Overall Catalog
The model of a catalog is space>time. We add an extra dimension, variable, which has many attributes that are not yet discoverable in a library catalog definition.
Three parts of interest: query, return, harvest.
Query is discovery, return is the response, and harvest allows other catalogs to harvest data.
This standard is similar to the FGDC metadata catalogs (aka library metadata, Z39.50), and the response is FGDC metadata like. In more modern terms, ISOTC211, and ISO 19139 (metadata).
Question is at what granularity do we want the Observations data discoverable. Is data services level enough, or do we want it at the sites level or series level (this only covers down to sites level).
Question about harvest is can we send our catalogs over the wire.
API has some interesting calls, like GetRecords, DescribeRecord, GetRecordByID, GetDomain (to get vocabularies) and Harvest
Overall thought
Yes, we can make the data services discoverable. But fitting the extra dimension of variable into the catalog model may take some work.
How does series (site>time>variable or site>time>Variable && SampleMedium && Method && Unit && Speciation &&..) into the discovery and harvest is the issue. Is variable a subject? and if so, then with all the attributes of variable how do we characterize it?
How does the sensors and observations fit into the OGC catalog model?
Queries
The standard is modeled after library searching, plus additional elements. Basically the standard coverds the common field names.
Experience has shown that we don't need to cover every possiblity, just enough to discover the data service, and/or observation location.
Common Queryable Elements
Data Services Level| Term | WaterML | Note |
|---|
| Subject | "Water Terms" and | Constant based on dataset type? |
| Title | Title of dataservice, Org Name | |
| Abstract | Description of dataservice + list of variable names? | |
| Format | text/xml, WaterML | (database connection?) |
| Identifier | DataServicesCode (network), CUAHSI | |
| type | Water One Flow Webservice | |
| bounding box | Coverage of sites | |
| Association | || |
| Additional Properties | | |
|---|
| Revision Date | Last Update | |
| Creation Date | | |
| Organization Name | Org | |
| hasSecurityConstrints | TBD | |
| Resource Identifier | WSDL? | |
| Parent Identifer | CUAHSI HIS | Need a record for cuahsi his |
| keywordType | Vocabulary Code | |
| TopicCategory | TopicCategory | |
| ResourceLanguage | UTF-8 or | |
| GeographicDescriptionCode | | need to add somthing like region name |
| Temporal extent | | need to add temporal extent for entire dataset |
| Service Type | | |
| Service Version | || |
Common Queryable Elements
Site/Feature LevelTo discover at the site level, we need to include all the series attributes as discoverable.
| Term | WaterML | Note |
|---|
| Subject | | Not sure what applies. Data Sevice level information? |
| Title | Site name | |
| Abstract | N/A | |
| Format | text/xml, WaterML | |
| Identifier | SiteCode, DataServicesCode (network) | |
| type | Water Observation Site + value types | |
| bounding box | | |
| Association | || | Additional Properties | | |
|---|
| Revision Date | Last Update | |
| Creation Date | Start of record | |
| Organization Name | Org | |
| hasSecurityConstrints | TBD | |
| Resource Identifier | SiteCode | Having Rest based location for a site would be good. |
| Parent Identifer | DataServicesCode, Code from catalog database | |
| keywordType | Vocabulary Code | |
| TopicCategory | TopicCategory | |
| ResourceLanguage | UTF-8 or | |
| GeographicDescriptionCode | HUC, watershed name | |
| Temporal extent | | temporal extent for site dataset |
| Service Type | | |
| Service Version | || |
Returns
This is the basics of what gets returned.
Brief
- Bounding Box
- Identifier
- graphic overview... humm
- service type
- service type verion
- title
- type
Summary
Abstract
- CharacterSet
- Creator
- Contributor
- CouplingType
- BoundingBox
- Format
- FormatVersion
- GraphicOverview
- HierarchyLevelName
- Identifier
- Language
- Lineage
- MetadataCharacterSet
- MetadataStandardName
- MetadataStandardVersion
- Modified
- OnlineResource
- ParentIdentifier
- Publisher
- ResourceIdentifier
- ResourceLanguage
- ReferenceSystem
- RevisionDate
- Rights
- ServiceOperation
- ServiceType
- ServiceTypeVersion
- SpatialResolution
- SpatialRepresentationType
- Title
- TopicCategory
- Type (HierarchyLevel)
Full
Some ISO19139 compliant metadata record.