Client-side and Server-side webGIS services
The project refers to online cartography and GIS services; in particular on the server side (back-end) development, where the main processing load is not undertaken by the device of the user, and the front-end web cartography, where the user’s computer, i.e. the client, retrieves data from a remote server, processes them accordingly and replicates them on the device’s screen.
At this point, it is important to clarify that the ‘server’ used for the purposes of the present exercises was not remote, but run on the same machine used for the development (localhost).
Server-side GIS services
The main steps followed for the completion of a server-side GIS delivery system can be outlined as follows:
- Installation of the required software of the host machine
- Creation of database, where the geography data will be stored (pgAdmin III)
- Acquisition of the data (from internal repository) and upload to the database (using the designated tool (PostGIS2.0 Shapefile and DBF Loader)
- Creation of a Web Map Service (WMS), workspace, set data source.
- Creation of layers, one for each feature
- Creation of a group layer, which, in practice, is the output map
- Styling of all the layers
Client-side GIS services
This project is divided into two parts. The first part refers to the creation of a map which is compiled on the client computer, within the web browser. In the second part, a combination of a client-side and a server-side map is generated in the same session. The steps followed for both parts are outlined as follows:
- Acquisition of data (OpenLayers 3)
- Addition of a “theme selector”, which turns specific layers on and off and adjustment of its placement on the map application
- Loading vector data: a vector layer with the municipalities of Denmark (Kommune) except for Viborg and adjustment of its appearance, and a layer of the forests of Viborg from the local WMS service (i.e. the local server at
http://localhost:8080/geoserver/wmsand layer name
viborg:forests). It’s worth mentioning that the latter is layer originating from vector data, which is rendered by Geoserver into a raster layer.