The official form of an ISBN is something like
ISBN 979-10-90636-07-1. However for most applications only the numbers are important and you can always masked them if you need (see below). This library works mainly with ‘striped’ ISBNs (only numbers and X) like ‘0826497527’. You can strip an ISBN’s like string by using
canonical(isbnlike). You can ‘mask’ the ISBN by using
mask(isbn). So in the examples below, when you see ‘isbn’ in the argument, it is a ‘striped’ ISBN, when the argument is an ‘isbnlike’ it is a string like
ISBN 979-10-90636-07-1or even something dirty like
asdf 979-10-90636-07-1 bla bla.
Two important concepts: valid ISBN should be an ISBN that was built according with the rules, this is distinct from issued ISBN that is an ISBN that was already issued to a publisher (this is the usage of the libraries and most of the web services). However isbn.org, probably by legal reasons, merges the two! So, according to isbn.org, ‘9786610326266’ is not valid (because the block 978-66… has not been issued yet, however if you use
is_isbn13('9786610326266')you will get
True(because ‘9786610326266’ follows the rules of an ISBN). But the situation is even murkier, try
meta('9786610326266')and you will see that this ISBN was already used!
If possible, work with ISBNs in the isbn-13 format (since 2007, only are issued ISBNs in the isbn-13 format). You can always convert isbn-10 to isbn-13, but not the reverse. Read more about ISBN at isbn-international.org.
API’s Main Namespaces¶
In the namespace
isbnlib you have access to the core methods:
- Validates as ISBN-10.
- Validates as ISBN-13.
- Transforms an isbn-13 to isbn-10.
- Transforms an isbn-10 to isbn-13.
- Keeps only numbers and X. You will get strings like 9780321534965.
- Cleans ISBN (only legal characters).
- Check with the goal to invalidate isbn-like.
- Extracts all substrings that seem like ISBNs (very useful for scraping).
- Extracts ISBNs and transform them to the canonical form.
- Transforms an isbnlike string into an EAN13 number (validated canonical ISBN-13).
- Gets the language or country assigned to this ISBN.
- Mask (hyphenate) a canonical ISBN.
meta(isbn, service='default', cache='default')
- Gives you the main metadata associated with the ISBN. As service parameter you can use:
'goob'uses the Google Books service (no key is needed) and is the default option,
'openl'uses the OpenLibrary.org api (no key is needed). You can enter API keys with
config.add_apikey(service, apikey)(see example below). The output can be formatted as
json(BibJSON) bibliographic formats with
cacheonly allows two values: ‘default’ or None. You can change the kind of cache by using
isbnlib.registry.set_cache(see below). Now, you can extend the functionality of this function by adding pluggins, more metadata providers or new bibliographic formatters (check for available pluggins).
- Returns the list of ISBNs of editions related with this ISBN. By default uses ‘merge’ (merges ‘openl’ and ‘thingl’), but other providers are available: ‘openl’ users Open Library, ‘thingl’ (uses the service ThingISBN from LibraryThing) and ‘any’ (first tries ‘openl’, if no data, then ‘thingl’).
- Returns the most probable ISBN from a list of words (for your geographic area).
- Returns a list of references from Google Books multiple references.
- Returns a DOI’s ISBN-A from a ISBN-13.
- Returns metadata formated as BibTeX for a given DOI.
- Renames a file using metadata from an ISBN in his filename.
- Returns a small description of the book. Almost all data available are for US books!
- Returns a dictionary with the url for cover. Almost all data available are for US books!
The exceptions raised by these methods can all be catched using
You can extend the lib by using the classes and functions exposed in
WEBServicea class that handles the access to web services (just by passing an url) and supports
gzip. You can subclass it to extend the functionality… but probably you don’t need to use it! It is used in the next class.
WEBQuerya class that uses
WEBServiceto retrieve and parse data from a web service. You can build a new provider of metadata by subclassing this class. His main methods allow passing custom functions (handlers) that specialize them to specific needs (
parser). It implements a throttling mechanism with a default rate of one call per second per service.
Metadataa class that structures, cleans and ‘validates’ records of metadata. His method
mergeallows to implement a simple merging procedure for records from different sources. The main features can be implemented by a call to
viasexposes several functions to put calls to services, just by passing the name and a pointer to the service’s
vias.parallelallows to put threaded calls. You can use
vias.serialto make serial calls and
vias.multito use several cores. The default is
vias.serial, but you can change that in the conf file.
The exceptions raised by these methods can all be catched using
You should’t raise this exception in your code, only raise the specific exceptions
isbnlib.dev whose name end in Error.
isbnlib.dev.helpers you can find several methods, that we found very useful, some of then
are only used in
isbntools (an app and framework that uses
isbnlib.registry you can change the metadata service to be used by default (
add a new service (
add_service), access bibliographic formatters for metadata (
set the default formatter (
setdefaultbibformatter), add new formatters (
set a new cache (
set_cache) (e.g. to switch off the chache
The cache only works for calls through
isbnlib.meta. These changes only work for the ‘current session’,
so should be done always before calling other methods.
isbnlib.config you can read and set configuration options:
change timeouts with
access api keys with
apikeys and add new one with
access and set generic and user-defined options with
Let us concretize the last point with a small example.
Suppose you want a small script to get metadata using
Open Library formated in BibTeX.
A minimal script would be:
from isbnlib import meta from isbnlib.registry import bibformatters SERVICE = 'openl' # now you can use the service isbn = '9780446310789' bibtex = bibformatters['bibtex'] print(bibtex(meta(isbn, SERVICE)))
All these classes follow a simple design pattern and, if you follow it, will be very easy to integrate your classes with the rest of the lib.
You can extend the functionality of the library by adding pluggins (for now, just new metadata providers or new bibliographic formatters).
After install, your pluggin will blend transparently in
Remember that plugins must support python 2.7 and python 3.4+ (see python-future.org).
For available pluggins check here.
To get extra functionality, search pypi for packages starting with
or type at a terminal:
$ pip search isbnlib
for a nice formated report!
The original quality of metadata, at the several services, is not very good!
If you need high quality metadata in your app, the only solution is to use
polling & merge of several providers and a lot of cleaning and standardization
for fields like
A simple merge provider is now the default in
It gives priority to
wcat but overwrites the
fields with values from
goob (if available) or
merge method of
Metadata and parallel calls to services.
You can change that by using
vias’s other methods
You can write your own merging scheme by creating a new provider (see
merge for an example).
These classes are optimized for one-calls to services and not for batch calls.