to 0
add a rule that updates the price of the line item

 
For the coding part, an example can be found in a sandbox project. An important remark for the coding part is that we actually have to create the order and add the donation product to the order by ourselves, because we have to populate the field_variable_price with the amount that the user want to donate.
The code also has a page: /donate and a configuration form /admin/commerce/config/donation_amounts where some predefined amounts can be configured. For more details about the coding part, you can just check out the sandbox project.
While finalizing this blog post I discovered that, since starting to implement this feature on a recent project, a new module called Commerce Donate surfaced on Drupal.org which might be interesting for you too.

How To: Loading ads in a Drupal AJAX call asynchronously


One of our most recent releases, we were confronted with a challenge: loading ads during a Drupal AJAX (Asynchronous JavaScript and XML) call. This is how we solved it.

The issue

By definition synchronously loaded JavaScript can only add objects like files, content or ads to a page's structure until it is entirely rendered. An additional complexity that can occur while working with third-party advertising providers is that you can not control the performance of their infrastructure. Which means either you accept this risk or try finding a way to mitigate it. We went for the latter.
At this point it is important to stress that it is common practice for third party ads to use the document.write method which only works for the synchronous loading approach. To learn more about the synchronous and asynchronous loading of remote tags I suggest you read the article "synchronous vs. asynchronous tags - what’s the big deal?" on the krux blog. In our case however it became apparent that our solution had to include the asynchronous approach.
While researching possible solutions I found the following tools:
The issue with the the majority of them were, that active development or support wasn't visible, except for PostScribe. This solution offers the following features:
"Krux PostScribe enables the type of tag execution required by most ad formats in an easy-to-use-and-deploy format. It leverages innerHTML to ensure reliable, fast ad delivery."
"Unlike other innerHTML-based solutions (e.g., writeCapture, ControlJS, and OpenTag), Krux PostScribe seamlessly enables the “immediate writes” upon which most ad formats depend."
Which in plain English enables the quick rendering of the page to the user and allowing the ads to respond in their own time without reducing the user's experience.

How to use PostScribe

Download PostScribe directly from its github repository.
Include these files in your project:
/htmlParser/htmlParser.js /postscribe.js
Here is a small example:
<div id="myAd"></div> <script type="text/javascript"> $(function() { postscribe('#myAd', '<script src="remote.js"><\script>'); }); </script>

Our use case

As mentioned in the introduction this solution stems from LikeMag which, besides utilizing PostScribe, is a responsive website and uses the Isotope library to arrange items over the screen automatically depending on the viewport.
Since there are no free lunches on the web, LikeMag has to monetize too and one of their models is built around ads. So in order to deliver the perfect balance between content and ads for every viewport, we had to find a way to render the perfect amount after the identification. And that is moment the where PostScribe comes into play.
Instead of injecting the ads right into the Drupal view and slowing down the loading of the rest of the page, we just print the standard items. In a next step the system iterates over the items and adds the appropriate amount of ad containers to the content with jQuery. (These containers can be addressed with PostScribe, because PostScribe works best when the DOM is ready.)
LikeMag.com Ad
"But where is the AJAX you mentioned in the title?", I hear you cry. So let's talk about it right now. When we scroll down on LikeMag, which besides being responsive is a smart infinite scroll site too, new items will be loaded through an AJAX call. So here we can use PostScribe as we did before. The only thing that we have to check, is that we do not add ads to already "adified" content. In our case we can check if the view-item was already processed by Isotope.
Code from View, partially modified by isotope and postscribe
See the code as an example:
Drupal.behaviors.ViewsLoadMore = { attach: function(context, settings){ if ($(context).hasClass('view')) { $isotope = $('.view-id-articles .view-content'); $isotope.isotope('insert', $('.view-id-articles .view-content .views-row:not(.isotope-item)'), function(){ isotop_load_more_init(settings); Drupal.behaviors.advertisment.loadads() }); } else if ($(context).find("html").length == 1){ // If it contains html, it is the first behavior call. isotop_load_more_init(settings) } } } 
loadads: function(){ $('.view-articles .views-row.views-row-ad').once('postscribe',function(){ if(typeof(cachebuster) == "undefined"){var cachebuster = Math.floor(Math.random()*10000000000)} if(typeof(dcopt) == "undefined"){var dcopt = "dcopt=ist;"} else {var dcopt = ""} if(typeof(tile) == "undefined"){var tile = 1} else {tile++} var string = '<scr'+'ipt src="http://ad-emea.doubleclick.net/adj/likemag.ch/;' + dcopt + ';tile=' + tile + ';sz=300x250;ord=' + cachebuster + '?"></scr'+'ipt>'; postscribe($(this), string); }); } 
As you can see we process only the newly loaded items from the Drupal view and exclude the already processed items.
With this solution we are very flexible to deliver the page content as fast as we can while not depending on the speed of an ad-provider.

