ptg This page intentionally left blank Download from www.wowebook.com ptg LESSON 22 Content Management Systems and Publishing Platforms Throughout the course of this book, you’ve learned how to build websites by hand, creating HTML pages one by one. In this lesson, you learn how to use applications to manage aspects of your website. These types of applications are generally called content management systems, and I explain how to use them to keep track of your content so that it’s easier to publish and maintain. In this lesson, you learn the following: n How content management systems came into being n How to decide whether to use a content management system for your website n What the common types of content management systems are n How to work with hosted web applications in general n How to use four popular content management applications: WordPress, Drupal, TypePad, and MediaWiki Download from www.wowebook.com ptg The Rise of Content Management Content management systems were invented to deal with the complexity and tedium of managing large collections of HTML documents by hand. A content management system is an application that manages website content in a form that’s convenient for editing and maintenance and publishes the content as HTML. Some content management systems generate HTML programmatically on-the-fly, whereas others generate static files and publish them. Most content management systems are web applications themselves. Users enter and manage content via HTML forms, and the content management system takes care of storing the content in a database of some kind. Generally, content management systems provide some kind of facility for creating templates and then merge the content entered by users with the templates to produce a finished website. When templates are updated, all the pages that use those templates automatically have the changes applied to them. Content management systems were initially deployed at the largest sites, such as online news sites, online catalogs, and technical sites that published lots of data. These systems were generally custom built and rather complicated. Content management eventually became an industry unto itself, with many companies producing large, expensive systems aimed at publishers, large corporate websites, and other customers who had lots of web content and a few hundred thousand dollars to spend to deploy a system to manage that content. At the same time, content management systems aimed at individuals also became increasingly popular, except that they weren’t called content management tools. Instead, they were called weblogging (blogging) tools, wikis, photo galleries, and so on. These days, most websites are built using content management systems of some kind, and some of the largest and busiest websites utilize content management tools that were originally aimed at individuals running small sites. For example, one of the busiest sites on the Web, Wikipedia.org, is an encyclopedia written and edited by volunteers that was built using a content management system called a wiki. Wikis started out as a way to make it easy for individuals to quickly publish content on the Web without any knowl- edge of HTML. Now you can download and use MediaWiki, the tool behind Wikipedia, free of charge. You’ll learn more about it later in this lesson. Content Management in the Cloud These days, many web publishers do not even host their own content management sys- tems. They subscribe to applications provided by companies that specialize in managing these sorts of applications. So, for example, instead of installing the WordPress blogging tool, you can just sign up for an account at WordPress.com and set up your blog, 658 LESSON 22: Content Management Systems and Publishing Platforms Download from www.wowebook.com ptg avoiding the task of downloading WordPress, installing it on a server, and making sure that it all works. The advantage is ease in getting started and reduced maintenance over time, and the disadvantage is lack of control. When you set up your own copy of WordPress, you can install your own themes and plug-ins, or even modify WordPress itself if you need to. Using the version of WordPress provided by WordPress.com elimi- nates some of that flexibility. The other major trend in web development is sites making it easy to use content from websites on other websites. In Lesson 12, “Integrating Multimedia: Sound, Video, and More,” you learned how to upload videos to YouTube and then embed those videos in your own pages. Doing so enables you to avoid the hassle of encoding video yourself, renting space to put the videos online, and providing a player that works in every popular browser. Allowing this kind of flexibility is becoming increasingly common. So, rather than going out and finding one tool that gives you all the features you require, you can mix and match tools as needed to offer your users exactly the kind of experience you want. By combining services that provide content management, user community features, and multimedia hosting, you can offer your users capabilities that, not too long ago, would have been completely out of reach for the individual web publisher. Right now, in an afternoon, you can create a new blog on WordPress.com, populate it with videos hosted on Vimeo, and allow your users to discuss the videos using a third-party comments tool like Disqus (http://disqus.com/). Is a Content Management System Right for You? It might seem odd to talk about using an application to manage your content now after you’ve worked through 21 lessons explaining how to build web pages from scratch. However, those skills will serve you well whether you use a content management system or not. Content management systems can take a lot of drudgery out of web publishing without