WFS Simple - GetFeature operation
Request
Here is the minimal valid data request, returning in GeoRSS format
all features the service advertises:
http://example.com/wfs?service=WFSSIMPLE&version=1.0.0&REQUEST=GetFeature&OUTPUTFORMAT=text/xml
The above example does no more than any normal URL request for content. In many cases, a developer of client software may only need to know this URL (and be able to read the XML response). However, if a large data set is being served, it may be useful to filter the results down to a more managable size.
WFS Simple requires implementing software to handle bounding box queries. This limits the response to those results that fall within (or on the edge of) a rectangular geographic extent. This is specified by including a BBOX parameter as in this example:
http://example.com/wfs?service=WFSSIMPLE&version=1.0.0&REQUEST=GetFeature
&BBOX=-71.00,42.00,-72.00,43.00&OUTPUTFORMAT=text/xml
WFS Simple also requires implementing software to handle time. This limits the response to those results that fall within a particular time range. Time is specified by including MINDATE and/or MAXDATE parameters. The absence of either one of these parameters means that no limit is placed on time in that direction. Here is an example:
http://example.com/wfs?service=WFSSIMPLE&version=1.0.0&REQUEST=GetFeature
&BBOX=-71.00,42.00,-72.00,43.00&
MINDATE=2006-09-12&MAXDATE=2006-09-22&OUTPUTFORMAT=text/xml
In addition to the standard request parameters shown in the table below, a service may OPTIONALLY filter the data returned by including parameters whose key is the name of a variable, and whose value is a regular expression that conforms to Unicode Technical Standard #18. Here is an example based on the "Trees" data set described below under the DescribeFeatureType operation. This request asks for trees for which the value of the "treeType" variable starts with"elm":
http://example.com/wfs?service=WFSSIMPLE&version=1.0.0&
REQUEST=GetFeature&OUTPUTFORMAT=gml3&treeType=elm.*
A client can discover if a variable may be filtered using regex by checking the DescribeFeatureType response for variables whose filter attribute is true. If a service does not support regex filtering, it shall simply not advertise any variables as having a query attribute of true.
| Key | Description | Default Value |
Mandatory? | In WFS 1.1? |
REQUEST |
Data request operation. Value must be GetFeature. | Y | Y | |
TYPENAME |
A list of feature type names to query. Has no meaning in WFS-Simple. Included for conformance with WFS 1.1 |
default | Y | Y |
OUTPUTFORMAT |
Encoding format of the response. Some common possibilities are text/xml, text/plain, or application/x-gzip;subtype=text/xml |
text/xml | N | Y |
MAXFEATURES |
A positive integer indicating the maximum number of features that the WFS should return in response to a query. If no value is specified then all result instances should be presented. | N | Y | |
BBOX |
The general form of the parameter is: |
N | Y | |
TIME |
Constrain the results to return values within these slash-separated Either the start value or the end value can be omitted to indicate no restriction on time in that direction. If the concept of TIME does not apply to the data being served, a service exception should be thrown. |
N | N |
Response
The response to a GetFeature request depends on the output format specified.