PyWPS and UMN MapServer

PyWPS can integrate MapServer to return results of ComplexData back to the client.

The idea is as follows: if the client requires pywps.Process.InAndOutputs.ComplexOutput to be returned, as reference, usually, a direct link to the produced file is returned. But with MapServer, a WFS, WMS or WCS URL could be returned.

The client can later parse the URL of the resulting ComplexValue file and e.g. instead of having a GeoTIFF file (result of the calculation), obtained from the WCS, it can request a PNG file via WMS.

Requirements

To support MapServer for ComplexOutputs in your PyWPS installation, the following packages have to be installed:

• python-mapscript
• python-gdal
• python-pyproj

Usage

When you are initializing a new process (see process-initialization), you can set the pywps.Process.InAndOutputs.ComplexOutput.useMapscript attribute to True to get it run. Have a look at the pywps.Process.InAndOutputs.ComplexOutput documentation, also for other attributes, like projection or bbox (can be set automatically from georeferenced file). Required format (pywps.Process.InAndOutputs.ComplexOutput.format decides on the output service type (WCS for GeoTIFF and similar, WFS for xml or text, WMS for PNG, JPEG, GIF).:

self.outputMap = self.addComplexOutput(identifier = "map",
                title = "Resulting output map",
                formats = [
                        {"mimeType":"image/tiff"},
                        {"mimeType":"image/png"}
                ],
                useMapscript=True)