default cover

[librarian.git] / librarian / dcparser.py

diff --git a/librarian/dcparser.py b/librarian/dcparser.py
index eb6c5ea..5a571ec 100644 (file)
--- a/librarian/dcparser.py
+++ b/librarian/dcparser.py
@@ -7,7 +7,8 @@ from xml.parsers.expat import ExpatError
 from datetime import date
 import time
 
 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
 
 import lxml.etree as etree # ElementTree API using libxml2
 from lxml.etree import XMLSyntaxError


@@ -78,35 +79,43 @@ def as_unicode(text):
     else:
         return text.decode('utf-8')
 
     else:
         return text.decode('utf-8')
 

+def as_wluri_strict(text):
+    return WLURI.strict(text)
+

 class Field(object):
 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.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])
 
         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:
         try:
             if self.multiple:

-                if self.validator is None:
+                if validator is None:

                     return val
                     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:
             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 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))
 
         except ValueError, e:
             raise ValidationError("Field '%s' - invald value: %s" % (self.uri, e.message))
 

-    def validate(self, fdict):
+    def validate(self, fdict, strict=False):

         if not fdict.has_key(self.uri):
             if not self.required:
                 f = self.default
         if not fdict.has_key(self.uri):
             if not self.required:
                 f = self.default


@@ -115,49 +124,64 @@ class Field(object):
         else:
             f = fdict[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 BookInfo(object):
+class WorkInfo(object):
+    __metaclass__ = DCInfo
+

     FIELDS = (
     FIELDS = (

-        Field( DCNS('creator'), 'author', as_person),
+        Field( DCNS('creator'), 'authors', as_person, salias='author', multiple=True),

         Field( DCNS('title'), 'title'),
         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.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('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('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('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('rights.license'), 'license', required=False),
         Field( DCNS('rights'), 'license_description'),

-        Field( DCNS('description'), 'description', required=False),

     )
 
     )
 

-    @property
-    def slug(self):
-        return self.url.rsplit('/', 1)[1]
-

     @classmethod
     @classmethod

-    def from_string(cls, xml):
+    def from_string(cls, xml, *args, **kwargs):

         from StringIO import StringIO
         from StringIO import StringIO

-        return cls.from_file(StringIO(xml))
+        return cls.from_file(StringIO(xml), *args, **kwargs)

 
     @classmethod
 
     @classmethod

-    def from_file(cls, xmlfile):
+    def from_file(cls, xmlfile, *args, **kwargs):

         desc_tag = None
         try:
             iter = etree.iterparse(xmlfile, ['start', 'end'])
         desc_tag = None
         try:
             iter = etree.iterparse(xmlfile, ['start', 'end'])


@@ -178,17 +202,17 @@ class BookInfo(object):
             # if there is no end, Expat should yell at us with an ExpatError
 
             # extract data from the element and make the info
             # 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
         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 = {}
         # 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.")
 
         if desc is None:
             raise NoDublinCore("No DublinCore section found.")


@@ -198,9 +222,9 @@ class BookInfo(object):
             fv.append(e.text)
             field_dict[e.tag] = fv
 
             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, 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. """
         """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. """


@@ -209,7 +233,7 @@ class BookInfo(object):
         self.fmap = {}
 
         for field in self.FIELDS:
         self.fmap = {}
 
         for field in self.FIELDS:

-            value = field.validate( dc_fields )
+            value = field.validate(dc_fields, strict=strict)

             setattr(self, 'prop_' + field.name, value)
             self.fmap[field.name] = field
             if field.salias: self.fmap[field.salias] = field
             setattr(self, 'prop_' + field.name, value)
             self.fmap[field.name] = field
             if field.salias: self.fmap[field.salias] = field


@@ -224,7 +248,7 @@ class BookInfo(object):
                 if not field.multiple:
                     raise "OUCH!! for field %s" % name
 
                 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)
 
         except (KeyError, AttributeError):
             return object.__getattribute__(self, name)
 


@@ -280,7 +304,6 @@ class BookInfo(object):
 
         return root
 
 
         return root
 

-

     def serialize(self):
         rdf = {}
         rdf['about'] = { 'uri': RDFNS('about'), 'value': self.about }
     def serialize(self):
         rdf = {}
         rdf['about'] = { 'uri': RDFNS('about'), 'value': self.about }


@@ -318,5 +341,31 @@ class BookInfo(object):
 
         return result
 
 
         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)