from datetime import date
import time
-from librarian import ValidationError, NoDublinCore, ParseError, DCNS, RDFNS
+from librarian import (ValidationError, NoDublinCore, ParseError, DCNS, RDFNS,
+ WLURI)
import lxml.etree as etree # ElementTree API using libxml2
from lxml.etree import XMLSyntaxError
else:
return text.decode('utf-8')
+def as_wluri_strict(text):
+ return WLURI.strict(text)
+
class Field(object):
- def __init__(self, uri, attr_name, type=as_unicode, multiple=False, salias=None, **kwargs):
+ def __init__(self, uri, attr_name, validator=as_unicode, strict=None, multiple=False, salias=None, **kwargs):
self.uri = uri
self.name = attr_name
- self.validator = type
+ self.validator = validator
+ self.strict = strict
self.multiple = multiple
self.salias = salias
self.required = kwargs.get('required', True) and not kwargs.has_key('default')
self.default = kwargs.get('default', [] if multiple else [None])
- def validate_value(self, val):
+ def validate_value(self, val, strict=False):
+ if strict and self.strict is not None:
+ validator = self.strict
+ else:
+ validator = self.validator
try:
if self.multiple:
- if self.validator is None:
+ if validator is None:
return val
- return [ self.validator(v) if v is not None else v for v in val ]
+ return [ validator(v) if v is not None else v for v in val ]
elif len(val) > 1:
raise ValidationError("Multiple values not allowed for field '%s'" % self.uri)
elif len(val) == 0:
raise ValidationError("Field %s has no value to assign. Check your defaults." % self.uri)
else:
- if self.validator is None or val[0] is None:
+ if validator is None or val[0] is None:
return val[0]
- return self.validator(val[0])
+ return validator(val[0])
except ValueError, e:
raise ValidationError("Field '%s' - invald value: %s" % (self.uri, e.message))
- def validate(self, fdict):
+ def validate(self, fdict, fallbacks=None, strict=False):
+ if fallbacks is None:
+ fallbacks = {}
if not fdict.has_key(self.uri):
if not self.required:
- f = self.default
+ # Accept single value for single fields and saliases.
+ if self.name in fallbacks:
+ if self.multiple:
+ f = fallbacks[self.name]
+ else:
+ f = [fallbacks[self.name]]
+ elif self.salias and self.salias in fallbacks:
+ f = [fallbacks[self.salias]]
+ else:
+ f = self.default
else:
raise ValidationError("Required field %s not found" % self.uri)
else:
f = fdict[self.uri]
- return self.validate_value(f)
+ return self.validate_value(f, strict=strict)
+
+ def __eq__(self, other):
+ if isinstance(other, Field) and other.name == self.name:
+ return True
+ return False
+
+class DCInfo(type):
+ def __new__(meta, classname, bases, class_dict):
+ fields = list(class_dict['FIELDS'])
+ for base in bases[::-1]:
+ if hasattr(base, 'FIELDS'):
+ for field in base.FIELDS[::-1]:
+ try:
+ fields.index(field)
+ except ValueError:
+ fields.insert(0, field)
+ class_dict['FIELDS'] = tuple(fields)
+ return super(DCInfo, meta).__new__(meta, classname, bases, class_dict)
+
+
+class WorkInfo(object):
+ __metaclass__ = DCInfo
-class BookInfo(object):
FIELDS = (
- Field( DCNS('creator'), 'author', as_person),
+ Field( DCNS('creator'), 'authors', as_person, salias='author', multiple=True),
Field( DCNS('title'), 'title'),
- Field( DCNS('subject.period'), 'epochs', salias='epoch', multiple=True),
- Field( DCNS('subject.type'), 'kinds', salias='kind', multiple=True),
- Field( DCNS('subject.genre'), 'genres', salias='genre', multiple=True),
- Field( DCNS('audience'), 'audiences', salias='audience', multiple=True,
- required=False),
- Field( DCNS('date'), 'created_at', as_date),
- Field( DCNS('date.pd'), 'released_to_public_domain_at', as_date, required=False),
+ Field( DCNS('type'), 'type', required=False, multiple=True),
+
Field( DCNS('contributor.editor'), 'editors', \
as_person, salias='editor', multiple=True, default=[]),
- Field( DCNS('contributor.translator'), 'translators', \
- as_person, salias='translator', multiple=True, default=[]),
Field( DCNS('contributor.technical_editor'), 'technical_editors',
as_person, salias='technical_editor', multiple=True, default=[]),
