NextGIS has completed the development of a mapping subsystem that manages agricultural vector and raster data. This subsystem, built using exclusively opensource geospatial products (GIS was built with Python/Pyramid web-framework and PostgreSQL with spatial extension PostGIS), will hopefully be part of a joint interactive portal for a State information system for agriculture (SGIO Ag) and Situational center for the monitoring of agricultural security integrated win SGIO Ag. Developed by ZAO Lanit, with interests in the Ministry of Agriculture of Russia, this substem deals with three main datasets:
- Boundaries of agricultural fields in Russia
- Remote sensing data for agricultural regions
- Soil maps
And it provides the following functionality:
- Cartographic data visualization
- Uploading of vector and raster data (ESRI Shape, GeoTIFF) с and its rendering
- Extracting for downloading vector and raster data (ESRI Shape, GeoTIFF) for selected extent
- Assigning of ‘events’ for uploaded datasets and quick linking for spatial regions for these ‘events’
- Management of map, layers, and events
- Data access regulation and integration of authorization subsystem with a general authorization system of the main portal.
DB is managed using SQLAlchemy library. PostGIS is managed using GeoAlchemy. Raster and vector data is processed with GDAL/OGR abstraction libraries. Geometries are accessed in Python with Shapely. Map renderings are done with MapScript, which is part of MapServer, and the results of rending are cached with TileCache. Finally, web-client is built with ExtJS 3.4, OpenLayers и GeoExt.