Fossgis workshop: mapserver introduction - Toni Pignataro and Joerg Thomsen¶

Tags: fossgis, geo

(Only the first part, the introduction. I’m not writing down the actual workshop :-)

Webgis means the user can view a dynamic map with just an internet browser: he doesn’t need a full-blown GIS package on his computer.

Basic setup: the user requests something of a generic webserver, which in turn sends on the request to a map server. The UMN mapserver runs as a plain old CGI script. Mapserver uses a configuration file *.map, also called the mapfile. This contains everything that the mapserver needs to know what to do.

Mapserver supports lots of formats:

• Shapefile and geotiff.

• Various raster formats through GDAL: tiff, png, jpg.

• OGR simple features library for vector data: tab, mif, dgn, arcinfo coverages, tiger etc.

• Databases: postgis, arcsde, oracle spatial.

Some main features of UMN MapServer:

• Focus on web mapping, not “real” GIS functionality.

• Speedy and stable. A CGI script means that every web request gets a fresh instance of the software: so IF a problem crops up, the damage stays limited to that one request.

• Multi-platform (linux/mac/windows).

• Runs with every webserver through CGI.

• WMS and WFS. Both as server and as client.

• Support for lots of input formats.

• Completely open source.

• Diagrams in the map.

• Lots of user.

• Overview map, dynamic legend, scale.

UMN MapServer supports WMS. Some comments on that:

• You can use every client to view the WMS data. Compatible…

• … because WMS is a standard of the OGC. You can read the official specs. The page count of those specs is scary, but every one of those specs has 10-20 pages that form the real content, so it is practical to read it sometimes.

• Mapserver can also be used in a cascading way as a WMS client.

• WMS has a couple of possible requests: GetCapabilities, GetMap, GetFeatureInfo, GetLegendGraphic, DescribeLayer, Getstyles, PutStyles.