MDTranslator ISO19115-2 to DCATUS: License

[Jin-Sun-tts]

User Story

In order to transform ISO19115-2 documents into DCATUS using mdtranslator, datagov wants to add processing for license

Acceptance Criteria

• GIVEN the DCATUS license field
  AND how the DCATUS writer expects to find the data within the internal metadata object
  WHEN the associated ISO19115-2 reader ruby modules are created
  THEN license should be transformed from ISO19115-2 to DCATUS

Background

• related to #4862
• We process 291017 ISO19115-2 datasets. We want all our datasets to be in DCATUS.
• This reader is not intended to be feature complete according to the ISO19115-2 standard. All we're looking to read is as much as the DCATUS writer expects.
• ISO19115-3 development workflow

Security Considerations (required)

None

Sketch

• field mapping relationship ISO19115-2 -> MDJSON -> DCATUS
  • .//gmd:MD_DataIdentification//gmd:resourceConstraints//gmd:MD_Constraints//gmd:useLimitation
  • intObj[:metadata][:resourceInfo][:constraints][:reference][:title]
  • license
• add processing in resourceInfo to read keywords from gmd:MD_DataIdentification
• create a transformation test demonstrating how the value went from the ISO19115-2 document into the DCATUS json
• create a response object message test verifying when required elements are missing

[rshewitt]

iso19115-3 has 3 constraints: common, legal, and security. if these are present in -2 then you should probably create all 3. reference in the constraint is a citation in -3. dcatus only pulls the title from that reference/citation so there shouldn't need to be an update to the citation module because title is already processed

[Jin-Sun-tts]

In the current DCAT-US writer, the license is derived from resourceInfo -> constraints -> reference -> title.

ISO19115-3 
<mri:resourceConstraints>
    <mco:MD_Constraints>
           <mco:reference>
               <cit:CI_Citation>
                  <cit:title>

However, in ISO19115-2, MD_Constraints under resourceConstraints does not include a reference element.

 <gmi:MI_Metadata
   <gmd:identificationInfo>
     <gmd:MD_DataIdentification>
       <gmd:resourceConstraints> 
          <gmd:MD_Constraints>
             <gmd:useLimitation>

need guidance on how to locate the corresponding license information in ISO19115-2.

[btylerburton]

Based on this statement from https://resources.data.gov/resources/podm-field-mapping/:

license | License | if applicable | no | default value for government data is ‘Public Domain’

and the default field for DCAT-US in the writer which is:

license = title || 'https://creativecommons.org/publicdomain/zero/1.0/'

https://github.com/GSA/mdTranslator/blob/datagov/lib/adiwg/mdtranslator/writers/dcat_us/sections/dcat_us_license.rb#L10

I believe our current ckanext-spatial transformer treats the rights and license fields interchangeably, and incorrectly.

In https://catalog.data.gov/dataset/office-of-coast-survey-wrecks-and-obstructions-database / https://catalog.data.gov/harvest/object/f5060a92-e297-4940-b8f3-41ed6eb39a34 the <gmd:useLimitation> should be mapped to rights and not license.

I'm closing this with the expectation that no further work is needed to make this spec compliant, though changes might be necessary to adapt it to our needs when we reach that step.

[btylerburton]

I'm going to write a test case for this even if we don't have any code changes and we will defer to the default from the writer.