J.2. Tool Sets
The following tools are used to process the documentation. Some might be optional, as noted.
- DocBook DTD
This is the definition of DocBook itself. We currently use version 4.5; you cannot use later or earlier versions. You need the XML variant of the DocBook DTD, not the SGML variant.
- DocBook XSL Stylesheets
These contain the processing instructions for converting the DocBook sources to other formats, such as HTML.
The minimum required version is currently 1.77.0, but it is recommended to use the latest available version for best results.
- Libxml2 for
xmllint This library and the
xmllinttool it contains are used for processing XML. Many developers will already have Libxml2 installed, because it is also used when building the PostgreSQL code. Note, however, thatxmllintmight need to be installed from a separate subpackage.- Libxslt for
xsltproc xsltprocis an XSLT processor, that is, a program to convert XML to other formats using XSLT stylesheets.- FOP
This is a program for converting, among other things, XML to PDF. It is needed only if you want to build the documentation in PDF format.
We have documented experience with several installation methods for the various tools that are needed to process the documentation. These will be described below. There might be some other packaged distributions for these tools. Please report package status to the documentation mailing list, and we will include that information here.
J.2.1. Installation on Fedora, RHEL, and Derivatives
To install the required packages, use:
yum install docbook-dtds docbook-style-xsl libxslt fop
J.2.2. Installation on FreeBSD
To install the required packages with pkg, use:
pkg install docbook-xml docbook-xsl libxslt fop
When building the documentation from the doc directory you'll need to use gmake, because the makefile provided is not suitable for FreeBSD's make.
J.2.3. Debian Packages
There is a full set of packages of the documentation tools available for Debian GNU/Linux. To install, simply use:
apt-get install docbook-xml docbook-xsl libxml2-utils xsltproc fop
J.2.4. macOS
If you use MacPorts, the following will get you set up:
sudo port install docbook-xml docbook-xsl-nons libxslt fop
If you use Homebrew, use this:
brew install docbook docbook-xsl libxslt fop
The Homebrew-supplied programs require the following environment variable to be set. For Intel based machines, use this:
export XML_CATALOG_FILES=/usr/local/etc/xml/catalog
On Apple Silicon based machines, use this:
export XML_CATALOG_FILES=/opt/homebrew/etc/xml/catalog
Without it, xsltproc will throw errors like this:
I/O error : Attempt to load network entity http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd postgres.sgml:21: warning: failed to load external entity "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" ...
While it is possible to use the Apple-provided versions of xmllint and xsltproc instead of those from MacPorts or Homebrew, you'll still need to install the DocBook DTD and stylesheets, and set up a catalog file that points to them.
J.2.5. Detection by configure
Before you can build the documentation you need to run the configure script, as you would when building the PostgreSQL programs themselves. Check the output near the end of the run; it should look something like this:
checking for xmllint... xmllint checking for xsltproc... xsltproc checking for fop... fop checking for dbtoepub... dbtoepub
If xmllint or xsltproc is not found, you will not be able to build any of the documentation. fop is only needed to build the documentation in PDF format. dbtoepub is only needed to build the documentation in EPUB format.
If necessary, you can tell configure where to find these programs, for example
./configure ... XMLLINT=/opt/local/bin/xmllint ...