Add publication date property to keywordSet

[mbjones]

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Author Name: ben leinfelder (ben leinfelder)
Original Redmine Issue: 5998, https://projects.ecoinformatics.org/ecoinfo/issues/5998
Original Date: 2013-06-06
Original Assignee: Matt Jones

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From Éamonn Ó Tuama [GBIF] eotuama@gbif.org:

Both EML and ISO19115 provide fields for keywords and the name/title of associated thesaurus. However, if the thesaurus name is provided, in the case, of ISO19115, a publication date must also be included. In order to ensure maximum information transfer in cross walks from EML to the new North American Profile of ISO19115 [1], consider adding a conditional date (and date type) property to the EML keywordSet. See example in [2].

[1] http://nap.geogratis.gc.ca/metadata/napMetadata-eng.html
[2] http://nap.geogratis.gc.ca/metadata/examples/napEx1.xml

[mbjones]

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Original Redmine Comment
Author Name: Matt Jones (Matt Jones)
Original Date: 2013-06-06T18:16:32Z

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An example excerpt of an ISO document showing how this is used is shown here for reference:

<gmd:descriptiveKeywords>
    <gmd:MD_Keywords>
        <gmd:keyword xsi:type="PT_FreeText_PropertyType">
            <gco:CharacterString>NESTS</gco:CharacterString>
            <PT_FreeText>
                <textGroup>
                    <LocalisedCharacterString locale="#locale_fra_CAN">NIDS</LocalisedCharacterString>
                </textGroup>
            </PT_FreeText>
        </gmd:keyword>
        <gmd:type>
            <gmd:MD_KeywordTypeCode codeList="http://nap.geogratis.gc.ca/metadata/register/napMetadataRegister.xml#IC_110" codeListValue="RI_528">theme</gmd:MD_KeywordTypeCode>
        </gmd:type>
        <gmd:thesaurusName>
            <gmd:CI_Citation>
                <gmd:title>
                    <gco:CharacterString>
                        Ontario Ministry of Natural Resources (OMNR) Thesaurus
                    </gco:CharacterString>
                </gmd:title>
                <gmd:date>
                    <gmd:CI_Date>
                        <gmd:date>
                            <gco:Date>1972-06-22</gco:Date>
                        </gmd:date>
                        <gmd:dateType>
                            <gmd:CI_DateTypeCode codeList="http://nap.geogratis.gc.ca/metadata/register/napMetadataRegister.xml#IC_87" codeListValue="RI_366">creation</gmd:CI_DateTypeCode>
                        </gmd:dateType>
                    </gmd:CI_Date>
                </gmd:date>
                <gmd:date>
                    <gmd:CI_Date>
                        <gmd:date>
                            <gco:Date>2006-07-16</gco:Date>
                        </gmd:date>
                        <gmd:dateType>
                            <gmd:CI_DateTypeCode codeList="http://nap.geogratis.gc.ca/metadata/register/napMetadataRegister.xml#IC_87" codeListValue="RI_368">revision</gmd:CI_DateTypeCode>
                        </gmd:dateType>
                    </gmd:CI_Date>
                </gmd:date>
                <gmd:edition>
                    <gco:CharacterString>
                        Originally created to catalogue documents stored in the OMNR library and since modified
                    </gco:CharacterString>
                </gmd:edition>
                <gmd:citedResponsibleParty>
                    <gmd:CI_ResponsibleParty>
                        <gmd:organisationName>
                            <gco:CharacterString>Ministry of Natural Resources</gco:CharacterString>
                        </gmd:organisationName>
                        <gmd:role>
                            <gmd:CI_RoleCode codeList="http://nap.geogratis.gc.ca/metadata/register/napMetadataRegister.xml#IC_90" codeListValue="RI_414">pointOfContact</gmd:CI_RoleCode>
                        </gmd:role>
                    </gmd:CI_ResponsibleParty>
                </gmd:citedResponsibleParty>
            </gmd:CI_Citation>
        </gmd:thesaurusName>
    </gmd:MD_Keywords>
</gmd:descriptiveKeywords>

[mbjones]

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Original Redmine Comment
Author Name: Matt Jones (Matt Jones)
Original Date: 2013-12-11T19:02:40Z

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Two questions:

1. Looking at this example more closely, rather than just a date, I wonder if it would make sense to add an optional 'citation' field for the thesaurus, which would closely mirror the CI_Citation provided in ISO.

2. In general we prefer adding optional fields as they allow for easy forward transformations from older EML versions to new. However, if this information is optional, then the conversion to ISO won't be valid when the field is omitted. So, which is more important, backwards compatibility with EML, or ISO validity?