limiting the amount of creativity you can apply in designing your web pages. Some work is involved in learning, setting up, and customizing a content management system. When you’re creating a website, it’s probably easier to start with just a few static files and leave aside the content management system. As your site gets bigger, though, at some point the work involved with dealing with static files offsets the initial investment required to start working with a content management system. You have to figure out whether that initial time investment will be worth the effort. Is a Content Management System Right for You? 659 22 Download from www.wowebook.com ptg Another common trade-off with content management systems is that they vary in flexi- bility. Some, such as photo galleries, are built to handle specific kinds of content. You wouldn’t use photo gallery software to manage an online news site, for example. Others are more flexible. For example, Drupal is designed as a generic content management sys- tem for any type of content. Generally speaking, the more flexible a content management system is, the more work it is to set up. So, if you know you’re publishing a photo gallery, setting up a photo gallery package probably makes more sense than setting up a general-purpose content management system and customizing it to present photos. In Lesson 20, “Putting Your Site Online,” I talked about the various options for web hosting. A similar set of options is available when it comes to content management sys- tems. You can write your own. This provides the most flexibility, but it can be a huge amount of work. You can install and manage an application that someone else wrote and customize it for your own needs. Generally, to go this route, you need your own server or at least an account with a web hosting provider. The final option is to sign up for a hosted application. For many kinds of web applications, free versions are even available. They make sure that the servers stay up and that the application is running properly, and you just focus on entering your content and making whatever customizations are avail- able. Hosted applications are generally the least flexible, but they’re also the easiest to get started with. Types of Content Management Systems Content management systems can be sorted into rough categories. As you’ve probably figured out, there’s more to it than just deciding to use a content management system. You have to figure out what type of content you have and which content management system makes the most sense for you. In some cases, multiple content management sys- tems may be the answer. You might prefer to publish your writing using a blogging tool and to publish your photos using a photo gallery application. Here’s a discussion of some common types of content management systems. Blogging Tools It seems you can’t escape the term weblog (or more commonly, blog) these days. A web log is just a website where new items are published in reverse chronological order. The items can be articles, links, recipes, photos, or anything else. Generally the most recent items are displayed on the front page, the site maintains an archive of earlier material, and in many cases the site allows users to publish comments of their own. You can find blogs on just about any topic of interest, and increasingly blogs are integrated into other types of websites. For example, many magazines and newspapers publish blogs as part of 660 LESSON 22: Content Management Systems and Publishing Platforms Download from www.wowebook.com ptg their sites. Companies are using blogs to communicate directly with their customers. Political campaigns are using them to get their message out. In large part, the reason blogs have taken off is that the format is easy to work with. You can publish short items as frequently as you like, and users know that when they visit the site they’ll always see the latest and greatest information right up front. In this lesson, I discuss a blogging package you can install yourself called WordPress as well as a hosted blog tool called TypePad. Google also offers a hosted solution that’s free to use called Blogger, which you can find at http://www.blogger.com, and many people are starting to use Tumblr (http://tumblr.com), a tool that makes it easy to create a blog around snippets found on other sites. You may want to check them out, too. Community Publishing Applications Community publishing applications are similar to blogging tools in that they are usually built around publishing items by date right up front. They differ from blogging tools in that they are more centered around providing features for all the site’s users, not just the site’s author or authors. Generally, these applications enable users to register as members of the site, submit stories, and engage in discussions among themselves. Sites that incor- porate this kind of functionality include http://reddit.com/ and http://digg.com/. Drupal (http://drupal.org) is the most popular application in this category right now. It’s a community publishing system written in PHP. The application is written in a modular fashion so that you can include only the features you want. Wikis Wiki-style systems take the most radical and counterintuitive approach to content man- agement. Most wikis not only allow anyone to view articles but also to edit them. Some wikis require users to register before they can view or edit articles, but the wiki philoso- phy is that every user is an editor. When most people hear about this concept, they imag- ine that the result will be anarchy, but as long as there is a critical mass of users who want the wiki to be useful, this type of system is resistant to attempted defacement. Wikis generally keep a history of changes made to every