Importing BIBCAT and Overview of Functions

Written by Jeremy Nelson on 2017-10-30

Importing BIBCAT

To import BIBCAT, first activate your Virtual Environment and then launch the Python IDLE program with this command (bibcat-env) $ python -m idlelib.


Python 3.6.0 (v3.6.0:41df79263a11, Dec 23 2016, 08:06:12) [MSC v.1900 64 bit (AMD64)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> import bibcat
INFO:rdflib:RDFLib Version: 4.2.2
>>> bibcat.__version__
'1.18.1'

Setup for Exercises

Before we explore bibcat, we'll create a minimal RDF environment to use through-out this tutorial.

Import rdflib module
```
>>> import rdflib
```

Create a BIBFRAME 2.0 Namespace BF

>>> BF = rdflib.Namespace("http://id.loc.gov/ontologies/bibframe/")

Create a test RDF graph
```
>>> test_graph = bibcat.rdflib.Graph()
```

BIND BIBFRAME namespace in graph

>>> test_graph.namespace_manager.bind("bf", BF)

Overview of BIBCAT Functions

The base bibcat module has a number of helpful RDF functions when building Semantic Web and Linked Data applications

_is_valid_uri, clean_uris, create_rdf_list

The bibcat._is_valid_uri function is used internally by other functions in the base bibcat module. This function uses rdflib internal functions for validating URIs.


>>> bibcat._is_valid_uri("http://bibcat.org/")
True
>>> bibcat._is_valid_uri("http://bibcat.org/ ")
False
>>>

The bibcat.clean_uris function is used in post-processing the RDF produced by the Library of Congress's marc2bibframe2 XSLT process which sometimes includes URIs that are invalid and cause errors when trying to process further with either bibcat.rml.processor or bibcat.linkers classes.

The bibcat.create_rdf_list function creates a RDF List that preserves the order of the elements in RDF. Many of the complex subjects that result from the MARC XML-to-BIBFRAME 2.0 marc2bibframe2 XSLT transform.

delete_bnode, delete_iri, replace_iri

The delete_bnode, delete_iri, and replace_iri helper functions are used by multiple bibcat submodules. These helper functions allow for easier manipulation of RDF Graphs to link-out and replace local instances of a RDF entity with a linked URI that exists locally or through an external linking entity like the Library of Congress or Geonames.

slugify and wikify

The bibcat.slugify and bibcat.wikify allow you to create human-readable but valid URIs for use in your Linked Data applications.

The bibcat.slugify function takes a string, lowercases all characters, replaces spaces with dashes, and removes any punctuation.


>>> bibcat.slugify("A short message.")
'a-short-message'
>>> bibcat.slugify("A Very Long Title by Dr. First name Second name")
'a-very-long-title-by-dr-first-name-second-name'

The bibcat.wikify is similar function but converts a string that follows [Wikipedia][https://en.wikipedia.org/wiki/Main_Page] patter of keeping capitalization and replacing punctuation and spaces with underscores.


>>> bibcat.wikify("A short message.")
'A_short_message'
>>> bibcat.wikify("A Very Long Title by Dr. First name Second name")
'A_Very_Long_Title_by_Dr_First_name_Second_name'

Now that we have had a quick overview of some of the base bibcat functions, we'll next use the Library of Congress marc2bibframe2 to transform MARC XML records to BIBFRAME 2.0 RDF XML.