Mapnik - The Missing Manual

3.3. FileSource

A <FileSource> can be used as a child of <Map> to declare named directory paths that then can be referred to as base attribute in for files to read by data sources file, like e.g. the CSV and GeoJSON ones, and for symbolizers that are able to load image files, like e.g. <PointSymbolizer>, <LinePatternSymbolizer> etc.

Table 18. FileSource attributes
Attribute	Value	Default	Description
`name`	string	none

Example 10. FileSource DataSource example

The actual file to be processed in the example below will be taken from path/to/csv-data/file.csv:

<Map>
  <FileSource name='csv-base'>path/to/csv-data</FileSource>
  [...]
  <DataSource>
    <Parameter name="type">csv</Parameter>
    <Paramater name="base">csv-base</Parameter>
    <Parameter name="file">file.csv</Parameter>
  </DataSource>
  [...]
</Map>

Example 11. FileSource Symbolizer example

The actual symbol file being used in the example below will be taken from path/to/symbols/symbol.svg:

<Map>
  <FileSource name='symbols'>path/to/symbols</FileSource>
  [...]
  <PointSymbolizer base='symbols' file='symbol.svg'/>
  [...]
</Map>