Advancing Access to Earth Science and Climate Data and Services Using RESTful Web Services from NASA’s Global Change Master Directory (GCMD)
NASA’s Global Change Master Directory (GCMD) has deployed RESTFul web services that provide “dynamic query access” to GCMD’s Earth science metadata collection and keywords. The Keyword Management Service (KMS) introduces a completely new paradigm for the use and management of the keywords (science keywords, service keywords, platforms, instruments, data centers, locations, projects, etc.) and allows access to the keywords in SKOS/RDF, OWL, XML, and CSV formats. The Metadata Web Service (MWS) provides a machine-to-machine interface for validating, publishing, and retrieving Earth science metadata (data set descriptions, service descriptions, ancillary descriptions, keywords, etc.) with the GCMD.
This session provides an overview of the GCMD web services, demonstrates their functionality, and explains how the community can utilize the web services for advancing access to Earth science and climate data and services. In addition, various data centers will demonstrate how they are using the GCMD web services.
Outline:
I. Introduction to the GCMD
II. Keyword Management System (KMS)
III. Metadata Web Service (MWS)
IV. User Demonstrations of KMS and MWS Use
V. Discussion
Below I tried to capture any questions asked during the meeting and any commentary that veered from the presentation flow. IMO no need to take detailed notes since you can just browse the presentations for details. A few Slide notes were added so people will have some idea of where during the presentation were the questions asked.
From Tyler's presentation:
Slide 8: details on keyword hierarchy
Slide 9: 20 year keyword accumulation
Q: How active is the process of keyword set modifications?
A: Couple times a year. science coordinators with specializations evaluate. Keyword sets are being evaluated now: e.g. for atmospheric science: work with DAACs, Remote Sensing specialists
Slide 11: RESTful web services for access implemented
Slide 13: question...
Q: Contents have changed?
A: There is a stewardship process, many keywords don't change, but some can change on weekly basis. Thomas: new platforms and instruments added as needed. Structure will not change but typos, wording tweaks etc happen
Q: Why does this service require authentication?
A: POST requests
Q: Why not use HTTPS?
A: Cost and admin preferences. Agreed HTTPS is a good idea. Cost of an SSL cert is not an issue like it was when Verisign pretty much had a monopoly (Tommy comment added post-meeting).
Q: Why not open up GET APIs?
A: Thomas: yes, planning on it. Slide 15 (continuity point) Switch to Thomas' presentation and demo here... Slide 4: URL to connect to GCMD: gcmd.nasa.gov/Connect/
Q: How do you know the entry id?
A: Service assumes you know what it is, and query language which is documented on Connect page PDF Thomas commentary: queries audience on choice for scripting interface? He suggests JavaScript, audience suggested Python. Thomas demoed iPad app to walk keyword hierarchy to leaf node.
Q: User reg comment: utilize GIOVANNI single signon
A: Already using ESDIS Bruce Vollmer talk: Use GCMD as metadata repository
Q: Can you show example of DOI and where does it live?
A: GES DISC landing page URL Plug: any more questions on DOIs? Attend poster session.
Suggestion: use jQuery for developing single page app.
Q: Is services code shareable?
A: No, hidden.
Commentary: Suggestion to use throttling to avoid the DOS attack flagging issue.
| Attachment | Size |
|---|---|
 esip demo[1].pdf | 154.36 KB |
| GCMD_ESIP_WINTER_2013.pdf | 1.14 MB |
| GES DISC ESIP Winter 2013.pdf | 809.33 KB |
Comments
Questions asked and comments made during the session.
Notes/Comments added to main page (with proper formatting)