Setting build parameters with .properties files

Usually, DITA builds require setting a number of parameters that do not change frequently. You can reference a set of build parameters defined in a .properties file when building output with the dita command. If needed, you can override any parameter by specifying it explicitly as an argument to the dita command.

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.

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.