15 dicembre 2008

Mapserver, msCrossand Grida3Roberto Demontis - Crs4

What are

● MapServer is an Open Source development environment for building spatially-enabled internet applications. ● msCross is a AJAX (WEB 2.0) WEB GIS client ( Mapserver, Web Gis Services ...)

MapServer via msCross● Standard configuration

- Apache web server and mapserver cgi-bin interface [server]

- msCross JavaScript library (Ajax) [client]

● Typical data - Shapefiles ( shp + dbf ), - GRASS ( raster ), - Postgis (database table)

Problems The data to be shown is located in the spooler dir: $EF_SPOOLER owned by the user

+The data access depends on the apache user's privileges

=Lack of security

http://grd3wk01.crs4.it/cgi-bin/mapserv (The server is not accesible outside Crs4)

Solution (minimal) ● The data to be shown is located in the

spooler dir: $EF_SPOOLER owned by the user+

● Use of the CGI Interface inside a script shell executed by the user

=● An enginframe service in the new portal

/enginframe/agisgrid/agisgrid.xml?_uri=//agisgrid/landsuit_mapserver_NEW

(The portal is not accesible outside Crs4)

Solution (minimal)

Interface:● Single map layer (GRASS raster)

● Interactive with Multiple layer (Shapefiles and Grass raster)

Map files:

● Single map layer (GRASS raster)

● Interactive with Multiple layer (Shapefiles and Grass raster)

Solution (minimal) ● The service declaration

<ef:service id="landsuit_mapserver_NEW" hidden="true" ><ef:name>try_mapserv</ef:name> <ef:action result="image/gif" id="get_image"> export QUERY_STRING ${EF_PLUGIN_PATH}/bin/mapserv.sh </ef:action></ef:service>

● The mapserv.sh script#!/bin/shexport LD_LIBRARY_PATH='.....'# the "dd" command removes the "Content-Type..." string/GRIDA3/EFData/AGISGRID/bin/mapserv "QUERY_STRING=$QUERY_STRING" -nh | dd bs=1 skip=25 2>/dev/null

Solution (minimal)

● The JavaScript msCross map object definition

myMap1 = new msMap( document.getElementById('dc_map') , 'standardCornerRight'); if ( window.location.host == 'grd3port.crs4.it:18080')

myMap1.setCgi('/enginframe/agisgrid/agisgrid.xml?_uri=//agisgrid/landsuit_mapserver_NEW' ); else myMap1.setCgi('http://grd3wk01.crs4.it/cgi-bin/mapserv?' ); myMap1.setFullExtent( 1521000, 1560000, 4358000 ); myMap1.setMapFile( '..../data/mscross.map'); myMap2 = new msMap( document.getElementById('dc_ref') );

................... myMap1.setReferenceMap(myMap2); myMap1.redraw(); myMap2.redraw();

Solution (minimal) ● The JavaScript msCross library “?”

this.get_map_url = function() { var my_url; if (_protocol == 'mapservercgi') { ............

my_url = _cgi + '?mode=' + _mode + '&' + _map_file + '&' + ext + '&' + size + '&layers=' + _layers;

...............

replaced with:my_url = _cgi + '&mode=' + _mode + '&' + _map_file +

'&' + ext + '&' + size + '&layers=' + _layers;

AGISGRID ● Data Model: - vector and raster data - GRASS context: location and mapset defined in

WIND e PROJ files ● Data Storing: - Ascii files (raster data) - postgis tables (vector data)● Import:

- postgis table --> psql2shp --> shp+dbf files - gzipped ascii file --> GRASS --> GRASS raster