Title

 Harvest, and Query Metadata

 Overview

 Actors and Interfaces

• Service Provider
• GEOSS Common Infrastructure Registry
• GEOSS Clearinghouse
• Clearinghouse Client
  

Initial Status and preconditions

• Service Provider has deployed an online resource of interest to GEOSS. For example:  a data access service, a catalog, a model, an observation service or another  processing ( grid transformation or workflow) or information resource. The resource may also be a service client (online browser client generator or downloadable software component).
  
• Service Provider has published online resource description metadata by registering their service either with the GEOSS CSR "or" in a metadata service (e.g. Community Catalog, Web Accessible Folder) which in turn has been registered in the GEOSS CSR.
  

 Evolution

(basic flow steps)

1. GEOSS Clearinghouse queries GEOSS CSR for registered components and services.
2. GEOSS Clearinghouse extracts from the CSR response the harvest policies and online metadata service links for CSR registered resources.
   
3. For resources which are metadata services or provided metadata links GEOSS Clearinghouse harvests all or part of the available metadata holdings (recommended).
1. The community catalog permits harvesting and holds less than 10000 records. GEOSS Clearinghouse harvests all of the holdings and periodically updates them according to the registered frequency of change.
2. The community catalog / metadata service does not permit bulk harvesting and/or holds more than 10000 records. GEOSS Clearinghouse harvests collection records (aggregate summary) as criteria for dynamically cascading queries to the Clearinghouse from users to the service
4. For resources which are other than metadata services, GEOSS Clearinghouse harvests the service getCapabilities or equivalent resource description and any additional metadata references provided therein. The Clearinghouse assembles as complete as possible a set of discovery metadata records from this information according to its familiarity with that particular service type.
5. (optional) Service Provider issues a manual request to GEOSS Clearinghouse to re-harvest and update metadata sooner than indicated by its registered harvest policy.
   

 Post Condition

 The GEOSS Clearinghouse is prepared to accept and process resource discovery queries from Clearinghouse clients.