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inefficient and almost always out of date, as often the books I'm looking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
[log in to unmask]


On Mon, Nov 29, 2021 at 9:23 AM Eric Lease Morgan <[log in to unmask]> wrote:

> On Nov 28, 2021, at 6:01 AM, Peter Velikonja <[log in to unmask]> 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
>