article, so it’s easy to go back to an older version of a page if someone deletes things he shouldn’t or otherwise submits unwanted changes. The most famous wiki is Wikipedia (http://wikipedia.org), an online encyclopedia writ- ten and edited by volunteers. Not only can anyone view the articles in the encyclopedia, but they can also edit them. If you know something about Fargo, North Dakota, that’s not already in Wikipedia, you can look it up there and add your own information. Attempted vandalism is taken care of by volunteers who keep an eye out for it, and volunteers han- dle disputes over controversial content, too. Types of Content Management Systems 661 22 Download from www.wowebook.com ptg The name wiki comes from the name of the original wiki software, which was called WikiWikiWeb, taken from an airport bus route in Honolulu, Hawaii. To read more about the nature of wikis and their history, why not read about them in Wikipedia? The URL is http://en.wikipedia.org/wiki/Wiki. Aside that everyone can edit the pages in a wiki, the other distinguishing feature of wikis is that they generally provide their own markup language rather than HTML. Generally wiki markup is less flexible than HTML but also a bit easier to get the hang of. Unfortunately, wiki markup usually differs between wiki software packages, so learning MediaWiki’s markup language won’t help you out a whole lot if you start using TWiki, for example. Wikis aren’t right for every project. If you want to publish your poetry online, putting it up on a page where anyone can edit it probably isn’t a good idea. On the other hand, if you need a site where a group can collaboratively write documentation for a project, a wiki can be a great choice. Here’s a list of other popular wiki applications and hosts: n WikiWikiWeb (http://c2.com/cgi/wiki)—The original wiki. n MediaWiki (http://www.mediawiki.org/)—The software behind Wikipedia. I dis- cuss it more later in this lesson. You can find a comparison of various wiki software packages at http://en.wikipedia.org/wiki/Comparison_of_wiki_software. There’s also a list of hosted wikis that you can use at http://en.wikipedia.org/wiki/Comparison_of_wiki_farms. Image Galleries As digital cameras have grown more popular, so too has sharing photos online. There are many photo-sharing sites online that you can use to host your photos. Some popular choices include Flickr (http://flickr.com/), Picasa (http://picasa.google.com/), and SmugMug (http://smugmug.com). If you just want to upload pictures and share them with your friends and family mem- bers, these sites provide an easy way to do that. In some cases, however, you might want to host your own image galleries. A number of popular image gallery applications are available that vary in terms of complexity and the extent to which they can be cus- tomized. The good ones take care of creating thumbnails of your images for you so that you can just upload your photos without dealing with image-editing programs. 662 LESSON 22: Content Management Systems and Publishing Platforms Download from www.wowebook.com ptg General-Purpose Content Management Systems There are far too many general-purpose content management systems to list here. Some content management systems are just toolkits that enable you to build something on your own. Others are highly structured with tons of features that you control via configuration, rather than by writing code on your own. Here are some features that these general-pur- pose content management systems tend to have in common: n Templating system—All content management systems provide some way for you to specify how your content will be laid out on the page and how the pages con- taining the content will look. Most templates take the form of HTML files with special markers that indicate where each piece of content goes. In many cases, the templates are just regular PHP, JSP, or ASP pages. In other cases, the content man- agement system will provide its own template language. n Data repository—Content management systems produce web pages, but they usu- ally store the data in some structured format, whether it’s in a relational database or in XML files. When users enter data, it is stored so that the system can merge the data with the templates to generate HTML when the documents are published. n Workflow system—Controlling who gets to edit which content as well as manag- ing processes for moving content from draft to published status are big parts of many content management systems. Some provide rigid systems that you have to work within; others let you modify the workflow to suit your own organization. Generally, complex workflow features are part of larger content management sys- tems. They’re not useful for individuals or small groups. n System for writing and editing content—All content management systems pro- vide some way for you to get your content into the system. Some enable you to enter it using HTML forms; others provide integration with external tools such as Microsoft Word. n System for publishing content—After content is in the repository and has been approved for publishing, a content management system has to merge that content with a template and publish it on a web page. Some content management systems produce actual HTML files; others generate the HTML on-the-fly for every request. Which approach is used usually depends on how much dynamic content appears on the page. Most content management systems that don’t publish static files provide some mechanism for caching so that data that hasn’t changed can be read from the cache rather than being generated dynamically. Types of Content Management Systems 663 22 Download from www.wowebook.com ptg Working with Packaged Software So far, this book has been about building things from scratch. This