1: This is a pilot release of the NSDL-LONCAPA Gateway.
3: The goal
5: Implement a metadata exchange of resources from
6: NSDL (http://www.smete.org) to LON-CAPA (http://www.lon-capa.org)
7: and vice versa.
9: More information is in the doc/ directory.
11: What's new
13: For a history of this software, you should work through
14: the CVS repository.
16: export CVSROOT=:pserver:USERNAME@install.lon-capa.org:/home/cvs
17: cvs login
18: cvs co nsdl
20: How to build and install
23: cd nsdl/build
24: make build
25: make install
27: Important files
29: The stylesheets for carrying out the metadata conversion are
30: nsdl/lib/stylesheets/*.xsl .
32: The Apache web handler modules are defined in the directory:
33: nsdl/lib/perl/Apache/ .
35: The Apache configuration file (see below also) is
36: nsdl/conf/nsdl.conf .
38: The source-to-target is defined by nsdl/build/gatewayfiles.lpml
39: (an XML file defines how the software is "rendered" onto the system).
41: And, there are other files.
43: System requirements
45: * Apache and mod_perl
46: * Graham Barr's TimeDate module (http://search.cpan.org/search?dist=TimeDate)
47: * XML::Xalan perl module (http://search.cpan.org/search?dist=XML-Xalan)
49: To configure your machine, you will need to add the following
50: line to your /etc/httpd/conf/httpd.conf file.
52: Include conf/nsdl.conf
54: (You will then need to restart your web server;
55: /etc/rc.d/init.d/httpd restart)
59: This is a pilot effort. The goal was to enact a reasonable
60: solution and directly uncover difficult issues.
62: Here are some of the remaining issues
63: * ISSUE: User authentication
64: PROBLEM: users are crossing domains, so browser-cookie validation can't work
65: SUGGESTED SOLUTIONS: should require a GPG public key and/or
66: servers should communicate to coordinate passing of user
67: and/or some kind of proxy or central verification system
68: * ISSUE: Imperfect metadata cross-walking
69: PROBLEM: There are a range of imperfect mappings between Dublin Core and
70: LON-CAPA metadata fields as well as between IEEE LOM and LON-CAPA
71: metadata fields.
72: SUGGESTED SOLUTIONS: Improve the LON-CAPA metadata that is collected and
73: place more importance on the exhaustive IEEE LOM
74: standard rather than the weaker Dublin Core standard.
75: In the future, to get to Dublin Core, it might make
76: sense to convert LON-CAPA to IEEE LOM and *then*
77: go to IEEE LOM metadata standard.
78: * ISSUE: Set hierarchies
79: PROBLEM: Asking for ListIdentifiers from LON-CAPA will return a really long
80: list that represents a "jumbled" repository. Currently,
81: ListIdentifiers, ListRecords, etc return error messages--
82: we do not yet support set hierarchy results.
83: SUGGESTED SOLUTIONS: authors should be able to nominate their records
84: for being part of a meaningful collection of academic
85: resources; thus multiple OAI-distributed metadata sets
86: would actually be contained within LON-CAPA
87: * ISSUE: Code thoroughness
88: PROBLEM: Limited time. I had limited time (100 hours) to enact a gateway.
89: SUGGESTED SOLUTIONS: Invest more time. The API and documentation
90: could be a better match for what is implemented
91: and vice versa.
92: * ISSUE: Making SMETE available to LON-CAPA
93: PROBLEM: Ummm... I thought SMETE supported OAI. The only interface I find
94: is enriched HTML forms.
95: SUGGESTED SOLUTIONS: SMETE should support OAI or some exporting of XML files
96: in Dublin Core or IEEE LOM or whatever they are using.
100: Scott Harrison, 2002