In that case, you might also try ISBN search via Z39.50, and ask for an OPAC record to be returned. The call number comes back in a very predictable place, so it might be less trouble than screen scraping, and easier to adapt to different target libraries.
-Tod > On Nov 29, 2021, at 10:50 AM, M Belvadi <mbelv...@gmail.com> wrote: > > Thank you all. I perhaps should have clarified that I am NOT trying to get > a dump of a library's entire holdings. I just want to look for LC Call > numbers for a few specific ISBNs, if they own that book with an LC call > number. > So I don't need the entire MARC record, and a dump would be incredibly > inefficient and almost always out of date, as often the books I'm looking > for are fairly new. > > I am already using OCLC's Classify service, and I always check that first > before trying any other site, but I find that that only has about 19 out of > 20 that I look for, and when I look for the rest manually on various opacs, > including UC's, I can often find about 50% of the missing ones. So I'm just > trying to do that programmatically with BeautifulSoup. I am also using > Harvard's API as second choice to the ones that OCLC misses, but that > almost never has the ones that OCLC didn't have, so I need more places to > look and those are the only public APIs I've been able to find that have > any chance of providing LC Calll Numbers (eg openlibrary and google apis > have other metadata but not call numbers). > > FYI, it seems to me that the new UC Library Search, when limited to the > catalog which is what I want, is Alma underneath. > > And further FYI, the reason I'm doing this is I'm attempting to write a > python program that can take a COUNTER R5 book report and add to it LC call > numbers to make it easier for librarians looking especially at the B1 (use) > and B2 (turnaways) data to be able to quickly group the usage by "subject" > since no kind of subject classification is included in the COUNTER standard. > > When I have it completed, I will share it freely on Github, so I want to > make sure I'm doing nothing furtive, but only touching servers whose owners > wouldn't be upset to find themselves included in my code. > > Melissa Belvadi > mbelv...@gmail.com > > > On Mon, Nov 29, 2021 at 9:23 AM Eric Lease Morgan <emor...@nd.edu> wrote: > >> On Nov 28, 2021, at 6:01 AM, Peter Velikonja <pe...@koios.co> wrote: >> >>> As Kyle mentioned, a screenscraping method is inefficient and will >>> get you incomplete results. As a vendor to public libraries, I routinely >>> request (and receive) MARC dumps. Some libraries are better than >>> others at pulling these from their ILS, but records based on MARC come >>> from the Library of Congress and are therefore public information -- to >>> which you are entitled if you reside in the US. A number of libraries >>> make dumps available through various Open Data initiatives -- spotty but >>> can be useful. Screenscraping can be good for spot-checking, but if >>> you want a complete catalog, working with an ILS administrator is, in >>> my view, a better path. >> >> >> I concur. See if you can get an MARC dump. If you are seeking the >> bibliographic information, then this probably the most complete, accurate, >> and efficient. --Eric Morgan >>