The basis of AQ uFIND records are WMS layers described in GetCapability documents. These xml documents have initial metadata for discovery and the needed metadata for data access. There are standard, required fields in WMS GetCapabilities, but there are is also a significant amount of flexibility in the WMS GetCapabilities to add additional metadata.
DataFed has extended the WMS GetCapabilities of the data layers found in DataFed, by adding 'machine tags' for the facets found in AQ uFIND. DataFed capabilities also include contact information of the distributor and description of the layers. Another defining attribute of DataFed capabilities docs is that they are divided by dataset, so there is a capability for each dataset in DataFed. With the additional information added to DataFed GetCapabilities, an ISO 19115 metadata document could be created for each WMS map layer in the capability.
Alternatively, wild WMSs can be added to the AQuFIND through a human route and a machine route. WMS GetCap links can be submitted to the metadata editor. This editor will automatically extract the metadata available in the WMS capability doc, and then will provide a user interface to pick the layers to be added to AQ uFIND and then add the additional required facets keywords as well as optionally adding additional contact information for the registrant, data originator and dataset description. The output of the metadata editor is a url (API) with key/value pairs needed for the creation of an ISO 19115 document. Alternatively, if a user knowns the url structure they can submit a capability doc + key/value pairs with facets to the ISO Creator Service directly.
The ISO Creator Service takes the WMS GetCapabilities doc + the ISO key/value pairs as one input. The other input is the AQ Community Catalog Metadata Record template. The ISO creator then outputs an ISO 19115 document.
The ISO 19115 doc is passed through an ISO validator that validates the metadata document against the ISO 19115 schema, to ensure syntactically it's correct. The doc is then passed through another validation process against the AQ Community Catalog Metadata Record template, to ensure that the catalog records have all required facets and that every record is up-to-date. If the record is missing a piece of metadata, that record is modified to include a placeholder for that field. Once the records are validated, they are saved into the AQ Community Catalog (WAF). Note: Currently, there is not a machine interface to this validator. However, in theory, a catalog that used the same ISO template as we do, could pass their records through the validator using a machine interface and they would also be registered in the Community Catalog WAF.
The ISO Validator also saves records into the local cache, so that the new records are immediately visible in AQ uFIND.
Once the records are in the AQ Comm Catalog (registered in the GEOSS Component and Service Registry), then the GEOSS Clearinghouse harvests the records. Once the records can be found in the Clearinghouse (1 day turn around), then the AQ uFIND queries the clearinghouse and extracts the facet metadata into the local cache.
