On January 14, 2019, the Foundations for Evidence-Based Policymaking Act ("Evidence Act"), which includes the OPEN Government Data Act, was signed into law. The Evidence Act requires the Office of Management and Budget, the Office of Government Information Services, and the General Services Administration to develop and maintain an online repository of tools, best practices, and schema standards to facilitate the adoption of open data practices across the Federal Government. When the new repository is launched, it will replace and retire Project Open Data. Check back here for updates.

Metadata Changelog

This page lists changes to the Project Open Data metadata schema by version. Latest changes at the top. Consult repository history for explanations.

Changelog

Version 1.1

Final as of 11/6/2014

Changes made to establish the v1.1 Schema

Catalog Required Fields
  • Adds required conformsTo field to specify the schema version (#309)
  • Adds required dataset field as a container for all datasets listed (#309)
  • Adds optional describedBy field to specify a canonical or customized JSON schema file (#309, #332)
  • Adds optional @context field to specify a JSON-LD Context (#338)
  • Adds optional @id field to specify a JSON-LD Node Identifier (#338)
  • Adds optional @type field to specify a JSON-LD data type (#338)
Dataset Required Fields
  • Changes contactPoint field to an object that contains the name (fn) and email address (hasEmail) (#358)
    • Adds fn field as part of contactPoint replacing earlier use of contactPoint (#358)
    • Renames mbox field to hasEmail and moves to within contactPoint (#358)
  • Changes publisher field to an object that allows multiple levels of organizations (#296)
    • Adds name as part of publisher replacing earlier use of publisher (#296)
    • Adds optional subOrganizationOf field as part of publisher to include parent organization hierarchy (#296)
  • Adds optional @type field to specify a JSON-LD data type (#338)
  • Recommends that identifier uses a URL, but does not require it. (#69)
Dataset Required-if-Applicable Fields
  • Removes webService field. APIs can be described within a distribution using accessURL and format (#291)
  • Renames accessLevelComment field to rights (#353)
  • Changes license field to be a URL (196)
  • Changes distribution field to become required-if-applicable and to always contain the accessURL or downloadURL fields (#217)
Dataset Distribution Fields
  • Adds required-if-applicable downloadURL field to replace earlier use of accessURL and to exist as a field within distribution (#335)
  • Adds required-if-applicable mediaType field to replace earlier use of format and to exist as a field within distribution (#272)
  • Changes accessURL field to represent indirect access and to exist only as an optional field within distribution (#217, #335)
  • Changes format field to a human readable description and to exist only as an optional field within distribution (#272, #293)
  • Adds optional description field for use within distribution (#248)
  • Adds optional title field for use within distribution (#248)
  • Adds optional describedBy field to specify a distribution specific data dictionary (#291, #332)
  • Adds optional describedByType field to specify the format of the data dictionary referenced with describedBy (#291, #332)
  • Adds optional conformsTo field to specify a standard the distribution conforms to (#362)
  • Adds optional @type field to specify a JSON-LD data type (#338)
Expanded Fields
  • Changes accrualPeriodicity field to use ISO 8601 date syntax (#292)
  • Renames PrimaryITInvestmentUII field to primaryITInvestmentUII to use capitalization consistent with the rest of the schema (#284)
  • Renames dataDictionary field to describedBy (#291, #332)
  • Adds optional describedByType field (#291, #332)
  • Adds optional conformsTo field to specify a standard the dataset conforms to (#362)
  • Adds optional isPartOf field to group datasets as a collection (#258)

Version 1.0 FINAL - 9/20/2013

Changes made to establish the v1.0 Schema

“Common Core” Required Fields
  • Aligns modified field to ISO 8601 of least resolution
  • Adds required bureauCode field
  • Adds required programOffice field
  • Renames person field to contactPoint to better align with DCAT
  • Changes the keywords field to an array
“Common Core” Required-if-Applicable Fields
  • Adds required-if-applicable accessLevelComment field
  • Aligns format field to MIME types
  • Aligns temporal field to ISO 8601 of least resolution
  • Changes temporal field to use solidus for date ranges
Expanded Fields
  • Aligns accrualPeriodicity field to DCCDAccrualPeriodicity
  • Aligns issued field to ISO 8601 of least resolution
  • Aligns language field to RFC 5646
  • Changes the language field to an array
  • Removes granularity field
  • Removes size field
  • Removes feed field