apa.html 11.3 KB
<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Appendix A. How this manual was produced</title><link rel="stylesheet" type="text/css" href="manual.css"><meta name="generator" content="DocBook XSL Stylesheets V1.76.0"><link rel="home" href="index.html" title="JpGraph Manual"><link rel="up" href="pt09.html" title="Part IX. Appendices"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Appendix A. How this manual was produced</th></tr><tr><td width="20%" align="left"> </td><th width="60%" align="center">Part IX. Appendices</th><td width="20%" align="right"> </td></tr></table><hr></div><div class="appendix" title="Appendix A. How this manual was produced"><div class="titlepage"><div><div><h2 class="title"><a name="app.how-was-this-manual-produced"></a>Appendix A. How this manual was produced</h2></div></div></div>
        
        <p>Unfortunately we couldn't locate any off-the-shelf system for producing this fairly
            large manual with some special requirements like automatic inclusion of PHP source that
            should be highlighted and in addition rendered by running the scripts and automatically
            include the resulting images in the resulting manual. To solve this we have based our
            solution around a DocBook5 setup with some custom steps that are described below.</p>
        <p><span class="bold"><strong>DocBook5</strong></span></p>
        <p>The source for the manual is written as a number of split <code class="uri"><a class="uri" href="http://www.docbook.org/" target="_top">DocBook5</a></code> XML compliant documents using
                <code class="uri"><a class="uri" href="http://www.w3.org/TR/xinclude/" target="_top">XInclude</a></code> to bring them
            together into one master document. </p>
        <p>The transformation of the XML source files was done by the means of a DocBook XSL
            stylesheet using the <span class="command"><strong>xsltproc</strong></span> XSL processor. (see <code class="uri"><a class="uri" href="http://xmlsoft.org/XSLT/xsltproc2.html" target="_top">libxslt</a></code>) The DocBook5
            style sheets can directly produce either single file HTML or chunked (many files) HTML
            (or XHTML). </p>
        <p>In addition there is a style sheet to produce FO (Formatted Objects) output which can
            be further refined to PDF with the help of the <span class="command"><strong>fop</strong></span> processor (see
                <code class="uri"><a class="uri" href="http://xmlgraphics.apache.org/fop/" target="_top">Apache FOP</a></code>).
            Unfortunately some formatting instructions in the source are lost in the transformation
            to PDF output. This means that some aspects of the manual doesn't come out perfect in
            the PDF output. For this reason the PDF version of the documentation should only be seen
            as a complementary documentation. The master output format is the chunked HTML.</p>
        <p>
            </p><div class="note" title="Note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3>
                <p>In formatting the chunked output we have prioritized to keep down the number
                    of files to avoid many pages with only a small amount of text on them. Our view
                    is that documentation which breaks the pages down to very low levels are
                    extremely tiresome to read.</p>
            </div><p>
        </p>
        <p><span class="bold"><strong>Phing based build system</strong></span></p>
        <p>The overall build process is drive by a <span class="command"><strong>Phing</strong></span> XML build script.
