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Provides information about an NDR object.

This request is currently under development, and is subject to change at any time. It is not considered one of the core NDR API methods. If possible, use get instead

Request URL[handle]
where [handle] is a handle for an NDR object.
May be an HTTP GET or POST request.


(the Handle is at the end of the requestURL)

Response Fields

  • handle – the NDR handle for the object.
  • properties – these include:
    • label - Contains the name of the type of object (e.g. Resource, Metadata)
    • createdDate - the date the object was created, in UTC (GMT).
    • lastModifiedDate - the date the object last modified, in UTC (GMT).
    • state - the state of the object, per Fedora: Active or Deleted
  • relationships – all the relationships this object participates in. Each relationship has:
    • type - indicates the type of relationship (e.g. "memberOf", "metadataFor")
    • target - an identifier for the thing this object relates TO. If the relationship is between two NDR objects, this identifier will be an NDR handle. If it is a relationship between the object and a resource URL, then this identifier will be a URL. If the relationship describes the objectType, then this identifier will be an object type (e.g. "Resource" or "Metadata"). It could also be a handle for the "hasHandle" relationship, an OAI id for the "itemId" relationship, etc.
    • url (Optional) - if the identifier is an NDR handle, then this is the URL for a "describe" request of that NDR object.
Types of relationships (not an exhaustive list):
    • objectType - this relationship's target is one of the NDR object types "Resource", "Metadata," etc. (see ObjectTypes)
    • itemId - the target is the OAI identifier for this object, to be used in OAI views of the NDR.
    • hasHandle - Resource and Agent objects may have handles; the target is the handle for the object.
    • hasResourceURL - Resource objects have a normalized URL, which is the target of this relationship.
    • uniqueId - Metadata objects have a unique identifier for the contained metadata, which is supplied by their metadataProvider.
    • setSpec - the OAI setSpec for an aggregation's exposure as an OAI set. (see
    • setSpecName - a short, human-readable name for the OAI set.
    • memberOf - this object is a member of an aggregation; the target is the handle for the Aggregator object.
    • hasMetadata - the target object contains metadata describing this object (or what this object represents in the NDR, such as a resource)
    • metadataFor - this object contains metadata describing the target object (or what the target object represents in the NDR, such as a resource).
    • metadataProvidedBy - target MetadataProvider object provided the metadata in this object.
    • metadataProviderFor - target Agent object is the attributable source for any metadata provided by this object.
    • aggregatedBy - target is the Aggregator object describing the aggregation relevant to this object.
    • aggregatorFor - target is the Agent object attributable for any aggregation provided by this object.
    • representedBy - target is the Resource object that will represent an actual aggregation (grouping) of objects.
    • hasAggregator - target is an Aggregator object representing an aggregation attributable to this (Agent) object.
    • hasMetadataProvider - - target is a MetadataProvider object representing provided metadata attributable to this (Agent) object.
  • data – information about the data stored with this object. In Fedora parlance, these are the datastreams. Each data item has:
    • id - Datastream identifier
    • url - URL for the datastream contents. Points to a get request that fetches datastream content

Types of datastreams (not an exhaustive list):

    • content - Contains the digital content of a Resource. Examples of resource content may include HTML web pages, PDF documents, XML files, images, and videos.
    • serviceDescription - Aggregator and MetadataProvider objects require information to be associated with the service, such as dublin core metadata, contact imformation, branding, etc.
    • format_xyz - Contains metadata in a given format 'xyz'. Examples of formats include nsdl_dc and oai_dc.
    • format_zyz_info, Information about metadata in format xyz. Is used internally to create the OAI "about".
    • metadata Not a true datastream, it represents individual units of metadata that describe a given object. For example, if executing a describe request on a resource, the metadata items refer to the content of each Metadata object that is metadataFor that resource.

Response Examples

for a Resource object: 2200/20060614134957422T (see also below)
for a Metadata object:
for a MetadataProvider object:
for an Aggregator object:
for an Agent object:
response for a describe request for a Resource object
<?xml version="1.0" encoding="UTF-8"?>
<NSDLRepository schemaVersion="1.00.000"
<nsdl_dc:nsdl_dc xmlns:dc="" xmlns:dct="" xmlns:ieee="" xmlns:nsdl_dc="" xmlns:xsi="" schemaVersion="1.02.000" xsi:schemaLocation="">
<dc:title>Michigan Teacher Network</dc:title>
<dc:subject>Technology--Study and teaching</dc:subject>
<dc:subject>Mathematics--Study and teaching</dc:subject>
<dc:subject>Michigan; schools; teacher; educational technology; clearinghouse; curriculum; classroom; lesson plans; pedagogy; k-12; best practices; reviews; learning; teaching; professional development; Michigan Curriculum Framework; standards; technology plan; computers; education index</dc:subject>
<dc:subject>Science--Study and teaching</dc:subject>
<dc:subject xsi:type="dct:LCSH">Educational technology</dc:subject>
<dc:subject xsi:type="dct:LCSH">Curriculum planning</dc:subject>
<dc:subject xsi:type="dct:LCSH">Curriculum</dc:subject>
<dc:subject xsi:type="nsdl_dc:GEM">Instructional issues</dc:subject>
<dc:description>Michigan Teacher Network supports Michigan K-12 educators in the successful use of technology by providing best practice, professional development, and evaluated curriculum resources. Curriculum materials are correlated to Michigan Curriculum Framework content standards.</dc:description>
<dc:publisher>Merit Network Inc.</dc:publisher>
<dc:contributor>Center to Support Technology in Education; Kate Pittsley; Ellen Hoffman; Betty Van Dam</dc:contributor>
<dc:type xsi:type="dct:DCMIType">Collection</dc:type>
<dc:format xsi:type="dct:IMT">text/html</dc:format>
<dc:format xsi:type="dct:IMT">image</dc:format>
<dc:identifier xsi:type="dct:URI"></dc:identifier>
<dc:language xsi:type="dct:RFC3066">en</dc:language>
<dct:educationLevel xsi:type="nsdl_dc:NSDLEdLevel">Grades Pre-K to 12</dct:educationLevel>

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