Help! My GeoServer Doesn’t Like My App-Schema!

An in depth look at a GeoServer 2.2 workspace that utilizes the app-schema extension

<*> I don't like how this blog post turned out! You can get the "better" formatted version as a PDF here. <*>

HowTo:File GDB Feature to PostGIS Database

The goal of this post is to get our data from a File GDB to a format that GeoServer can use, specifically a PostGIS GDB. If we try and use a shapefile, the field names will be truncated and this will invalidate your schema that you have worked so hard to conform to the USGIN schema standards.

*Only works for 10.x and up geodatabases. You need to upgrade your gdb to 10.x if you are using an older geodatabase.

One hurdle to using Geoserver to deploy AASG Geothermal Data services is the resolution of schemas. Creating additonal configuration files for Geoserver allows the use of "app-schemas" which will automatically download the indicated web-accessible schema (.xsd) and be referenced in the GetFeature request. This would solve a problem with service deployment using ArcGIS, where custom schema locations is necessary.

This blog will document the problems and break-throughs I've had so far in implementing Geoserver app-schemas. I have not yet been able to get schema resolution, but would like to make a post so that others can take into account my work thus far and chime in about other ideas or advances. This work is based on Tomcat running Geoserver, set up on an Oracle VM VirtualBox. The data for the services are pulled from a PostGIS database.

 

A few housekeeping tips I learned the hard way, for starters:

catalina.sh

The official documentation for the app-schema extension has been revamped! There is a lot more to look through here - absolutely a must-read for anyone interested in using GeoServer to serve GeoSciML features.

http://docs.geoserver.org/trunk/en/user/data/app-schema/index.html

 

I've been in the midst of a daily back-and-forth email discussion with the app-schema developers on the GeoServer-Users mailing list. Reading through the conversation may be helpful, as they've already resolved a number of issues I've had. Here's a link to the thread:

http://www.nabble.com/Geoserver-2.0-availability---included-app-schema-capabilities-td24624783.html

I'm almost done building a complete mapping file that will output GeoSciML MappedFeatures from polygon features in a database that follows the NCGMP09 schema. This schema, developed as part of the USGS National Cooperative Geologic Mapping Program, is a proposed standard database schema for the publication of single digital geologic map. An ESRI Personal Geodatabase implementation of the NCGMP09 schema is available on the website linked above.

It works! Once you get the app-schema extension installed and the tutorial data in place, it works just fine. Make sure that in your GetFeature requests you specify the outputFormat as GML3, as it won't work at all in GML2 (which GeoServer defaults to if no outputFormat is specified).

Also, be aware that the app-schema extension is only supported at WFS version 1.1.0.

Now I can move on to beginning to map my data into GeoSciML features. I'll write some more walkthrough as I put it together.

I'm starting the process of implementing a WFS that delivers GeoSciML data. I intend to make Group Posts here detailing what I'm trying, what works, what doesn't, in the hopes that it wil both help me keep track of what I've done, and also be of use to someone else attempting to do something similar. If I find things that are of particular use, I'll end up making more formal walkthroughs. I'm coming at this without having much background in open-source software, OGC services or XML, so I'll have a lot to learn.

I want to help make the process of building a GeoSciML WFS server easier. I'll be collecting links to relevant information, cookbooks, walkthroughs, etc. Hopefully this will chronicle my process of going from knowing practically nothing about how to implement a service to making one work.