                <span class="command"><strong>Phing</strong></span> (See <code class="uri"><a class="uri" href="http://phing.info/trac/" target="_top">http://phing.info/trac/</a></code> ) is most easily described as a PHP version of the
            Java build system <span class="command"><strong>Ant</strong></span>. It has several advantages compared with a more
            traditional <span class="command"><strong>make</strong></span> setup, the build files are all written in clear XML
            which makes them easy to read and maintain. In addition there are a number of built-in
            commands that makes deploying and handling of files extremely easy compared with a
            traditional make system which must rely on external tools to do everything. </p>
        <p><span class="bold"><strong>Syntax highlighting of example code</strong></span></p>
        <p>The syntax highlighting and handling of the numerous example images initially posed a
            small problem since there are no off-the-shelf good support for handling this. As a
            basic requirement we needed all PHP scripts to be runnable and kept in the normal
            example directories and then automatically included when the DocBook source was
            processed. </p>
        <p>What was needed was some easy way by which we could just mark in the DocBook source
            (and still maintain valid DocBook XML) that we wanted a particular named example
            included and either show just the image, just the source or both. In addition we
            required the source to be syntax highlighted. </p>
        <p>To handle this we had to write some custom tasks to extend Phing. In principal our
            build system works as follows.</p>
        <div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
                <p>When a new example have been added or an old one removed a special target in
                    our build file are run which extracts all scripts from the example sections in
                    the *.XML files. The name of each found example script in the XML source
                    corresponds to an existing PHP script in the Example directory in the JpGraph
                    distribution. A batch file is then automatically created which is subsequently
                    run and all generated images stored on disk.</p>
            </li><li class="listitem">
                <p>When the normal DocBook XSL processing is done all the special example markups
                    in the XML source is replaced with XML tags to include the image and make sure
                    that the referred script is a proper PHP file name.</p>
            </li><li class="listitem">
                <p>After the XSL process has been run all programlisting tags will have a special
                    token, for example "<code class="code">\#\#example0.php\#\#</code>" this then instructs a
                    custom <span class="command"><strong>Phing</strong></span> task to replace the name in the double "#" tags
                    with the corresponding source (in the resulting HTML code). At the same time
                    this source is included it is also passed through the custom syntax highlight
                    filter so that it comes out as proper marked up source which is inserted
                    directly in the resulting HTML file.</p>
            </li></ol></div>
        <p>The overall build system is illustrated in <a class="xref" href="apa.html#fig.documentation-build-system" title="Figure A.1. The documentation build process">Figure A.1. The documentation build process</a></p>
        <div class="figure"><a name="fig.documentation-build-system"></a><p class="title"><b>Figure A.1. The documentation build process</b></p><div class="figure-contents">
            
            <div class="mediaobject"><img src="images/documentation_buildprocess.png" alt="The documentation build process"></div>
        </div></div><br class="figure-break">
        <p>The way the special markup works is that whenever we want a full example (source and
            image) we create a &lt;programlisting&gt; tag with the file name and title within (single)
            "#" characters. For example to include the very first example in this manual we have the
            following tags in the docbook XML source</p>
        <p>
            </p><pre class="screen">&lt;programlisting&gt;#example0|The very first example#&lt;/programlisting&gt;</pre><p>
        </p>
        <p>The first part (before the "|") is the file name without extension that we want to
            include and the second part (after the "|") is the title we want to use. This markup
            will include both the source as well as the generated graph/image directly in the
            resulting HTML.</p>
        <p>When new examples have been added the examples target in our build file is run and
            that extracts all the example script used in the book (in the above example
                "<code class="code">example0.php</code>") and creates a batch file which is then run to create
            all the images used in the examples. </p>
        <p>The syntax highlighting is handled by a custom written filter extensions to
                <span class="command"><strong>Phing</strong></span> which internally uses the PEAR package
                <code class="filename">Pear::Text_Highlight</code>.</p>
        <p><span class="bold"><strong>Notes:</strong></span></p>
        <p>
            </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
                    <p>In the current setup a regular expression in the Phing build script is
                        responsible for replacing the markup in the programlisting with a
                        &lt;figure&gt; tag and a new &lt;programlisting&gt;. This should be done with a
                        custom XSL layer instead and we will update this for the next major
                        revision.</p>
                </li><li class="listitem">
                    <p>Since the syntax highlighting makes use of HTML markup code for the colors
                        the PDF output does not support syntax highlighting</p>
                </li><li class="listitem">
                    <p>For the reference manual we still use our old DB based documentation
                        system which stores all the methods and classes in a DB augmented with
                        source documentation. (We actually prefer this in front of adding a lot of
                        end user documentation with PHPDoc comment sin the source which have a
                        tendency of cluttering up the code as well as making it prone to error since
                        the source files have to be modified in order to update a simple typo in the
                        documentations. Our next step is therefor to update that old system to be
                        able to produce DocBook5 compliant XML for further formatting and
                        processing.</p>
                </li></ol></div><p>
        </p>
    </div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"> </td><td width="20%" align="center"><a accesskey="u" href="pt09.html">Up</a></td><td width="40%" align="right"> </td></tr><tr><td width="40%" align="left" valign="top"> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> </td></tr></table></div></body></html>