Setting parameters with .properties files

DITA builds usually require a set of parameters that don’t change frequently. You can define these settings in a .properties file, and reference it when building output with the dita command. You can override any of the properties by specifying them as command-line arguments.

About .properties files

A .properties file is a text file that enumerates one or more name-value pairs, one per line, in the format name = value. The .properties filename extension is customarily used, but is not required.

  • Lines beginning with the # character are comments.
  • Properties specified as arguments of the dita command override those set in .properties files.
    Restriction:
    For this reason, args.input and transtype can’t be set in the .properties file.
  • If you specify the same property more than once, the last instance is used.
  • Properties not used by the selected transformation type are ignored.
  • Properties can reference other property values defined elsewhere in the .properties file or passed by the dita command. Use the Ant ${property.name} syntax.
  • You can set properties not only for the default DITA-OT transformation types, but also for custom plugins.

Procedure

  1. Create your .properties file.
    Tip:
    Copy dita-ot-dir/docsrc/samples/properties/template.properties; this template describes each of the properties you can set.

    For example:

    # Directory that contains the custom .css file:
args.cssroot = ${args.input.dir}/css/

# Custom .css file used to style output:
args.css = style.css

# Copy the custom .css file to the output directory:
args.copycss = yes

# Location of the copied .css file relative to the output:
args.csspath = branding

# Generate a full navigation TOC in topic pages:
nav-toc = full
  2. Reference your .properties file with the dita command when building your output. 
    dita --input=my.ditamap --format=html5 --propertyfile=my.properties
  3. If needed, pass additional arguments to the dita command to override specific build parameters.

    For example, to build output once with <draft> and <required-cleanup> content:

    dita --input=my.ditamap --format=html5 --propertyfile=my.properties \
     --args.draft=yes
    Tip:
    If you are building in different environments where the location of the input files is not consistent, set args.input.dir with the dita command and reference its value with ${args.input.dir} in your .properties file.