OAITMPlugin

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OAI TM Plugin is a plugin of the Tree Based Access Facilities that allows harvesting of metadata descriptions of the records in an archive, using The Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH).

Each OAI Record is transformed in a edge-labelled tree by OAI TM Plugin.

Plugin parameters fields

Plugins lead to the creation of one or more collections. Thus, in addition to the information below, the user should specify collection name and description.

In order to instruct a Plugin on how to perform the harvesting, a user should specify the following mandatory information:

  • repository name: the name of the repository to be harvested, e.g. "aquacomm";
  • base URL: the base URL of the repository, e.g. "http://aquacomm.fcla.edu/cgi/oai2";
  • default metadata format: the metadata format to be used for harvesting, e.g. "oai_dc";
  • title XPath: the expression for identifying the title of the harvested resource, e.g. "//*[local-name()='title']";

In addition to that, the user might specify the following information:

  • content XPath: the expression for identifying the content of the harvested resource, e.g. "//*[local-name()='identifier' and contains(.,'://')]";
  • alternatives XPath: the expression for identifying additional content of the harvested resource, e.g. "//*[local-name()='relation' and contains(.,'://')]";
  • set Identifiers List: the list of id of the sets to take into consideration during the harvesting phase;

Two typologies of plugins have been defined:

  • WrapSetsRequest: to create a collection for each set of the external repository or for each set specified in the setIdentifierList;
  • WrapRepositoryRequest: to create a single collection containing the whole content of the repository or the content of the sets specified in the setIdentifierList;

Tree model

Conceptual Schema

Each collection item produced by this plugin is characterised by the following information:

  • item metadata: global information on the item including
    • title: the title of the record;
    • collectionID: the collection this item belongs to;
    • creationTime: the time the item was created;
    • lastUpdateTime: the most recent time the item has been updated;
    • provenance: It is characterised by the following information:
      • statement: "This item has been created by the gCube "+ pluginName +" via OAI-PMH metadata harvesting from the metadata provider "+repositoryName+" at "+baseURL;
      • setID: the repository set the object belongs to (optional and repeatable);
      • recordID: the identifier of the metadata record;
  • metadata (repeatable): the metadata record harvested. It is characterised by the following information:
    • schema: the metadata format of the metadata record;
    • schemaLocation: the metadata format schema URI;
    • record: the manifestation of the metadata record harvested;
  • content (repeatable): any potential payload shipped with the metadata record. It is characterised by the following information:
    • contentType: i.e. whether main or alternative content;
    • mimeType: MIME type of the actual content;
    • url: URL to the actual content;

XML Schema

The XML Schema of "record" element depends on the schema used to define record formats. This is a XML Schema of record in "oai_dc" metadataFormat.