lesson, on the other hand, is about applying tools to make building things a bit easier. However, as I’ve men- tioned, using existing tools can be a job unto itself. Before you can start using MediaWiki to manage your content, you have to download it and get it installed on a server and configured properly. The same is true with any software package. Even if you go with a hosted solution, you still have to set things up so that the software enables you to accomplish your goals. You may also be wondering at this point why you bothered to learn HTML, CSS, JavaScript, and everything else in between if you’re going to let an application do your work for you. This is one of the most common misconceptions about this kind of soft- ware. Content management systems make some things more convenient, but you’ll still apply all the skills you learned over the course of the book to make your pages look the way you like. Before discussing specific applications, I’m going to discuss some topics that pertain to nearly all applications of this kind: relational databases and deployment issues. Relational Databases In Lesson 21, “Taking Advantage of the Server,” and in this lesson, I’ve brought up the subject of relational databases more than once, but I haven’t explained what they are or how they work. Relational databases are by far the most popular data repository for web applications. There are a number of reasons for that: n They can scale from the smallest to the largest of applications—You can start a website on a web hosting account on a server that’s shared with 50 other people and eventually wind up running 50 servers of your own and use a relational data- base to store your data the entire way. n They are flexible when it comes to the types of data they can store—All rela- tional databases store their data in tabular format. Each record is a row in a table, and the columns describe the properties of each record. In other words, if you have a table to store information about people, every person will have the same proper- ties. The actual structure of your tables can be customized to suit just about any task. You can create a table of links that has names, URLs, and descriptions for each link, or a table of invoices that lists the customer, amount, shipping address, and item ordered for each invoice. The columns in the table can be configured to hold numbers, dates, short strings, large bodies of text, or even binary files. 664 LESSON 22: Content Management Systems and Publishing Platforms Download from www.wowebook.com ptg n You can create relationships between tables—That’s where the “relational” in relational database comes from. You can relate articles to authors, invoices to cus- tomers, or even people to other people within the same table. The relational model is very, very powerful. n Relational databases use a standard query language called SQL (Structured Query Language)—Although some differences exist between database vendors, if you know SQL you can work with just about any relational database. n Relational databases are popular—The basic technology behind relational data- bases hasn’t changed much in the past 20 years, and they are the foundation of many business applications. What has changed is that now several relational data- bases are freely available, providing powerful features once only associated with the most expensive software targeted at large corporations. Relational databases are so popular and common that using them for data storage for an application is often an easy decision. Relational databases are usually deployed as a service that is accessible over the network, much like an HTTP server. The difference is that instead of using HTTP to communi- cate, the database will use its own proprietary protocol. To communicate with a database, you generally need some kind of client or library provided by the database vendor. PHP has clients for most popular relational databases built in, so you can just use the func- tions associated with your database and not install anything extra. Most hosting providers that allow you to use PHP, CGI scripts, or some other scripting environment also provide access to relational databases. You may have to fill out a spe- cial form to have a database set up for you. After it’s set up, your hosting provider will give you the hostname of your database server and a username or password. You can use that information to access the database, or in the case of packaged software, you can use it to configure the software so that it can access the database. After a relational database is installed, all the administrative tasks—from creating spe- cific databases to creating and managing users—are accomplished using SQL. So to con- figure a database for a particular application, you generally create a new user and database for it to use and then run an installation script that creates all the tables that the application needs and inserts the initial data into the database. You hosting provider will often take care of creating the user and database, and you will run the installation script that builds the initial database. Working with Packaged Software 665 22 Download from www.wowebook.com . systems generate HTML programmatically on-the-fly, whereas others generate static files and publish them. Most content management systems are web applications themselves. Users enter and manage content via HTML. and publish it on a web page. Some content management systems produce actual HTML files; others generate the HTML on-the-fly for every request. Which approach is used usually depends on how much. features are part of larger content management sys- tems. They’re not useful for individuals or small groups. n System for writing and editing content—All content management systems pro- vide some