Database Reference
In-Depth Information
created, you can publish the layers that are available for that PostGIS store. You
have seen in this recipe how easy the whole process of using the GeoServer Web
Administration interface is.
To define the layer style to render features, GeoServer uses the
Styled Layer
Descriptor
(
SLD
)schema,anOGCstandardbasedonXML.Wehavewritten two
distinct rules in this recipe to render, in a different way, the counties that have
an area greater than 5,000 square miles from the others. For the purpose of ren-
dering the counties in a different way, we have used two
<ogc:Rule>
SLD ele-
ments in which you have defined an
<ogc:Filter>
element. For each of these
elements, you have defined the criteria to filter the layer features, using the
<o-
gc:PropertyIsGreaterThanOrEqualTo>
and
<ogc:PropertyIsLessThan>
elements.AhandywaytogenerateanSLDforalayerisbyusingDesktopGIStools
thatareabletoexportanSLDfileforalayer(QGIScandothis).Afterexportingthe
file, you can upload it to GeoServer by copying the SLD file content to the
Add a
new style
page.
Having created the WMS and WFS services for the counties layer, you have been
testingthembygeneratingtherequestsusingthehandyLayerPreviewGeoServer
interface (based on OpenLayers), and then typing the requests directly into a
browser.Youcanmodifyeachservicerequest'sparametersfromtheLayerPreview
interface or just change them in the URL query string.
Intheend,youtestedtheservicesusingQGISandhaveseenhowitispossibleto
export some of the layer's features using the WFS service.
See also
If you want more information about GeoServer, you can check out its excellent
documentationat
http://docs.geoserver.org/
,orgetthewonderful
GeoServer Begin-
ner's Guide
book by Packt Publishing (
http://www.packtpub.com/geoserver-share-
