WFS Connector Overview

About the WFS Specification

The Open Geospatial Consortium, Inc. (OGC) WFS Implementation Specification allows you to publish feature-level geospatial data to the Web. GML (XML vocabulary for the GIS domain) is used to communicate feature and attribute information to clients. A WFS-enabled client can use this streamed GML as a data source to render a map. From a client perspective, the WFS interface provides a consistent and standardized access interface to data served by different WFS servers, each of which could be working with different data formats and different Internet mapping technologies.

More information on the Web Feature Specification can be found at www.opengeospatial.org and the OGC WFS Implementation Specification can be found at https://portal.opengeospatial.org/files/?artifact_id=8339. Although the latest adopted specification for WFS is 1.1.0, the WFS Connector implements OGC WFS 1.0.0, which is the only WFS version supported in the OGC Compliance Test Suite.

ArcIMS WFS Connector support

The WFS Connector is a Java Web Application that provides an Open GIS Consortium (OGC)-standard Web Feature Service (WFS) interface to data served by ArcIMS Feature Services. A translation engine receives OGC-standard WFS requests and converts them into ArcXML for processing by the ArcIMS Spatial Server. The responses are translated back into OGC standard responses and are returned to the requesting clients.

The supported requests with the WFS Connector are:

GetCapabilities
DescribeFeatureType
GetFeature

In addition, the WFS Connector supports some of the filters from the Filter Encoding Specification 1.0. For a complete list of supported filters, see Supported operations and filters for the WFS Connector.

The recommended prerequisites to using the WFS request handling function in ArcIMS are:

• You have read the Web Feature Server Implementation Specification Version 1.0.0 or 1.1.0 and are familiar with the terminology.
• You ahve read the Filter Encoding Spacifiaction 1.0 or 1.1 and are familiar with the terminology.
• You are familiar with XML, well-formed XML, and valid XML.
• You are familiar with ArcXML. See the ArcXML Programmer's Reference Guide for further information.
• You have at least one ArcIMS Feature Service running.

WFS Connector compatibility with ArcIMS versions

The following lists which version of the WFS Connector is valid and supported with different versions of ArcIMS.

• The WFS Connector for ArcIMS 4.0.1 is available from the ESRI Interoperability Page.
• No supported versions of the WFS Connector are available for ArcIMS 9.0 or 9.0.1. This includes any service packs.
• Beginning with ArcIMS 9.1 and all later releases, the WFS Connector included in the setup is fully supported. The same connector is also supported with any service packs. The WFS Connector and ArcIMS versions must match. For example, the WFS Connector included with ArcIMS 9.1 is not supported with ArcIMS 9.2.

Using multiple versions of the WFS Connector

Your site can host multiple versions of the WFS Connector if:

1. Each connector has a unique URL reference. Common URLs for the WFS Connector are:
   
   

   ArcIMS 9.1 and later versions:

   http://<hostname>/<deploy_name>/com.esri.wfs.Esrimap?CMD=connectorPing

   For more information on this URL, see Administering the WFS Connector.

   URL for WMS Connector for ArcIMS 4.0.1 available from the ESRI Interoperability Page:

   http://<hostname>/wmsconnector/com.esri.wsit.WFSServlet?CMD=connectorPing

2. Each WFS Connector has a unique Capabilities directory. For example, if the Capabilities directory for one version of the WFS Connector on Windows is c:\arcims\wfs, then a different directory name should be used for another version of the connector such as c:\arcims\wfs_alt. For more information on naming the Capabilities directory, see Setting the WFS Connector properties, Capabilities Directory.

WFS Connector limitations

The following is a list of limitations with the WFS Connector:

• The WFS Connector does not implement the optional transactional operations and is, therefore, a read-only WFS.
• A partial list of filters is supported from the Filter Encoding Specification 1.0.
• The WFS Connector requires Feature Services and does not work with Image or ArcMap Image Services.

WFS Clients

Browsers

A browser is the simplest client of a WFS service. As with all the examples in this documentation, WFS requests can be issued through HTTP GET/KVP, which is a URL string. All responses or exceptions are returned to the browser.

ArcGIS Desktop Data Interoperability extension

ESRI provides WFS client functionality as part of the Data Interoperability extension for ArcGIS 9.X. For more information on using the Data Interoperability extension, see the ArcGIS Help.