DAPS 2.4.0

How to Write an Article with DocBook and DAPS

Tutorial

Authors: Vanessa Wallfahrer and Tanja Roth
Publication Date: June 14, 2017

DAPS is an open source program for transforming DocBook XML into output formats such as HTML or PDF. DAPS is command line based and runs on Linux*.

In XML-based publishing, layout and contents are strictly separated: while writing, you only focus on the contents and the XML tags to use. The layout for different output formats is defined in so-called stylesheets and is automatically applied when converting the XML into output formats.

This tutorial is for DocBook and DAPS beginners. Previous knowledge of XML is not required, but you need basic knowledge of using the Bash Shell. We will write a recipe for a chili sauce in DocBook and convert it into HTML. The tutorial explains step-by-step how to set up your document, which basic XML tags to use for writing it, and how to produce the output shown in Figure 1.

The Goal: Publishing a Recipe for a Chili Sauce in HTML Format
Figure 1: The Goal: Publishing a Recipe for a Chili Sauce in HTML Format

1 Why Should I Use DocBook and DAPS?

DocBook is a markup language for technical documentation. Content is tagged with XML elements according to its meaning. This is similar to sorting objects into drawers according to their function: For example, you place scissors and tongs into a drawer labeled Tools, whereas you place teddies and building blocks into a drawer labeled Toys. Similarly, when writing documents with DocBook, you would sort the author's name into an XML tag called author, whereas you would sort a reference to another document into an XML element called xref.

While this might seem cumbersome at first sight, it is a huge advantage when considering the different output formats you can generate from the same XML sources. Imagine you want anything tagged with an xref element to appear in blue in HTML output, whereas you want it to appear in green in the PDF output. Or you decide at one point that you want references to other documents (xrefs) to be displayed in red in all output formats from now on. This can be achieved without changing anything in the XML files themselves. It is only a matter of defining in the stylesheets which color to use for xref elements in different output formats.

With DAPS, you can convert your XML sources into various output formats with one command. DAPS takes care of converting any images in your documents automatically into the format best suited for the selected output format. DAPS also makes writing and editing more efficient by providing additional features like editor macros, spell checking or link checking. With daps you can also control which stylesheets to use for generating output.

2 What You Need

The first step is to install a few packages, including an editor with XML support for more efficient writing. Recommended is Emacs and DAPS version 2.0 or higher. Follow the steps below to install Emacs and DAPS:

  1. Open your terminal and log in as root by entering

    tux:~> su -

    Note that tux:~> or (root # below) stands for your prompt. Do not type that part.

  2. Enter your root password.

  3. Install Emacs with zypper:

    root # zypper in emacs
  4. Install DAPS with zypper:

    root # zypper in daps

3 How to Start

To be able to process the XML files, DAPS requires a specific directory structure. Either use daps-init or set it up manually. The daps-init command is especially advisable for beginners, because it creates an example and the necessary structure. File names always end with .xml.

3.1 Working with daps-init

The daps-init command creates a working environment for DAPS. In this case, it creates a directory called tutorial. It contains a DAPS configuration file for your tutorial (DC-tutorial), the DocBook XML file located in the XML subdirectory and a subdirectory containing image files (images). The image directory will be relevant later (see Section 4.7, “Integrating Images”).

  1. The daps-init command creates a working environment for DAPS. It builds a directory with the specified filename. This directory contains a DC-file, a xml subdirectory and a image subdirectory. The image directory (see Section 4.7, “Integrating Images”) will be relevant later.

     daps-init --docdir recipe -r article
  2. Now you can start working on your text. To learn about the needed XML tags, read the following chapters. If you need help with DAPS, open the daps-init man page in your terminal:

    tux:~> daps-init --help
  3. Open the XML file (recipe/xml/MAIN-daps-example.xml) in your editor and use it as a reference.

  4. Open the Documentation Configuration file (recipe/DC-daps-example) in an editor and use it as reference.

  5. Proceed with Section 4, “How to Write”, where we will create another XML file and another DC file from scratch (in addition to the files created by daps-init) and use them to write the recipe.

3.2 Working without daps-init

This method is suitable for the more experienced writer.

  1. For working without daps-init, create a directory with your project name and two subdirectories, called xml and images. Open a terminal.

  2. tux:~> mkdir recipe
  3. tux:~> cd recipe
  4. tux:~> mkdir -p images/src/{dia,eps,fig,pdf,png,svg} xml

    Now you have created the required directory structure that is needed by DAPS.

  5. Create a DC-file, which is a configuration file for your project. Open a new file and paste the following lines with your XML file name instead of "MAIN-daps-example.xml". See below.

3.3 Creating an XML File and a Documentation Configuration File

Now we will create an XML file (that we will use in the following to write the recipe) and a Documentation Configuration (DC) file (that we will use later on to convert the XML file into HTML output).

  1. To create the XML file:

    1. In a terminal, switch to the XML subdirectory.

      tux:~> cd xml
    2. Open a new file, and paste the following header into it (see Example 1, “Header of a DocBook File”), or copy this from MAIN-daps-example.xml.

      Example 1: Header of a DocBook File
      <?xml version="1.0" encoding="utf-8"?> 1
           <!DOCTYPE article PUBLIC 2
           "-//OASIS//DTD DocBook XML V4.5//EN"
           "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
      
           ]>

      1

      XML-Declaration for XML V1.0, encoding UTF-8

      2

      The general syntax for a document type declaration

      Don't be afraid if you don't understand the header. Just insert it by copy and paste into your file.

    3. Save the file as recipe.xml.

  2. To create the DC file:

    1. Switch to the directory above (that should be your recipe directory):

      tux:~> cd ..

    2. Open a new file and paste the following line into it: MAIN=recipe.xml

    3. Save the file, for example as DC-recipe.

4 How to Write

4.1 Identifying Start and End Tags

The most important thing you need to know about XML is, that you need to close the tags. Either with an end tag or with a backslash at the end of the tag (for example: <para/>). The content between the tags depends on which element you want to create. Open the XML file recipe.xml that you just created, and place the cursor below the header. To write an article, paste an article start and end tag into the XML file. Between these two tags, write your text as shown in Example 2, “Start- and Endtag of an Article ”.

Example 2: Start- and Endtag of an Article
<article>
Tags and text
</article>

4.2 Adding Metadata

Each article may contain information about its author, publication date, release information, copyright or other metadata. To include such metadata use an article info element and enter the following data (see Example 3, “Article Info Header”):

Example 3: Article Info Header
<article lang="en" id="art.template">1
<title>Little G's Ceylon Bang</title>2
<articleinfo>
<releaseinfo>
  2013-10-213
</releaseinfo>
 <author>4
  <firstname>Tux</firstname>
  <surname>Penguin</surname>
 </author>
</articleinfo>
<abstract>5
Recipe for a chili sauce.
</abstract>
</article>6

1

Article start tag.

2

Title for the article.

3

Build date.

4

The author's name.

5

An abstract. What is the subject of your article?

6

Article end tag. It always has to be at the very end of the article.

HTML Output (Article Title and Article Info)
Figure 2: HTML Output (Article Title and Article Info)

4.3 Structuring Your Document With Sections

Each article consists of sections and subsections. Example 4, “Example: Structure With Sections” contains a section and a subsection.

Example 4: Example: Structure With Sections
<sect1>1
 <title>What do you need?</title>
  <sect2>2
   <title>Ingredients</title>
    <para/>
   </sect2>3
   <sect2>
    <title>Equipment</title>
     <para/>
  </sect2>
 </sect1>4
<sect1 id="sec.preparation">
 <title>Preparation</title>
</sect1>

1

Start tag of section level one. Section1 is the parent element of every element that comes below. Always needs a title. Recommended is a para tag in every section.

2

Start tag section of level two.

3

End tag section of level two.

4

End tag of the section level one parent element.

Place the cursor behind the abstract end tag and in front of the article end tag and paste the content of Example 4 into your XML file.

HTML Output (Article With Sections)
Figure 3: HTML Output (Article With Sections)

The image above shows the given XML file example as an HTML page. As you can see in the picture, the section level two is a child element of section level one. It is possible to nest sections.

4.4 Creating Itemized Lists

To create a listing, use the <itemizedlist> tag.