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified" >
       <xs:element name="t:root" >
              <xs:complexType>
                     <xs:sequence>
                            <xs:element name="title" type="xs:string" />
                            <xs:element name="collectionID" type="xs:string" />
                            <xs:element name="creationTime" type="xs:string" />
                            <xs:element name="lastUpdateTime" type="xs:string" />
                            <xs:element name="provenance" >
                                   <xs:complexType>
                                          <xs:sequence>
                                                 <xs:element name="statement" type="xs:string" />
                                                 <xs:element name="setID" type="xs:string" maxOccurs="unbounded" />
                                                 <xs:element name="recordID" type="xs:string" />
                                             </xs:sequence>
                                      </xs:complexType>
                               </xs:element>
                            <xs:element name="metadata" >
                                   <xs:complexType>
                                          <xs:sequence>
                                                 <xs:element name="schema" type="xs:string" />
                                                 <xs:element name="schemaLocation" type="xs:string" />
                                                  	<xsd:element name="record">
								<xsd:complexType>
								  <xsd:sequence>
								    <xs:element name="oai_dc:dc" >
                                                                             <xs:complexType>
                                                                                    <xs:sequence>
                                                                                           <xs:element name="dc:title" type="xs:string" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:creator" maxOccurs="unbounded" type="xs:string" />
                                                                                           <xs:element name="dc:subject" maxOccurs="unbounded" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:description" type="xs:string" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:publisher" type="xs:string" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:contributor" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:date" type="xs:date" />
                                                                                           <xs:element name="dc:type" maxOccurs="unbounded" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:format" type="xs:string" />
                                                                                           <xs:element name="dc:identifier" type="xs:string" />
                                                                                           <xs:element name="dc:source" type="xs:string" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:language" type="xs:string" />
                                                                                           <xs:element name="dc:relation" type="xs:string" />
                                                                                           <xs:element name="dc:coverage" maxOccurs="unbounded" >
                                                                                                  <xs:complexType>
                                                                                                         <xs:attribute name="xml:lang" type="xs:string" />
                                                                                                     </xs:complexType>
                                                                                              </xs:element>
                                                                                           <xs:element name="dc:rights" type="xs:string" />
                                                                                       </xs:sequence>
                                                                                    <xs:attribute name="xmlns:oai_dc" type="xs:string" />
                                                                                    <xs:attribute name="xmlns:xsi" type="xs:string" />
                                                                                    <xs:attribute name="xmlns:dc" type="xs:string" />
                                                                                    <xs:attribute name="xsi:schemaLocation" type="xs:string" />
                                                                                </xs:complexType>
                                                                         </xs:element>
								  </xsd:sequence>
								</xsd:complexType>
						      </xsd:element>
                                             </xs:sequence>
                                      </xs:complexType>
                               </xs:element>
                            <xs:element name="content" maxOccurs="unbounded" minOccurs="0">
                                   <xs:complexType>
                                          <xs:sequence>
                                                 <xs:element name="contentType" type="xs:string" />
                                                 <xs:element name="mimeType" type="xs:string" />
                                                 <xs:element name="url" type="xs:string" />
                                             </xs:sequence>
                                      </xs:complexType>
                               </xs:element>
                        </xs:sequence>
                     <xs:attribute name="xmlns:t" type="xs:string" />
                     <xs:attribute name="t:id" type="xs:string" />
                 </xs:complexType>
          </xs:element>
   </xs:schema>

Example

A tree generated by OAI TM Plugin looks like the XML code below. The original record is available at this link: aquaticcommons.org/cgi/oai2.

