+++ /dev/null
-# -*- coding: utf-8 -*-
-from xml.parsers.expat import ExpatError
-from datetime import date
-import time
-
-from librarian import ValidationError, NoDublinCore
-
-import lxml.etree as etree # ElementTree API using libxml2
-from lxml.etree import XMLSyntaxError
-
-
-# ==============
-# = Converters =
-# ==============
-class Person(object):
- """Single person with last name and a list of first names."""
- def __init__(self, last_name, *first_names):
- self.last_name = last_name
- self.first_names = first_names
-
- @classmethod
- def from_text(cls, text):
- parts = [ token.strip() for token in text.split(',') ]
- if len(parts) == 1:
- surname = parts[0]
- names = []
- elif len(parts) != 2:
- raise ValueError("Invalid person name. There should be at most one comma: \"%s\"." % text)
- else:
- surname = parts[0]
- if len(parts[1]) == 0:
- # there is no non-whitespace data after the comma
- raise ValueError("Found a comma, but no names given: \"%s\" -> %r." % (text, parts))
- names = [ name for name in parts[1].split() if len(name) ] # all non-whitespace tokens
- return cls(surname, *names)
-
- def __eq__(self, right):
- return self.last_name == right.last_name and self.first_names == right.first_names
-
-
- def __unicode__(self):
- if len(self.first_names) > 0:
- return '%s, %s' % (self.last_name, ' '.join(self.first_names))
- else:
- return self.last_name
-
- def __repr__(self):
- return 'Person(last_name=%r, first_names=*%r)' % (self.last_name, self.first_names)
-
-def as_date(text):
- try:
- try:
- t = time.strptime(text, '%Y-%m-%d')
- except ValueError:
- t = time.strptime(text, '%Y')
- return date(t[0], t[1], t[2])
- except ValueError, e:
- raise ValueError("Unrecognized date format. Try YYYY-MM-DD or YYYY.")
-
-def as_person(text):
- return Person.from_text(text)
-
-def as_unicode(text):
- if isinstance(text, unicode):
- return text
- else:
- return text.decode('utf-8')
-
-class Field(object):
- def __init__(self, uri, attr_name, type=as_unicode, multiple=False, salias=None, **kwargs):
- self.uri = uri
- self.name = attr_name
- self.validator = type
- 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):
- try:
- if self.multiple:
- if self.validator is None:
- return val
- return [ self.validator(v) if v is not None else v for v in val ]
- elif len(val) > 1:
- raise ValidationError("Mulitply 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:
- return val[0]
- return self.validator(val[0])
- except ValueError, e:
- raise ValidationError("Field '%s' - invald value: %s" % (self.uri, e.message))
-
- def validate(self, fdict):
- if not fdict.has_key(self.uri):
- if not self.required:
- f = self.default
- else:
- raise ValidationError("Required field %s not found" % self.uri)
- else:
- f = fdict[self.uri]
-
- return self.validate_value(f)
-
-# ==========
-# = Parser =
-# ==========
-
-class XMLNamespace(object):
- '''Represents XML namespace.'''
-
- def __init__(self, uri):
- self.uri = uri
-
- def __call__(self, tag):
- return '{%s}%s' % (self.uri, tag)
-
- def __contains__(self, tag):
- return tag.startswith(str(self))
-
- def __repr__(self):
- return 'XMLNamespace(%r)' % self.uri
-
- def __str__(self):
- return '%s' % self.uri
-
-
-class BookInfo(object):
- RDF = XMLNamespace('http://www.w3.org/1999/02/22-rdf-syntax-ns#')
- DC = XMLNamespace('http://purl.org/dc/elements/1.1/')
-
- FIELDS = (
- Field( DC('creator'), 'author', as_person),
- Field( DC('title'), 'title'),
- Field( DC('subject.period'), 'epoches', salias='epoch', multiple=True),
- Field( DC('subject.type'), 'kinds', salias='kind', multiple=True),
- Field( DC('subject.genre'), 'genres', salias='genre', multiple=True),
- Field( DC('date'), 'created_at', as_date),
- Field( DC('date.pd'), 'released_to_public_domain_at', as_date, required=False),
- Field( DC('contributor.editor'), 'editors', \
- as_person, salias='editor', multiple=True, default=[]),
- Field( DC('contributor.translator'), 'translators', \
- as_person, salias='translator', multiple=True, default=[]),
- Field( DC('contributor.technical_editor'), 'technical_editors',
- as_person, salias='technical_editor', multiple=True, default=[]),
- Field( DC('publisher'), 'publisher'),
- Field( DC('source'), 'source_name', required=False),
- Field( DC('source.URL'), 'source_url', required=False),
- Field( DC('identifier.url'), 'url'),
- Field( DC('relation.hasPart'), 'parts', multiple=True, required=False),
- Field( DC('rights.license'), 'license', required=False),
- Field( DC('rights'), 'license_description'),
- )
-
- @classmethod
- def from_string(cls, xml):
- from StringIO import StringIO
- return cls.from_file(StringIO(xml))
-
- @classmethod
- def from_file(cls, xmlfile):
- desc_tag = None
- try:
- iter = etree.iterparse(xmlfile, ['start', 'end'])
- for (event, element) in iter:
- if element.tag == cls.RDF('RDF') and event == 'start':
- desc_tag = element
- break
-
- if desc_tag is None:
- raise NoDublinCore("DublinCore section not found. \
- Check if there are rdf:RDF and rdf:Description tags.")
