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The Content datastream provides access to the primary data/content available from a Resource.

exactly one
Found in 
Binary content or URL redirect

Usage and Semantics

The Content datastream provides a consistent and predictable address for accessing resource contents. It represents an abstraction of the details of actual content location - content may or may not physically reside in the repository. Since datastreams are accessed via HTTP, the Content datastream may issue a redirect containing the true address of the content location, lost likely offsite.

There is a integrity constraint placed between the Content datastream and the hasResourceURL property in the same object, namely that the content accessible at the URL specified in hasResourceURL MUST be identical to the content accessible via the Content datastream. In a practical sense, that means that if the Content stream issues a redirect, it redirects to the location specified in hasResourceURL. Likewise, if the Content stream does not issue a redirect, then the hasResourceURL URL MUST be the URL of the Content datastream. When creating or modifying a resource, it is not necessary to specify or populate both Content and hasResourceURL - changes to one will automatically be reflected in the other. For example, in creating a new resource that represents redirected content, it is only necessary to specify hasResourceURL. A compliant Content datastream will automatically be created. Likewise, in creating a resource containing primary content, it is only necessary to specify the contents of the Content datastream. The hasResourceURL property will be automatically created and populated.

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