Example 5: Itemized List
<itemizedlist>
 <listitem>
  <para>
   60g Habanero Chilis
  </para>
  </listitem>
 <listitem>
  <para>
   30g Cayenne Chilis
  </para>
 </listitem>
 <listitem>
  <para>
   1,5 Butch T Chilis
  </para>
 </listitem>
 <listitem>
  <para>
   75g Kidney Beans
  </para>
 </listitem>
</itemizedlist>

Place the cursor behind the following line:

<title>Preparation</title>

and paste the contents of Example 5 into your XML file.

HTML Output (Article With an Itemized List)
Figure 4: HTML Output (Article With an Itemized List)

4.5 Providing Step-by-Step Instructions

For writing instructions, it is recommended to do it step-by-step, as you can see in the following Example 6, “Example for Step-by-Step Instructions ”. That way, instructions are easier to understand and browse for the reader.

Example 6: Example for Step-by-Step Instructions
<procedure>1
 <step>2
  <para>3
   Rinse, than drain the kidney beans for about 10 minutes.
  </para>
 </step>
 <step>
  <para>
   Fry kidney beans with some oil.
  </para>
 </step>
 <step>
  <para>
   Puree all ingredients.
  </para>
 </step>
 <step>
  <para>
   Cook for about 5 minutes.
  </para>
 </step>
</procedure>

1

Procedure start tag.

2

If you use <step> elements you can create numeric listed paragraphs. Every further <step> you add automatically counts up.

3

Within <para></para> you can write down your text.

HTML Output (Article with Step-by-Step-Instructions)
Figure 5: HTML Output (Article with Step-by-Step-Instructions)

4.6 Integrating Remote Links and Cross References

4.6.1 Remote Links

To refer to an external HTML page, integrate an internet link in your tutorial.

Example 7: Integrating Remote Link
<para>
 Before you start to cook:
 <ulink url="http://www.crazyhotseeds.com/top-10-worlds-hottest-peppers/"/>
</para>

To get the output shown in Figure 6, place the cursor behind the </para> end tag within the <abstract> element and paste the content of Example 7 into your XML file.

HTML Output (Article with Remote Link)
Figure 6: HTML Output (Article with Remote Link)

4.6.2 Cross References

With cross references (xref elements) you link to paragraphs or examples within your document.

Example 8: Integrating Cross References
<para>
 How to prepare see <xref linkend="sec.preparation"/>1
</para>

...


<sect1 id="sec.preparation">2

1

With <xref linkend="ex.preparation"/> you set a link to the following Preparation title.

2

Set id=sec.preparation at the section, that you want to refer to. Set id=ex.preparation at the paragraph, you want to refer to.

To get the output shown in Figure 7, place the cursor below the <title>Preparation</title> element and paste the contents of Example 8 into your XML file.

HTML Output (Article with Cross-Reference)
Figure 7: HTML Output (Article with Cross-Reference)

As you can see in the screenshot, the underlined part is a link to the sectionPreparation.

4.7 Integrating Images

  1. To integrate an image in your file, save an image (for example, butcht.png) in the image/png directory. That is very important because otherwise, it will not work.

  2. Add an image reference into your XML file.

Example 9: Integrating Images
<figure>
    <title>Butch T Chili</title>1
    <mediaobject>
    <imageobject>
    <imagedata fileref="butcht.png"/>2
    </imageobject>
    </mediaobject>
    </figure>

1

Image title. In the output formats, the title will appear together with the image.

2

The image reference.

HTML Output (Article with Integrated Image)
Figure 8: HTML Output (Article with Integrated Image)

5 Convert Your XML Files

You can convert the XML file at any time, no matter if it is finished or you only want to see the temporary result. Convert as often as you like.

Important
Important

The XML file must be valid, otherwise it will not work! Check if it is valid:

daps -d DC-tutorial validate

5.1 Convert Your XML File Into PDF

  1. Open a terminal and enter run the following command:

    tux:~> daps -d DC-tutorial pdf
  2. DAPS automatically creates a directory called build. You can find your finished PDF file there.

5.2 Convert Your XML File Into HTML

  1. To build an HTML page, open a terminal and enter the following command:

    tux:~> daps -d DC-tutorial html --single
  2. You get a green colored link, which you can open in a browser, for example Firefox.

6 Further Information

If you still have questions or need additional information, read the DAPS man page. Open it in a terminal:

tux:~> daps --help

Alternatively, visit the following links:

Print this page