+
+ Field( DCNS('date'), 'created_at', as_date),
+ Field( DCNS('date.pd'), 'released_to_public_domain_at', as_date, required=False),
Field( DCNS('publisher'), 'publisher'),
+
+ Field( DCNS('language'), 'language'),
+ Field( DCNS('description'), 'description', required=False),
+
Field( DCNS('source'), 'source_name', required=False),
Field( DCNS('source.URL'), 'source_url', required=False),
- Field( DCNS('identifier.url'), 'url'),
- Field( DCNS('relation.hasPart'), 'parts', multiple=True, required=False),
+ Field( DCNS('identifier.url'), 'url', WLURI, strict=as_wluri_strict),
Field( DCNS('rights.license'), 'license', required=False),
Field( DCNS('rights'), 'license_description'),
- Field( DCNS('language'), 'language'),
- Field( DCNS('description'), 'description', required=False),
)
- @property
- def slug(self):
- return self.url.rsplit('/', 1)[1]
-
@classmethod
- def from_string(cls, xml):
+ def from_string(cls, xml, *args, **kwargs):
from StringIO import StringIO
- return cls.from_file(StringIO(xml))
+ return cls.from_file(StringIO(xml), *args, **kwargs)
@classmethod
- def from_file(cls, xmlfile):
+ def from_file(cls, xmlfile, *args, **kwargs):
desc_tag = None
try:
iter = etree.iterparse(xmlfile, ['start', 'end'])
# if there is no end, Expat should yell at us with an ExpatError
# extract data from the element and make the info
- return cls.from_element(desc_tag)
+ return cls.from_element(desc_tag, *args, **kwargs)
except XMLSyntaxError, e:
raise ParseError(e)
except ExpatError, e:
raise ParseError(e)
@classmethod
- def from_element(cls, rdf_tag):
+ def from_element(cls, rdf_tag, *args, **kwargs):
# the tree is already parsed, so we don't need to worry about Expat errors
field_dict = {}
- desc = rdf_tag.find(".//" + RDFNS('Description') )
+ desc = rdf_tag.find(".//" + RDFNS('Description'))
if desc is None:
raise NoDublinCore("No DublinCore section found.")
fv.append(e.text)
field_dict[e.tag] = fv
- return cls( desc.attrib, field_dict )
+ return cls(desc.attrib, field_dict, *args, **kwargs)
- def __init__(self, rdf_attrs, dc_fields):
+ def __init__(self, rdf_attrs, dc_fields, fallbacks=None, strict=False):
"""rdf_attrs should be a dictionary-like object with any attributes of the RDF:Description.
dc_fields - dictionary mapping DC fields (with namespace) to list of text values for the
given field. """
self.fmap = {}
for field in self.FIELDS:
- value = field.validate( dc_fields )
+ value = field.validate(dc_fields, fallbacks=fallbacks,
+ strict=strict)
setattr(self, 'prop_' + field.name, value)
self.fmap[field.name] = field
if field.salias: self.fmap[field.salias] = field
if not field.multiple:
raise "OUCH!! for field %s" % name
- return value[0]
+ return value[0] if value else None
except (KeyError, AttributeError):
return object.__getattribute__(self, name)
return root
-
def serialize(self):
rdf = {}
rdf['about'] = { 'uri': RDFNS('about'), 'value': self.about }
return result
-def parse(file_name):
- return BookInfo.from_file(file_name)
+
+class BookInfo(WorkInfo):
+ FIELDS = (
+ Field( DCNS('audience'), 'audiences', salias='audience', multiple=True,
+ required=False),
+
+ Field( DCNS('subject.period'), 'epochs', salias='epoch', multiple=True,
+ required=False),
+ Field( DCNS('subject.type'), 'kinds', salias='kind', multiple=True,
+ required=False),
+ Field( DCNS('subject.genre'), 'genres', salias='genre', multiple=True,
+ required=False),
+
+ Field( DCNS('contributor.translator'), 'translators', \
+ as_person, salias='translator', multiple=True, default=[]),
+ Field( DCNS('relation.hasPart'), 'parts',
+ WLURI, strict=as_wluri_strict, multiple=True, required=False),
+ Field( DCNS('relation.isVariantOf'), 'variant_of',
+ WLURI, strict=as_wluri_strict, required=False),
+
+ Field( DCNS('relation.coverImage.url'), 'cover_url', required=False),
+ Field( DCNS('relation.coverImage.attribution'), 'cover_by', required=False),
+ Field( DCNS('relation.coverImage.source'), 'cover_source', required=False),
+ )
+
+
+def parse(file_name, cls=BookInfo):
+ return cls.from_file(file_name)