Drupal behaviors: A quick how to


If you’re adding JavaScript to your custom module it is very easy and tempting to simply add it like this:
jQuery(document).ready(function($){ alert(‘hot dog flavored water’); }); 
Now this code works perfectly fine but what if your JavaScript needs to be executed on page load and after an AJAX request? Imagine you have a view that uses “Views Infinite Scroll” and you want add a CSS class to every result like this:
jQuery(document).ready(function($){ $('.view-display-id-page .views-row').addClass('fancy-pants'); }); 
This will work for the results that are displayed initially but for all the results that are loaded by Infinite Scroll's AJAX call the class is not added. That’s where Drupal behaviors come in handy.  The behaviors will be executed on every request including AJAX requests, so let's do the equivalent of the code above but this time using this method:
Drupal.behaviors.infiniteScrollAddClass = { attach: function (context, settings) { $('.view-display-id-page .views-row').addClass('fancy-pants'); } }; 
I admit that was quick - so here are some explanations:
  • infiniteScrollAddClass: This is your namespace and should be unique. For example, this is typically the name of your module, but it isn't mandatory.
  • context: This is actually really really cool, on page load the context will contain the entire document and after an AJAX request will have all the newly loaded elements. This way you can treat content that is loaded in via AJAX differently than others.
  • settings: This contains information passed on to JavaScript via PHP, it is similar to accessing it via Drupal.settings. For further comprehension I recommend this source.
There obviously are cases where some functionality should not be executed on every request. In such a case its great to use jQuery's .once() method. So let's say we want to give all the initially loaded results in our view an additional class, for something like this we would proceed like so:
Drupal.behaviors.infiniteScrollAddClass = { attach: function (context, settings) { // these are the elements loaded in first $('.view-display-id-page').once(function(){ $(this).find('.views-row').addClass('i-was-here-first'); });  // everybody $('.view-display-id-page .views-row').addClass('fancy-pants'); } }; 
This will add the class “i-was-here-first” to all the view results present on page load, everybody else joining in via AJAX will just get the “fancy-pants” class.
So that’s a quick look at Drupal behaviors, if you haven’t used it do use it!
If you are looking for additional theoretical insight into this topic I can recommend these two sources for further reading:


5 Drupal Security Tips


Drupal is one of the most secure content management platforms around. Despite its high level of security, it is still vulnerable to certain types of security problems. Many of the potential security problems are preventable if you know what to look for. Here are five security tips for Drupal.
1. Security Updates
Some security problems are actually just loopholes that are found in certain developmental versions of the platform. Security loopholes can actually open to door to malware, hacking, and other attempts to compromise the security of the website. One easy solution is to stay with the recommended distributions until the developmental versions have been stabilized. Be sure to keep everything up to date whenever new releases are available because they will usually have the security solutions that you need to keep your site secure.
2. Be Selective About 3rd Party Modules
Third party modules can help your website run faster and offer some helpful features, but you should use them with a grain of salt. Unfortunately, there are some third party modules may actually create some security issues that may not have been present otherwise. In order to prevent this, it is recommended that you carefully review each one before installation. Try to stick with the ones that are recommended by other users and be sure to look through it yourself to see if there are any problems.
3. Regularly Change Passwords
You should always use tough passwords to ensure the security of your website, but another thing you should be doing is changing your passwords regularly. Hackers can penetrate your system if you use the same passwords continuously, which is common as many people do that because it can be difficult to remember a lot of passwords. It is vital that you change your passwords at least every 3 months for all of your entire system.
4. Monitor Other User Accounts
 Although it is perfectly fine to have other users, their privileges should be carefully monitored and restricted. Sometimes security issues can occur when other users inadvertently let in malicious code or even invite other users. Make sure that they must have permission to make posts, change settings, or add code to your website.
5. Backup, Backup, Backup
As always, backing up yours system is essential. If you do not backup your system, then it will be much more difficult to recover from a security issue that has significantly altered your website. The best solution to this problem is to perform regular backups. Go through all of the steps to make sure that your information is still there.
Securing your Drupal website is relatively easy to do as long as you follow these general guidelines. Be careful about what you allow other users to do with your site, backup your information, change your passwords, update your modules, and be selective about using third party modules. If you do all of this your site will more than likely stay safe.

Drupal SEO Checklist for 2013


The SEO environment has changed significantly during the last 18 months, especially after the Panda and Penguin updates. What worked a couple of years ago, is just not relevant anymore. Before those updates, it was much easier to achieve high rankings in search engines just by building or buying links from low quality sites. Post-penguin SEO requires a more holistic approach, with focus on quality content but also requires a technical perfection.
But, Drupal is already SEO friendly; you are going to answer. Of course it is, but that does not mean that it is perfect right out of the box, but that it has the flexibility to become a SEO-perfect platform. A plain Drupal installation does not provide everything that is required so, here are the basic steps to optimize it to the last detail.

