figure out how to implement OpenURL

[simon]

current plan: use crossref's OpenURL resolver for implementing COinS and CrossRef's OpenURL resolver (<a href="​http://www.crossref.org/02publishers/openurl_info.html">here</a>) for journals. still working on what to do for books. use google? use amazon? use LOC?

[simon]

(In [425]) addresses #83, figure out how to implement OpenURL

Scholar.OpenURL.resolve(item) returns the URL that retrieves an item from the user's OpenURL resolver. this means we can implement a "find in my library" feature.
Scholar.OpenURL.discoverResolvers() returns a list of available resolvers for the user's current location (by IP address).

[simon]

(In [426]) addresses #83, figure out how to implement OpenURL

adds preliminary support for COinS microformat data. does not yet support COinS where there is only a DOI or ISBN.

[simon]

(In [428]) addresses #83, figure out how to implement OpenURL

OpenURL lookup now works for books. this means that all that's necessary to add scrapable book metadata to a page is an ISBN, as shown below:

<span class="Z3988" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info:ofi/fmt:kev:mtx:book&amp;rft.isbn=1579550088"></span>

also, we can now scrape Open WorldCat and Wikipedia Book Sources pages with no specialized code involved.

i'm still looking for a better way of looking up journal article metadata. it's currently implemented with CrossRef, but CrossRef simply will not work without a DOI, and is also incomplete (only holds the last name of the first author).

[simon]

(In [430]) closes #83, figure out how to implement OpenURL
closes #76, implement extensible search/retrieval architecture for obtaining metadata

OpenURL COinS lookup is now implemented using a real search architecture system. at the moment, it works with Open WorldCat for books, CrossRef for journal articles (provided the COinS object contains a DOI or an ISSN), and PubMed when a PMID is available.