<?xml version="1.0" ?>
<t:root xmlns:t="http://gcube-system.org/namespaces/data/trees"
	t:id="oai:generic.eprints.org:359" t:source="7374617475733D756E707562">
	<title>Association patterns and social dynamics of killer whales
		(Orcinus orca) in Greater Puget Sound</title>
	<collectionID>7374617475733D756E707562</collectionID>
	<creationTime>2011-09-29T22:10:02.000+02:00</creationTime>
	<lastUpdateTime>2011-09-29T22:10:02.000+02:00</lastUpdateTime>
	<provenance>
		<statement>This item has been created by the gCube OAI-TM plugin via
			OAI-PMH metadata harvesting from the metadata provider aquacomm at
			http://aquacomm.fcla.edu/cgi/oai2</statement>
		<setID>7374617475733D756E707562</setID>
		<setID>7375626A656374733D48</setID>
		<setID>7375626A656374733D44</setID>
		<setID>74797065733D746865736973</setID>
		<recordID>oai:generic.eprints.org:359</recordID>
	</provenance>
	<metadata>
		<schema></schema>
		<schemaLocation>http://www.openarchives.org/OAI/2.0/oai_dc/
		</schemaLocation>
		<record>
			<oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
				xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
				xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
				<dc:title xmlns:dc="http://purl.org/dc/elements/1.1/">Association patterns and social dynamics of killer whales (Orcinus orca) in Greater 
				Puget Sound</dc:title>
				<dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/">Heimlich-Boran, Sara Lou</dc:creator>
				<dc:subject xmlns:dc="http://purl.org/dc/elements/1.1/">Ecology</dc:subject>
				<dc:subject xmlns:dc="http://purl.org/dc/elements/1.1/">Biology</dc:subject>
				<dc:description xmlns:dc="http://purl.org/dc/elements/1.1/">Killer whales were observed in the inland marine waters of 
				Washington and British Columbia from March to November 1982 and January to November 1983. 
				The majority of the research occurred in Haro Strait in the San Juan Islands.  
				All whales were individually identifiable from naturally occurring marks and scars on the dorsal fin and back. 
				Many whales were identified visually in the field with the aid of a photographic guide to individuals (Biggs et al. 1987).  
				Seventy-two whales comprised the study population.  Data collection concentrated on group composition and spacing, 
				identification and associations of all whales present, and the recording of the dominant behavior occurring at that time. 
				Behaviors were categorized from combinations of quantifiable parameters of group composition, spacing of individuals, 
				speed and direction of travel, and the occurrence of specific behaviors such as leaps, tail slaps, penile erections, etc. (Osborne 1986).  
				Behaviors were pooled into four major groups: feeding, travel, rest and social/sexual behaviors. 
				The results suggest the following hypothesis about the social organization of the killer whales resident to Greater Puget Sound.  
				As a whale ages, it moves from an integrated position within the community, based on its relationship with its mother to a less 
				integrated period during adolescence in which social ties remain primarily through the older female generation.  
				With full adulthood, dependency upon these “allo-mothers” (N.J. Haenel 1986) declines and direct affiliation with the mothers 
				are re-established.  Adult whales remain with the maternal sub-group. Close associations between adult whales appear to be based 
				on relationship between direct kin.  Fission from the main material sub-group and the establishment of separate subgroups may be 
				the result of several factors including the age of the older female and the number, ages, and sex of her offspring, including adult sons. 
				 When older females die out, siblings or cousins may separate more permanently, forming new lineages or pods.</dc:description>
				<dc:date xmlns:dc="http://purl.org/dc/elements/1.1/">1988</dc:date>
				<dc:type xmlns:dc="http://purl.org/dc/elements/1.1/">Thesis</dc:type>
				<dc:type xmlns:dc="http://purl.org/dc/elements/1.1/">NonPeerReviewed</dc:type>
				<dc:format xmlns:dc="http://purl.org/dc/elements/1.1/">application/pdf</dc:format>
				<dc:identifier xmlns:dc="http://purl.org/dc/elements/1.1/">http://aquaticcommons.org/359/1/MS_Thesis_Social_Dynamics_Killer_Whales_Puget_Sound_1988.pdf</dc:identifier>
				<dc:identifier xmlns:dc="http://purl.org/dc/elements/1.1/">Heimlich-Boran, Sara Lou (1988) Association patterns and social dynamics of 
				killer whales (Orcinus orca) in Greater Puget Sound. Masters thesis, San Jose State University.</dc:identifier>
				<dc:relation xmlns:dc="http://purl.org/dc/elements/1.1/">http://aquaticcommons.org/359/</dc:relation>
			</oai_dc:dc>
		</record>
	</metadata>
	<content>
		<contentType>main</contentType>
		<mimeType>text/url</mimeType>
		<url>http://aquaticcommons.org/359/1/MS_Thesis_Social_Dynamics_Killer_Whales_Puget_Sound_1988.pdf
		</url>
	</content>
	<content>
		<contentType>alternative</contentType>
		<mimeType>text/html; charset=UTF-8</mimeType>
		<url>http://aquaticcommons.org/359/</url>
	</content>
</t:root>

Maven coordinates

The Maven coordinates of oai-tree-plugin of its development versions are:

<dependency>
  <groupId>org.gcube.data.oai.tmplugin</groupId>
  <artifactId>oai-tm-plugin</artifactId>
  <version>1.2.0-SNAPSHOT</version>
</dependency>

The oai-harvester library is available here:

<dependency>
  <groupId>org.gcube.common</groupId>
  <artifactId>oaiharvester</artifactId>
  <version>1.1.0</version>
</dependency>