Forum: LTDP SAFE

Re: Re: EO Collection and EO Product metadata separation

Apparently this was not explicitly addressed in HMA. The way HMA links a product with the collection is via the parentIdentifier, whose cardinality is 0 to 1, so it does not allow for multiple collections unless some type is redefined. In the proposed SAFE structure it is feasible via the redefinition of the EOP type “EarthObservationMetadataType” to increase the cardinality of the parentIdentifier. The space for the EOP redefined types was already foreseen in our approach, so there is no change in the structure.

For the redefinition there are some options:
- First, removal of “parentIdentifier” by restriction, and after, addition of same “parentIdentifier” element with unbounded cardinality
- Extend “EarthObservationMetadataType“ with a different element “otherParentIdentifiers” with unbounded cardinality

Below there is a preliminary guess about the first option for the redefinition:

Current definition in EOP: eop.xsd

<xs:complexType name="eop:EarthObservationMetadataType">
 <xs:sequence>
  …
   <element name="parentIdentifier" type="string" minOccurs="0">
    <annotation>
      <documentation>Collection Identifier.
        </documentation>
    </annotation>
   </element>
  …
 </xs:sequence>
</xs:complexType>


Step 1) redefinition in SAFE (removes the current parentIdentifier): eop-safe1.xsd

<xs:redefine schemaLocation=”eop.xsd”>
 …
  <xs:complexType name="EarthObservationSAFEMetadataType">
   <xs:complexContent>
    <xs:restriction base="eop:EarthObservationSAFEMetadataType">
     <xs:sequence>
      … All elements except for parentIdentifier
     </xs:sequence>
    </xs:restriction>
   </xs:complexContent>
  </xs:complexType>
 …
</xs:redefine>

Step 2) redefinition in SAFE (adds a new parentIdentifier with the right cardinality): eop-safe.xsd


<xs:redefine schemaLocation=”eop-safe1.xsd”>
 …
  <xs:complexType name="EarthObservationSAFEMetadataType">
   <xs:complexContent>
    <xs:extension base="eop:EarthObservationSAFEMetadataType">
     <xs:sequence>
      <element name="parentIdentifier" type="string" minOccurs="0" maxOccurs="unbounded">
       <annotation>
        <documentation>Collection Identifier.
        </documentation>
       </annotation>
      </element>
     </xs:sequence>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 …
</xs:redefine>

Result) A valid portion of the XML instance would be as follows (replacing … by the right namespaces):


<...:metaDataProperty>
 <...:EarthObservationMetaData>
  <...:identifier>DS_PHR1A_20010822110247_TLS_PX_E123N45_0101_01234</...:identifier>
   <...:parentIdentifier>COLL_ID_1</...:parentIdentifier>
   <...:parentIdentifier>COLL_ID_2</...:parentIdentifier>
   <...:parentIdentifier>COLL_ID_3</...:parentIdentifier>
   <…:acquisitionType>NOMINAL</...:acquisitionType>
   <...:productType>TBD</...:productType>
   <...:status>ARCHIVED</...:status>
   <...:downlinkedTo>
    <...:DownlinkInformation>
     <...:acquisitionStation codeSpace="urn:...:PHR:stationCode">TLS</...:acquisitionStation>
    </...:DownlinkInformation>
   </...:downlinkedTo>
   <...:archivedIn>
    <...:ArchivingInformation>
     <...:archivingCenter codeSpace="urn:...:PHR:stationCode">TLS</...:archivingCenter>
     <...:archivingDate>2001-08-22T11:02:47.999</...:archivingDate>
    </...:ArchivingInformation>
   </...:archivedIn>
   <...:processing>
    <...:ProcessingInformation/>
   </...:processing>
  </...:EarthObservationMetaData>
 </...:metaDataProperty>


Regards,

Héctor.



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