Jen Linton, Comtech Services, Inc.
In an eight article series for the e-newsletter, CIDM will be discussing buying tips for typical services and products that you, as an information developer, might be interested in buying.
This is the fourth in our e-newsletter series of purchasing guides for purchasing information-development products and services. In this issue we look at XML authoring tools.
XML Authoring Tools
XML editors are tools used to create valid and well-formed XML source documents. They provide a way to author according to a document type definition or XML schema which defines rules for how content must be structured. Some non-XML authoring tools people use regularly include Microsoft Word and unstructured FrameMaker. These tools display a what-you-see-is-what-you-get (WYSIWYG) interface allowing authors to format and style their documents based on how they appear on the interface. However, they do not require authors to follow a specific structure for creating content. When you author information according to XML, you are required to follow a structure. The XML editor incorporates the structure into your authoring interface. Like HTML, XML provides a hierarchical structure using elements and attributes. XML editors build in features to allow you to select from a list the elements and the attributes you need to create the structure of your document.
Several options for XML authoring tools are now available. Some tools provide an interface much like a Word interface; others have a more programming-like interface. XML editors provide validation against the document type definition (DTD) or XML schema. Because XML is a portable and flexible authoring mechanism, authors can create and open their content in any XML editor they choose. The options for XML authoring tools include
- text editors
- desktop publishing tools with XML support
- XML editors for programmers
- XML editors for writers
Because XML is also closely related to HTML, many of the tools that allow HTML authoring also accept XML content. For example, many use Notepad or other text editors such as EditPad Lite and JEdit for authoring HTML documents. These editors can also be used for XML documents. However, these editors don’t provide real-time validation against a DTD. Authors must know the structure defined by the DTD before authoring. They must know which elements and attributes are allowed in the document structure.
Some of the desktop publishing tools people currently use, such as Framemaker and Microsoft Word, have also incorporated XML support into their products. However, the XML support that is built into these desktop publishing tools not only includes tags for structured authoring but also includes tags for the syntactic information (formatting and styling information) needed to support their WYSISYG interfaces. These tools don’t support validating against a DTD. Instead they introduce proprietary methods to promote structured authoring. These tools, although they have some XML support, cannot be considered true XML authoring tools.
XML was developed for programming. Programmers and web coders started using XML for quick retrieval and reuse of data. These tools, developed for organizing data rather than for authoring content, are perfectly fine tools to use for authoring technical documentation. They support validating against the DTD and provide options for selecting tags, but they often don’t have an on-screen stylesheet and lack some authoring tool features that tend to come in handy for authoring technical content.
For authoring technical documentation or any other kind of prose content, a different kind of XML authoring tool works best. These tools take the features of the classical desktop publishing tools, Microsoft Word and FrameMaker, but build in XML validation support while providing a simple stylesheet to display the content to facilitate editing. The XML content can still be styled using one or more stylesheets for final publishing to the Web, PDF, or a help system.
Features that Count
The features required for your XML authoring tool are highly dependent on who will be using the tool. It is best to determine your users’ needs for an authoring system before purchasing. If authors are more accustomed to programming, they may be more comfortable with an XML validation tool that shows the XML tags and attributes in the interface. Others who are more used to authoring HTML and have a very good understanding of the DTD may want to author directly in a text editor. Most XML writers, however, prefer to author in a tool that hides the tags and provides an interface similar to what they might see in the output.
Most editors are client-based editors, meaning they are applications that live on your computer. However, there are some editors that are web-based. The criteria listed below should be considered for both client-based and web-based editors. Some of the web-based editors have a lighter version of features. Some of the features to look for include
- DTD and Schema validation – The most important feature in an XML authoring tool is its support of validation rules mapped in the DTD or XML Schema. Some authoring tools have a “file > new” option to select the document type you want to work with, a good sign that it supports validation. Some tools also have an option to point to a DTD on your file system to start a new document. Other systems include a wizard to walk you through where to find the DTD to start a new document. You will know that you are pointing to a DTD if your editor provides you with options for elements to enter at a particular point in your document.
- Element insertion – Some editors allow you to pick from a list of elements that are valid at a particular point in the document, which is helpful when you don’t know the DTD rules or the element names that you are allowed to use. In some of the editors, the list is a separate box from which you can choose elements. Others provide a pop-up list when you hit the enter key. Other editors provide a selection list when you start typing a tag name including the “<” symbol. Depending on where the cursor is in the XML document, you will find different lists of elements to select.
- On-screen stylesheet – An on-screen stylesheet is useful if you want to see your content without tags. Because many authors are used to WYSIWYG desktop publishing tools, they want to see how the content might appear without tags. Most tools allow you to customize the on-screen stylesheet to style the content to be readable and facilitate editing. The on-screen stylesheet is not meant to be a substitute for the final production stylesheet, but it can provide a convenient interface to work with when authoring technical documentation. However, if you are using XML to organize data, this requirement may not be a high priority.
- Content management integration – Most XML authoring tools can be integrated into a content management system. It is helpful to store your information in a repository but work through the editor without the need to work in both the editor and the CMS. Authoring tools handle the integration differently. You can have a tight integration with a particular CMS. A drop-down menu in the editor provides a list of options to interact with the CMS functionality. Other tools have a loose integration which allows you to connect with any CMS but doesn’t have features for a specific CMS. If you are using a CMS, it is a good idea to include integration as one of your requirements.
- Quick attribute selection – This requirement complements the element insertion feature. Attributes, like elements, are defined in the DTD. It is convenient if the attributes are presented in a quick look-up table or a pop-up dialog box so that you can easily fill in the values for the attributes for a particular element. Because some DTDs include large lists of attributes, it is virtually impossible to remember all of the options if you were to type them directly into a text editor. A feature that displays an attributes list and values for each attribute is best.
How to Choose
Before choosing the authoring tool to suit your environment, consider viewing demonstrations of tools. Most of the XML tools vendors are more than happy to provide demonstrations of their tools. Many XML authoring tools can be found by researching them online. Type “XML Authoring Tools” or “XML Editors” into your search engine.
The XML editors found in the search engine will give you a starting point. Another alternative is to find XML listservs. A very thorough list can be found at http://xml.coverpages.org/lists.html. Another helpful list is located at http://www.stylusstudio.com/xmldev/.
Once you narrow your lists of authoring tools to a few, consider downloading the trial versions (most of the vendors provide a 15-30 day trial) to eliminate the tools that don’t fit your needs. You must also consider the cost of customizing the tool interface, if needed. Vendors charge for providing professional services to customize or configure the interface. To ensure the tool you choose is the right one, consider the professionalism of the vendor representatives. Because your team will need to work with them closely, it’s best to have a good relationship with them.