5.8. WMS layer metadata#

5.8.1. Introduction#

OGC Web services (OWS) can combine with a given resource (WMS layer, WFS FeatureType, WCS Coverage, SOS ObservationOffering) associated content metadata is published to the feature document as a reference to a given URL (i.e. an ISO metadata XML document).

MapServer supports both inline (e.g. wms_title , wms_abstract ) and URL-based (e.g. wms_metadataurl_href ) metadata publishing for OWS functions.

MapServer OGC Service Capabilities Formal XML metadata in XML provides value to directory services, which collect metadata to support discovery.

MapServer 7.2 adds support for dynamic publishing of XML metadata to all OGC web services to advertise formal layer metadata.

5.8.2. WMS layer metadata technical details#

If a layer does not pass ows_metadataurl_* metadata, MapServer provides the metadata URL link (ie WMS MetadataURL ) in the OGC function XML. The URL itself points to MapServer’s GetMetadata API. example:

<MetadataURL type="TC211">
  <Format>text/xml</Format>
  <OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://localhost/path/to/ows?request=GetMetadata&amp;layer=road"/>
</MetadataURL>

Supported metadata formats#

MapServer’s layer API supports the ISO 19115 ISO 2003 geospatial standard.

Graph metadata API#

The Layer Metadata API provides formal metadata for any layer object in a Mapfile, with metadata values (title, abstract, keywords, spatial attributes) derived from the Mapfile layer object definition. The metadata response contains useful information (title, abstract, keywords), and access links to related services (WMS, WFS, etc.).

API supports two parameters:

request GetMetadata
layer（Mandatory ）：single-level name value

Missing parameters will result in OGC ogc:ExceptionReport XML.

Request instance

http://localhost/path/to/ows?request=GetMetadata&amp;layer=road

Support for layer metadata through CGI