OGC Web Feature Service (WFS)

 

Click Add Overlay > OGC > OGC Web Feature Service (WFS) to connect to a WFS server.

You can either

  • Select from previously saved connections (or)
  • Other well-known servers (or)
  • Type in the server address if you know it.

Validate 'Capabilities' XML from server: The WFS capabilities document tells clients exactly which layers, styles, extents, image formats, etc. a server supports. Check this tickbox if you wish the XML returned by the server in this document to be validated.

Capabilities: Displays the XML capabilities document for the OGC WFS in the resizable HTML/XML Viewer dialog for example:

Click OK to return to the OGC Web Feature Services (WFS) dialog. Click Next.

TIP: Connect using SAML 2.0 ECP Profile: SAML stands for SecurityAssertion Markup Language (SAML) version 2.0. Check this tickbox to make connection using the OASIS SAML. See http://docs.oasis-open.org/security/saml/v2.0/ for details of (SAML) version 2.0 Profiles.

If Connect using SAML 2.0 ECP Profile option is selected in the OGC Web Map Services (WFS) dialog then the following Shibboleth Federation Metadata dialog will be displayed:

Enter the URL of the Shibboleth Federation Metadata and click Next to open the Shibboleth Logon Details window.

Option Description
Identity Provider Select the Identity Provider from the drop-down list.
User name Type the user ID to use for authentication when you log on.
Password Type the password to use for authentication when you log on.
Save password in UI settings database (encrypted)

Should Cadcorp SIS Desktop store the password in the UI settings database? The password will be stored in encrypted form for security.

If the Connect using SAML 2.0 ECP Profile option is NOT selected in the OGC Web Feature Services (WFS) dialog then the following OGC WFS Feature Types dialog will be displayed:

Option Description
Server Details Title This is a descriptive title returned by the OGC WFS
Capabilities Displays the capabilities for the OGC WFS in the resizable HTML/XML Viewer dialog.
Available Feature Types

Lists all available feature types. Double-clcik on any type to see more information.

Describe Feature Type...

Displays the XML description of the selected Feature Type in the resizable HTML/XML Viewer dialog.

Click Next.

The OGC WFS Feature Type dialog will be displayed:

Option Description
Feature Type fields/attributes

The list of available columns for the Feature Type. Select All or Subset.

Server Details

Describe Feature Type: Displays the XML description of the selected Feature Type in the resizable HTML/XML Viewer dialog, for example:

HTTP Request Method

Use the drop-down to select the CRS of your choice. See here for more on Coordinate Systems.

Limit Number of Features

To limit the number of features returned, check the tickbox and enter the number in the box.

HTTP Request Method

GET/POST - select the radio button for the required request method.

Connection Type

Dynamic

This option is not currently available.

Local cache

Select this option if you require SIS to download the resulting features to local temporary storage.

This connection type caches the image on the local client. The amount of memory used depends on the size of the image.

Once the data is on the client, SIS does not need to communicate with the server. If the overlay is saved as a part of the SWD, data will be retrieved from the server when the SWD is first opened.

One-off import

Select this option if you require SIS to make a one-off copy of the resulting features that are completely disconnected from the OGC WFS.

This connection type caches the image on the client as a copy of the data. The SWD will not retrieve the data from the server when the SWD is subsequently opened. This connection type allows users to create a local snapshot of the data.

If the data changes on the server, the user will still have a copy of the data as it was before the change was made.

Click Next to open the OGC WFS Filter dialog:

Option Description
No filter Select this option if you use no filter.
Simple filter

Select this option for a choice of:

Spatial Filter - Check this tickbox if you want to create a spatial filter. Select either Intersect with current view extent or Test with currently selected item.

Test to apply - Select the spatial filter operation from the drop-down box.

  • Equals - The Geometries are topologically equal
  • Disjoint - The Geometries have no point in common
  • Intersects - The Geometries have at least one point in common (the inverse of Disjoint)
  • Touches - The Geometries have at least one boundary point in common but no interior points
  • Crosses - The Geometries share some but not all interior points, and the dimension of the intersection is less than that of at least one of the Geometries .
  • Within - Geometry A lies in the interior of Geometry B
  • Contains - Geometry B lies in the interior of Geometry A (the inverse of Within)
  • Overlaps - The Geometries share some but not all points in common, and the intersection has the same dimension as the Geometries themselves.
  • DWithin -
  • Beyond - For future use

Invert - Check this tickbox to invert the spatial test

Property Filter - Check the tickbox if you want to specify a property ("scalar") filter

  1. Select the required available column from the first drop-down box.
  2. Select the scalar filter operation from the second drop-down box.
  3. Enter the search expression for the scalar filter from the third drop-down box.
Specify XML filter Select this option if you require an XML filter. Click More will display a resizeable XML Filter dialog to allow you to specify any filter.

Click Finish.

Using as an example an overlay containing roads, selected in the OGC WFS Feature Types dialog the following displays may be obtained.

Initial display:

After Spatial Filtering with Intersect with current view extent using the Within test:

After Spatial Filtering with Intersect with current view extent using theIntersecttest: