src/docbkx/guid-resolution.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <chapter version="5.0" xml:id="guid-resolution"
   3          xmlns="http://docbook.org/ns/docbook"
   4          xmlns:ns5="http://www.w3.org/1999/xhtml"
   5          xmlns:ns4="http://www.w3.org/2000/svg"
   6          xmlns:ns3="http://www.w3.org/1998/Math/MathML"
   7          xmlns:ns2="http://www.w3.org/1999/xlink"
   8          xmlns:ns="http://docbook.org/ns/docbook">
   9   <info>
  10     <title>Globally Unique Identifier Resolution</title>
  11   </info>
  12
  13   <section>
  14     <caution>
  15       <title>Likely To Change</title>
  16
  17       <para>Globally unique identifiers, their use and implementation are
  18       still an unresolved topic. The implementaton of objects that are
  19       identifiable and resolvable in a global sense must, given an open world,
  20       reflect the standards and best practices being used by the community as
  21       a whole. Consequently this area of the CDM is likely to change to
  22       reflect this.</para>
  23     </caution>
  24
  25     <para>The service layer implements a number of services designed to serve
  26     as the basis of a LSID Resolution Service. This includes implementations
  27     of <interfacename>LSIDAuthorityService</interfacename>,
  28     <interfacename>LSIDMetadataService</interfacename>, and
  29     <interfacename>LSIDDataService</interfacename>. Note that these are
  30     service-layer implementations - the http-specific components can be found
  31     in the <package>cdmlib-remote</package> package.</para>
  32
  33     <para>In addition to implementations of the three core LSID Resolution
  34     services, the service layer holds the
  35     <interfacename>LSIDRegistry</interfacename>, the component that maps LSID
  36     authority + namespace combinations onto CDM classes. The implementation
  37     assumes that a given authority and namespace will map onto a single CDM
  38     base class, but that authorities may use different namespaces for the same
  39     class of objects. In addition, the
  40     <interfacename>LSIDRegistry</interfacename> provides a way of controlling
  41     which authority + namespace combinations a CDM application will respond
  42     to. For example, it is possible that an application will store objects
  43     with identifiers published by another (foreign) authority, but doesn't
  44     wish to serve metadata about these objects. By only registering specific
  45     authority + namespace combinations in the
  46     <interfacename>LSIDRegistry</interfacename>, a CDM store can resolve some
  47     combinations but not others.</para>
  48
  49     <para>The three most common methods used are the
  50     <methodname>getAuthorityWSDL</methodname> and
  51     <methodname>getAvailableServices</methodname> methods that return a
  52     <interfacename>javax.xml.transform.Source</interfacename> within an
  53     <interfacename>ExpiringResponse</interfacename> object suitable for
  54     rendering in a response to a client, and
  55     <methodname>getMetadata</methodname>, that returns an
  56     <interfacename>IIdentifiableEntity</interfacename> within a
  57     <interfacename>MetadataResponse</interfacename>. If the
  58     authority+namespace is not resolved, or if the object cannot be resolved,
  59     or if the client requests metadata in an unavailable format, an exception
  60     is thrown.</para>
  61   </section>
  62 </chapter>