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This document contains several PURL examples. It is assumed that you are familiar PURLs and just want to see them in action. If you have any problems or questions, please feel free contact the PURL Team.
http://purl.oclc.org/keith/home
This is a PURL. If you follow the link, you should contact the OCLC PURL Service to resolve the PURL and get a redirect to my current home page.
http://purl.oclc.org/OCLC/PURL/summary
This is another PURL. If you follow the link, you should retrieve a brief summary of why we built the OCLC PURL Service.
http://purl.oclc.org/keith/test1
This PURL has had it's resolution turned off by it's owner (me). By following the link, you will get an information page about the PURL instead of a redirect to an actual item. Note that the page contains no URL in the current, but does contain a valid link in the history section.
http://purl.oclc.org/fake/not-in-the-db
It is still possible to get a standard 404 Document not Found message from a PURL Service. For instance, the URL above does not exist in the PURL database at OCLC and there is no document at the PURL Resolver site that corresponds to it. Therefore, if you follow the link, you should get a 404 message. This is the correct HTTP response since our resolver is also serving documents directly.
You can clearly see that the URL in the previous paragraph is not in the PURL database by issuing a service display request like http://purl.oclc.org/service/display/fake/not-in-the-db. Note that this does not return a 404 message as it is directly querying the PURL database.
PURLs can be passed in as parameters to service requests. For instance, you might want to search our PURL database for information about a PURL. This is different from requesting the resolution of a PURL. While many of our services are only available via forms, the following examples show that some are also directly available as HTTP GETs.
http://purl.oclc.org/SERVICE/DISPLAY/keith/home
This is a service display request for my home page. By following the link, you should get information about the PURL for my home page, not my home page itself.
http://purl.oclc.org/SERVICE/DISPLAY/http://purl.oclc.org/keith/home
This is another service display request for my home page. Note that this request contains the complete PURL. Eventually, we'd like to service requests on PURLs that are not directly located in our database.
http://purl.oclc.org/net/service/display/InterCat
This is a service display request that shows the history of a PURL that has changed a lot. Particularly, it's a nice example of PURL resolution being used to switch from a test server to production server without affecting end users.
The concept of partial redirection is the use of a domain as a prefix for a localized hierarchy of URLs. This is possible because a PURL resolver will resolve as much of a PURL as it can find in its database and append the remainder (unresolved portion) to the end of the resolved URL. Using this concept, you could create a partial redirect as the permanent name prefix for all the resources stored at a web site or any hierarchical subset thereof. For example, if the partial redirect "http://purl.foo.com/bar" exists and is associated with the URL http://your.web.server/web/root, then an attempt to resolve the partial redirect PURL http://purl.foo.com/bar/some/other/stuff.html will resolve to the URL http://your.web.server/web/root/some/other/stuff.html.
http://purl.oclc.org/keith/home/visiting.html
This is a request for a document available via the partial redirect entry in our PURL database for http://purl.oclc.org/keith/home/.
Using a service display requests to search our PURL database, we can view the partial redirect entry for http://purl.oclc.org/keith/home/ and see that there is NO entry in our PURL database for http://purl.oclc.org/keith/home/visiting.html.
CNRI has a URN scheme based on Handles. PURL servers can resolve Handles that have associated URLs. For instance, to read about CNRI and Handles, go to the CNRI home page: http://purl.oclc.org/hdl/cnri-1/cnri_home. Note that this actually a PURL resolution of the Handle cnri-1/cnri_home.