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How to Build OTP like documentation

doc-build.xml

## Utilities to prepare XML files

### Create XML files from code

If there are EDoc comments in a module, the escript xml_from_edoc.escript can be used to generate an XML file according to the erlref DTD for this module.

Example:

`1> escript $ERL_TOP/lib/erl_docgen/priv/bin/xml_from_edoc.escript ex1.erl`

### Include code in XML

If there are OTP DTD codeinclude tags in the source XML file, the escript codeline_preprocessing.escript can be used to include the code and produce an XML file according to the OTP DTDs.

Example:

`1> escript $ERL_TOP/lib/erl_docgen/priv/bin/codeline_preprocessing.escript \ ex1.xmlsrc ex1.xml`

## Use xsltproc to generate different output formats

### Parameters used in all the the XSL transformations

These parameters to xsltproc are used for all the supported output formats.

docgen Path to erl_docgen's top directory. gendate The date string that will be used in the documentation. appname The name of the application.> appver The version of the application.

### Generate HTML output

When generating HTML one also needs these three pramaters to xsltproc.

outdir Output directory for the produced html files. topdocdir If one builds a standalone documentation for an application this should be set to ".". pdfdir Relative path from the html directory to where the pdf file are placed.

Example:

`1> xsltproc --noout --stringparam outdir /tmp/myhtmldoc \ --stringparam docgen $ERL_TOP/lib/erl_docgen \ --stringparam topdocdir . \ --stringparam pdfdir $PDFDIR \ --xinclude \ --stringparam gendate "December 5 2011" \ --stringparam appname MyApp \ --stringparam appver 0.1 \ -path $ERL_TOP/lib/erl_docgen/priv/dtd \ -path $ERL_TOP/lib/erl_docgen/priv/dtd_html_entities \ $ERL_TOP/lib/erl_docgen/priv/xsl/db_html.xsl mybook.xml`

### Generate PDF

The generation of the PDF file is done in two steps. First is xsltproc used to generate a .fo file which is used as input to the fop command to produce th PDF file.

Example:

`1> xsltproc --output MyApp.fo \ --stringparam docgen $ERL_TOP/lib/erl_docgen \ --stringparam gendate "December 5 2011" \ --stringparam appname MyApp \ --stringparam appver 0.1 \ --xinclude \ -path $ERL_TOP/lib/erl_docgen/priv/dtd \ -path $ERL_TOP/lib/erl_docgen/priv/dtd_html_entities \ $ERL_TOP/lib/erl_docgen/priv/xsl/db_pdf.xsl mybook.xml 2> fop -fo MyApp.fo -pdf MyApp.pdf`

### Generate man pages

Unix man pages can be generated with xsltproc from XML files written according to the different OTP ref type DTDs.

Example:

`1> xsltproc --output my_module.3\ --stringparam docgen $ERL_TOP/lib/erl_docgen \ --stringparam gendate "December 5 2011" \ --stringparam appname MyApp \ --stringparam appver 0.1 \ --xinclude -path $ERL_TOP/lib/erl_docgen/priv/dtd \ -path $ERL_TOP/lib/erl_docgen/priv/dtd_man_entities \ $ERL_TOP/lib/erl_docgen/priv/xsl/db_man.xsl my_refpage.xml`

### Upcoming changes

The output from the erl_docgen documentation build process is now just the OTP style. But in a near future we will for example add the possibility to change logo, color in the PDF and style sheet for the HTML.