Use Case 15: Preview Dataset (metadata driven)

From Federation of Earth Science Information Partners


Use Case EIE15: Preview Dataset (Metadata driven)

for

ESIP Earth Information Exchange


Version 1.0 draft

Prepared by Karl Benedict

Earth Data Analysis Center, University of New Mexico

December 12, 2005



1.Use Case Identification

1.1.Use Case Number

EIE15

1.2.Use Case Name

Provide a preview of a dataset (collection) through information provided in the metadata for that dataset.

2.Use Case Definition

This use case represents the presentation of a preview of a collection of data grandules in order to help a system user determine if the dataset is appropriate for their needs. This preview may include a depiction of the spatial domain for the dataset and a sample representation of a component dataset granule.

2.1.Actors

User

2.2.Preconditions

  • 1.Metadata for a dataset is registered into the portal
  • 2.The provided metadata includes: sufficient spatial domain information to depict the spatial domain in a reference map, and, a link to a preview image of a granule associated with the dataset.
  • 3.The user has identified a dataset for which they would like more information, including a preview.

2.3.Postconditions

  • 1.A window is presented to the user that provides the preview information

2.4.Normal Flow

  • EIE15.0.1) User is presented with a listing of datasets to that meet specified criteria (EIE09)
  • EIE15.0.2) If preview information is provided for the dataset, a link to the preview is provided in the dataset listing.
  • EIE15.0.3) The user clicks the 'preview' link in the portal
  • EIE15.0.4) The preview for the selected dataset is opened, with a default display of the spatial extent of the datasets and a link to a preview image representing one granule of the dataset. (EIE16)

2.5.Alternative Flows

No preview information is included in the dataset metadata:

  • EIE15.1.1) User is presented with a listing of datasets that meet specified criteria (EIE09)
  • EIE15.1.2) When inadequare preview information is provided in dataset metadata, no link to such a service will be provided
  • EIE15.1.3) No preview functionality is enabled for this dataset.

2.6.Exceptions

  • 1.The preview extent information provided in the metadata is not a valid set of values for depicting the mapped extent. Display an error to the user and log the event.
  • 2.The granule preview associated with the dataset is not referenced by a valid URL. Display an error message to the user, log the event, and return the user to the preview page.

2.7.Extension Points

  • 1.EIE16 – Preview Granule

2.8.Priority

Moderate

2.9.Frequency of Use

Invoked several times per session

2.10.Business Rules

None

2.11.Special Requirements

The granule preview should be based upon a quick-response interface that does not incur high processing or network latency costs.

2.12.Assumptions

A standard representation of spatial extents is encoded into dataset metadata.

2.13.Notes and Issues

Though presented as optional, it seems that there should be a minimum requirement that spatial extent be encoded into dataset metadata, but this is probably another point of discussion in how to enable this capability.

Are there other dataset preview capabilities that we want/need?