-
- # continue 'till the end of RDF section
- for (event, element) in iter:
- if element.tag == cls.RDF('RDF') and event == 'end':
- break
-
- # 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)
- except XMLSyntaxError, e:
- raise ParseError(e)
- except ExpatError, e:
- raise ParseError(e)
-
- @classmethod
- def from_element(cls, rdf_tag):
- # the tree is already parsed, so we don't need to worry about Expat errors
- field_dict = {}
- desc = rdf_tag.find(".//" + cls.RDF('Description') )
-
- if desc is None:
- raise NoDublinCore("No DublinCore section found.")
-
- for e in desc.getchildren():
- fv = field_dict.get(e.tag, [])
- fv.append(e.text)
- field_dict[e.tag] = fv
-
- return cls( desc.attrib, field_dict )
-
- def __init__(self, rdf_attrs, dc_fields):
- """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.about = rdf_attrs.get(self.RDF('about'))
- self.fmap = {}
-
- for field in self.FIELDS:
- value = field.validate( dc_fields )
- setattr(self, 'prop_' + field.name, value)
- self.fmap[field.name] = field
- if field.salias: self.fmap[field.salias] = field
-
- def __getattribute__(self, name):
- try:
- field = object.__getattribute__(self, 'fmap')[name]
- value = object.__getattribute__(self, 'prop_'+field.name)
- if field.name == name:
- return value
- else: # singular alias
- if not field.multiple:
- raise "OUCH!! for field %s" % name
-
- return value[0]
- except (KeyError, AttributeError):
- return object.__getattribute__(self, name)
-
- def __setattr__(self, name, newvalue):
- try:
- field = object.__getattribute__(self, 'fmap')[name]
- if field.name == name:
- object.__setattr__(self, 'prop_'+field.name, newvalue)
- else: # singular alias
- if not field.multiple:
- raise "OUCH! while setting field %s" % name
-
- object.__setattr__(self, 'prop_'+field.name, [newvalue])
- except (KeyError, AttributeError):
- return object.__setattr__(self, name, newvalue)
-
- def update(self, field_dict):
- """Update using field_dict. Verify correctness, but don't check if all
- required fields are present."""
- for field in self.FIELDS:
- if field_dict.has_key(field.name):
- setattr(self, field.name, field_dict[field.name])
-
- def to_etree(self, parent = None):
- """XML representation of this object."""
- #etree._namespace_map[str(self.RDF)] = 'rdf'
- #etree._namespace_map[str(self.DC)] = 'dc'
-
- if parent is None:
- root = etree.Element(self.RDF('RDF'))
- else:
- root = parent.makeelement(self.RDF('RDF'))
-
- description = etree.SubElement(root, self.RDF('Description'))
-
- if self.about:
- description.set(self.RDF('about'), self.about)
-
- for field in self.FIELDS:
- v = getattr(self, field.name, None)
- if v is not None:
- if field.multiple:
- if len(v) == 0: continue
- for x in v:
- e = etree.Element(field.uri)
- e.text = unicode(x)
- description.append(e)
- else:
- e = etree.Element(field.uri)
- e.text = unicode(v)
- description.append(e)
-
- return root
-
- def to_dict(self):
- result = {'about': self.about}
- for field in self.FIELDS:
- v = getattr(self, field.name, None)
-
- if v is not None:
- if field.multiple:
- if len(v) == 0: continue
- v = [ unicode(x) for x in v ]
- else:
- v = unicode(v)
- result[field.name] = v
-
- if field.salias:
- v = getattr(self, field.salias)
- if v is not None: result[field.salias] = v
-
- return result
-
-def parse(file_name):
- return BookInfo.from_file(file_name)
fnp / librarian.git / blobdiff