Upgrade Guide for converting Metadata from GBL 1.0 to OGM Aardvark

The following options are two ways to upgrade GBL 1.0 metadata into OGM Aardvark. The figures include references to Solr, the search index that powers a GeoBlacklight instance.

Option 1: New pipeline

Re-run the metadata pipeline with a new crosswalk

Fig.1 - Metadata pipeline showing a conversion from standards metadata

Scenario

• you have geospatial resources with structured metadata files in an official standard, such as ISO 19139, FGDC, MODS, or MARC
• your organization already has a metadata pipeline process that converts these structured files to GBL 1.0

How does it work?

This option involves updating your local transformation workflow that extracts values from standards-based metadata files.

• For institutions that utilize an XSLT for the transformation, the GeoCombine repository has XSL files.

• For institutions that use custom tools or Python scripts, refer to the OGM Aardvark - FGDC- ISO 19139 crosswalk to update the code.

Considerations for Option #1

• This may require extra institutional support, particularly if the transformation process is part of a larger framework or connected to a repository.
• The community-developed XSLs are still a work in progress.

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Option 2: Convert JSONs

Programmatically convert the JSON files

Fig.2 - Programmatic transformation process using GeoBlacklight 1.0 Metadata JSONs

Scenarios

• you only have GBL 1.0 metadata (no structured metadata files in an official standard)
• you want to test your environment with the new Aardvark schema

How does it work?

1. Gather GBL 1.0 metadata JSON files on your desktop
2. Use a script or tool to batch convert GBL 1.0 JSON files to OGM Aardvark
3. Re-index the resulting Aardvark JSON files into your application (GeoBlacklight)

Currently, the OpenGeoMetadata community has two tools that can do batch conversions:

• gbl2aardvark: A web-hosted interface (recommended tool).

  • Users can upload GBL 1.0 metadata files to this tool and it will return a downloadable JSON in the OGM Aardvark schema.
  • In addition to direct crosswalks, this tool will populate the Resource Class and Resource Type based upon the Type and Geometry Type fields from version 1.0. It will also generate new collection level records based upon the value in the Is Part Of fields.
  • Any fields that do not properly convert will be flagged with the phrase "EDIT ME --"
  • When reindexing Solr with a single JSON file representing multiple records, use Solr's "Document Type"="File Upload" option.
  • See the GitHub documentation for more information

• a standalone Python script: https://github.com/OpenGeoMetadata/gbl-1_to_aardvark.

  • This command line script will perform a straight conversion of field names.
  • It features an editable crosswalk file to customize the transformation.
  • The non-crosswalkable elements listed above (Type, Geometry Type, and Is Part Of) will be copied as-is into the new Aardvark JSONs.

Recommended: manually remediate transformed JSONs

Fig.3 - Transformation process that includes manual remediation

You may need to perform additional manual cleanup on the transformed JSONs.

1. Convert your metadata files to a CSV. This Python script will convert a batch of JSONs to a CSV file

2. Manually augment and adjust column names and values using spreadsheet functions.

3. Convert your spreadsheet to OGM Aardvark JSONs. This Python script will convert CSVs to Aardvark JSONS

Considerations for Option #2

• This can be a workaround method if changing the metadata pipeline is not feasible. However, it may result in incomplete metadata.

• It will not include some fields that are new in OGM Aardvark, such as Rights or License. To take advantage of those fields, use Option 1 or perform additional remediation.

• Manual cleanup after transformation may be labor intensive.