Planning

  1. Begin with the Search Optimization planning, before beginning to build the site. The development of the website is the not the final destination after all, it’s just the medium for the creation and promotion of site’s content. 
  2. Do your keyword research to understand what people are looking for and how you can help them to find it. Plan your site architecture, hierarchy and layout based on your findings. Use the Keyword Tools from Google or Bing. For a more advanced tool, use KeywordSpy (paid, with a free trial).

Setting up Drupal

  1. Create a redirect between the www and the non-www version of your site. If you don’t, search engines will index both versions and you will have a duplicate content issue. It really does not matter which version you’re using, but stick to one. To enable it, open the .htaccess file and uncomment the related lines (lines 81-82 with the www version, lines 87-88 without the non-www version).
  2. Install the SEO Checklist module. This module does not provide any functionality by itself, but it gives you a 58-points checklist for the most important actions related to the On-Site SEO. It helps to keep things organized and it also provides some automated tests for installed modules etc.
  3. Enable Clean URLs. This one is more than obvious, must check it just in case.
  4. Install and configure Pathauto module. The default URL for a Drupal node page is node/nid. Use this module to define URL patterns for every content type, taxonomy and user pages. Now, every time you create something new, a URL alias will be created automatically, which will be search engine friendly. For better results, try to limit the URL length to 115 characters.
  5. Install and configure Global Redirect module. In the previous step, we actually created a duplicate URL for every piece of content. When search engine’s spiders visit the site, they will actually track two different pages and it’s very possible to have a duplicate content penalty. This module solves this problem by creating 301 redirects from the original to the alias URL.
  6. Install and configure Redirect module. If you change the URL in a page which is already indexed in a search engine, when a user clicks on this specific result will land on a 404 error page on your site. You’ll also lose the benefit that you had from existing incoming links to this page. This module creates redirects from the old to the new alias and improves the search experience of the users.
  7. Install and configure Pathologic module. It fixes images paths and URLs inside your content, so that you can move them in different domains, subdomains or folders without creating broken links.
  8. Install and customize Transliteration module if you are creating a web site in a language different than English and you want to use only US-ASCII characters in your URLs.
  9. Create an account in Google Analytics and install and configureGoogle Analytics module. Google Analytics does not only have information about traffic, but it can also provide useful insights about the performance of the site’s landing pages for different keywords.
  10. Install XML sitemap module. Do not forget to configure the module and declare the content types and taxonomy terms that you want to be included in it the XML sitemap. 
  11. Create an account in Google Webmasters Tools and submit the XML sitemap. This is a step, which is often overlooked. After the creation of the XML sitemap do not forget to submit it in GWT. Make a check a after a while that it was submitted successfully and there were no errors.
  12. Create an account in Bing Webmasters Tools and submit the XML sitemap. We all tend to focus on Google, but as Bing has now a market share of 16%, it is an important player that you cannot ignore.
  13. The default robots.txt of Drupal works fine in most cases, but some minor changes are usually required. In many cases you want to hide specific pages or folders of the site for search engines, by adding a new line with the “Disallow” command and the name of file or folder.
    Also, add the URL of the XML sitemap inside the robots.txt file.
    If you’re running a multi-site Drupal installation, use RobotsTxtto generate different files for every one of them.

