Skip to content

Secondary Namespaces

What is a secondary namespace?

A secondary namespace is one that is referenced indirectly by the main schema, that is, one schema imports another one as shown below:

a.xsd imports b.xsd
b.xsd imports c.xsd

(using a, b and c as the respective namespace prefixes for a.xsd, b.xsd and c.xsd):

a.xsd declares b:prefix
b.xsd declares c:prefix

The GeoTools encoder does not honour these namespaces and writes out:

"a:" , "b:" but NOT "c:"

The result is c's element being encoded as:

<null:cElement/>

When to configure for secondary namespaces

If your application spans several namespaces which may be very common in application schemas.

A sure sign that calls for secondary namespace configuration is when prefixes for namespaces are printed out as the literal string "null" or error messages like:

java.io.IOException: The prefix "null" for element "null:something" is not bound.

Note

When using secondary namespaces, requests involving complex featuretypes must be made to the global OWS service only, not to Virtual Services. This is because virtual services are restricted to a single namespace, and thus are not able to access secondary namespaces.

In order to allow GeoServer App-Schema to support secondary namespaces, please follow the steps outlined below:

Using the sampling namespace as an example.

Step 1:Create the Secondary Namespace folder

Create a folder to represent the secondary namespace in the data/workspaces directory, in our example that will be the "sa" folder.

Step 2:Create files

Create two files below in the "sa" folder:

  1. namespace.xml
  2. workspace.xml

Step 3:Edit content of files

Contents of these files are as follows:

namespace.xml(uri is a valid uri for the secondary namespace, in this case the sampling namespace uri):

<namespace>
    <id>sa_workspace</id>   
    <prefix>sa</prefix>
    <uri>http://www.opengis.net/sampling/1.0</uri>
</namespace>

workspace.xml:

<workspace>
    <id>sa_workspace</id>   
    <name>sa</name>
</workspace>

That's it.

Your workspace is now configured to use a Secondary Namespace.