Troubleshooting OGC Services in Essentials

Geocortex Essentials supports OGC services (WMS, WFS and WMTS), but – unlike ArcGIS services -  there are a variety of different publishers, each with their own formats and capabilities which can sometimes cause unexpected behavior within Geocortex Essentials applications.  Supporting all these different scenarios has proven to be a challenging endeavor that we continue to try and improve. This Knowledge Base Article will review some of the troubleshooting techniques or workarounds that you can apply if you are running into incompatibility issues with your OGC services within Geocortex Essentials.

Before applying these techniques, it’s important that you review the OGC Map Services Topic in our Online Documentation to identify what specific OGC services and capabilities are supported, and the intended behavior of these within Geocortex Essentials – for example, what you can expect to see if you have a WMS versus a WMS that contains an associated WFS.

Having issues with getting an OGC service to function?  Try some of the following techniques to try and get your service working or identify the underlying problem. 

1. Create a new Essentials Site with your OGC service(s).  Edit the map service and confirm that the Query Provider is set to your desired provider (Ex: WFS, WMS: text/html…) – This is set in the Functional tab when you edit the Map Service.  Ensure that you have your desired functionality enabled for that layer (Ex: Identify, Map Tips, Query, Global Search…).  Refer to our documentation as some of these won’t be possible for certain OGC services.  If you’re adding the OGC service to a site that contains additional services, ensure that the spatial reference/projection of the OGC service is compatible with the primary Map Service.  Note:  Your service might not be visible within Essentials Manager after you add it.
2. Add a viewer to your site, launch the viewer, and see if the layer draws.  If the layer does not draw, see if it's out of scale range.  If you receive an error, you’ll likely need to add the OGC service to your viewer’s proxy.config.  If you’re still having issues finding the layer, try adding a basemap service in the same projection and zoom into an area where you expect the OGC service to be displayed (Especially if you see a spatial reference error in the viewer or console logs – F12). Get the layer to draw before proceeding.
3. Try and Identify the service in your viewer.  If it’s a WMS, then you’ll only be able to perform point identifies.  If it’s a WMS with an associated WFS, then both point and rectangular identifies should work (Try both point and rectangular to test).  Always try and add the WFS to your Essentials site if possible, as you’ll have more functionality available. View the console logs (F12) for any errors.  
4. If using a WMS not backed by a WFS, identifies usually return feature information in a non-readable format (Ex: WMS: text/html).  You can use a Query Transform Workflow to change the values at runtime and reformat the attributes (So they’re readable).  If you want to modify the results of a WMS identify, you can contact our support team or review our documentation on creating a Query Transform Workflow. 
5. If you see some odd errors, try adding the OGC service to ArcGIS Online and see if you can obtain your desired behavior (identify, query…) within Esri’s AGOL Map Viewer.  Check the console logs (F12) in AGOL to see if you encounter the same errors.  It’s likely that if your OGC service doesn’t work properly in AGOL, then it won’t work in Geocortex.
6. If you have a WMS and are still encountering odd behavior/errors, review the Capabilities xml.  (For example, you can view the capabilities supported by a WMS (https://geodata.nationaalgeoregister.nl/weggeg/wms) by appending the following to the end of it (https://geodata.nationaalgeoregister.nl/weggeg/wms?request=GetCapabilities).  You may want to use Fiddler to make the GetCapabilities request as some responses will not render in a browser and will be saved to your Downloads instead.  Check that the GetFeatureInfo operation is an included operation (This allows you to identify/search etc...). 
7. If you have a WFS, check the WFS GetCapabilities xml by adding the parameters ?request=GetCapabilities&service=wfs to the WFS URL.  Check to see if the GetFeature and DescribeFeatureType operations are included in the GetCapabilities xml.  Ensure that the WFS Feature Type names match the same names as the WMS Layer Names by comparing both the WMS & WFS GetCapabilities xml’s.  If they don’t match or if one’s missing, then you might run into issues (Either contact our support team or get in contact with your WMS/WFS provider).
8. If you receive some errors when loading WMTS services, try a diffferent Tile Matrix Set or Request Encoding in the Functional tab when editing the Map Service in Essentials Manager.  You might also want to adjust the image format set in the Display Settings tab.

If you’d like to view some sample OGC services running in our HTML5 Viewer, you can access the following site:  https://gedemo.geocortex.com/Html5Viewer/index.html?viewer=OGCViewer

You’ll find 4 different services – A WMS that has a QueryTransformWorkflow enabled, a default WMS, a default WFS and a default WMTS.

If issues persist after trying these steps, contact our support team and they’ll try and see if there are any additional workarounds to get your OGC service working.