Optimizing Pages

  1. Install Meta tags module. It allows the creation of patterns for automated generation of meta tags in the <head> section of the page. You can define global settings, but also different settings for every content type, taxonomy, file type or users.
  2. Configure page titles from meta tags settings.  Every URL should have a page title; it is the main definition for search engines and their users, about the page’s content.  To be compatible with the main search engines, try to limit the title’s length to 65 characters. Also, avoid duplicate page titles.
  3. Configure meta descriptions from meta tags settings. Meta description is not a ranking factor, but is the text that users read in the search engine results pages.  The automated generation method uses the first paragraph from your text, so it’s not always ideal. It’s better to take a quick look before posting a node and adjust accordingly.  Avoid duplicate meta descriptions and try to limit their length to 156 characters.
  4. Do not bother to use the keyword tag. Search engines stopped using it several years ago, so it’s not a ranking factor anymore. Actually, it can only help your competitors, as they can easily understand what keywords you are targeting for.
  5. Use proper heading tags. Drupal usually does it right by default, as node pages ,pages created by the Page Manager or Views, are using <h1> titles. Also, secondary elements like blocks or panes are using <h2> titles. Things to watch: some themes are using <h1> to display the site name, so be sure that you do not have two <h1> tags per page. Also, when you are creating your template overrides, be sure that you are using the appropriate markup for heading tags.
  6. Add the rel=”canonical” link element to declare the preferred version for search engines, among the different URLs that a Drupal page has. It can be performed through the meta tags module settings. 
  7. Use the <alt> attribute for your images. Without it, search engines cannot understand the content of the image. Remember that you can have search engine visibility not only for pages, but for images as well.
    When you’re using an image field, you can enable the alt attribute, through the field settings and then add it for every new image.
  8. Optimize your image file names. Using a descriptive file name helps to achieve better rankings. Also, it is the first piece of text that is displayed in Google Images results, so an appropriate file name will attract more clicks.
  9. In many cases you create nodes in Drupal (like images, or tweets), with the only purpose to be included in other nodes, views or panels. To completely hide those pages from search engines, you can use the Rabbit Hole module, which creates redirects from this nodes to custom paths, so they are not visible or crawlable.
  10. Pay special attention when you are creating multilingual web sites. Translating only the site’s content and header tags is not enough. Every important element like page titles, page descriptions and alt attributes should be translated as well.
  11. Install and customize microdata module. Using microdata to markup you pages according to schema.org specifications, will increase the change for rich snippets to be displayed in search engine results pages and will have as a result increased visibility for your web site and clicks from the search engines. Alternatively, you can use RDFa.
  12. Social signals are becoming an important ranking factor, so it’s good to add social share buttons to your pages. There are many different modules for this task, like Social Share or Share This. Even better use custom code, as described in the Google Analytics social integration guidelines.
  13. You may read that Google+ is a failure or it’s dead. The truth is that even if it’s still a small network, it’s growing fast. In many cases Google+ is an important ranking factor for Google. So, creating a page in Google+ is a beneficial strategy.  Also, use rel=”publisher” to connect your website with your Google+ page. 
  14. Google authorship provides several benefits related to SEO. In many cases, it adds the author’s picture in the search results, thus increasing trustworthiness and click-through rates. Also, it generates a “more from author” button, to check other posts from the same author.  So, first ask your site authors to create personal profiles in Google+ and add the site details in them.  Then, add the rel=”author” attribute, a way to do it in Drupal is described here.
  15. If you’re creating a news website, optimize your site for Google news. Generate a Google news site map by installing the relatedmodule Also, consider using the news keyword metatag (yes, it’s a keyword metatag!) to help Google to better understand your content. 
  16. Be careful when you’re using https. Many times both the http and the https versions of your pages will be indexed as separate pages.  Search in Google for “site:yourdomain.com inurl:https”  to locate duplicate content. Use robots.txt to keep search engines from indexing https pages.
    Consider also to switch the whole site to https, as Matt Cutts from Google says in a comment that it’s OK to do it.
  17. Unfortunately, Views or Panels do not have meta tags by default. Install and configure the Meta Tags Quick module, which allows the addition of the main meta tags for any path that is generated by Drupal.
  18. For the pager links of paginated content like Views, use rel=“next” and rel=“prev”. An easy way to do it is described here.
  19. Faceted Search is a great feature and very helpful for site visitors. If it’s not handled right though, it can cause serious problems to the site’s SEO. First of all, the generated URLs are containing a lot of parameters and are not search engine friendly. Faceted API Pretty Paths module solves this problem, as it allows the creation of URLs with an appropriate format. Also, as every filter and every sorting option creates a new URL with an extra parameter, even a small site with a few nodes can generate thousands of different URLs and gave a duplicate content issue. The correct use of canonical tags can eliminate this conflict.

Launching and beyond

  1. Hide or delete your development site. Your client will not like it when it is ranked higher than the production site in search engines. 
  2. On the other hand, if you put a “Disallow: /” in your robots.txt file, remember to remove it, so that search engine’s spiders can crawl your new web site.
  3. Site speed is a factor in search rankings, and it also affects conversion rates.  Read carefully the Drupal caching, speed and performance guide and optimize every aspect to your web site to the maximum.
  4. Use Screaming Frog to quick analyze your site and detect possible issues. Check for client and server errors, broken links, titles, headers, images and be sure that your new site is error-free.
  5. Forget the traditional link-building methods. Create a content creation and promotion plan and acquire links through social media and relationship building. Do not expect to rank well just because you stuffed some nice keywords and you are using Drupal.
  6. Be a part of the Search Engine Optimization Drupal group or chat on irc://irc.freenode.net/drupal-seo
SEO does not end with site launch, but it is a continuous process. Google algorithm changes about 500-600 times a year, so you have to be sure that everything is up-to-date. Make monthly audits in your website, study your analytics, check that all the new content is SEO optimized and make sure that no issues were causes by new functionality or updated modules.