+
+from dcparser import (as_person, as_date, Field, WorkInfo, DCNS)
+from librarian import (RDFNS, ValidationError, NoDublinCore, ParseError, WLURI)
+from xml.parsers.expat import ExpatError
+from os import path
+from StringIO import StringIO
+from lxml import etree
+from lxml.etree import (XMLSyntaxError, XSLTApplyError)
+import re
+
+
+class WLPictureURI(WLURI):
+ _re_wl_uri = re.compile('http://wolnelektury.pl/katalog/obraz/'
+ '(?P<slug>[-a-z0-9]+)(/(?P<lang>[a-z]{3}))?/?$')
+
+ def __init__(self, *args, **kw):
+ super(WLPictureURI, self).__init__(*args, **kw)
+
+ @classmethod
+ def from_slug_and_lang(cls, slug, lang):
+ uri = 'http://wolnelektury.pl/katalog/obraz/%s/' % slug
+ return cls(uri)
+
+ def filename_stem(self):
+ return self.slug
+
+
+class PictureInfo(WorkInfo):
+ """
+ Dublin core metadata for a picture
+ """
+ FIELDS = (
+ Field(DCNS('format.dimensions.digital'), 'dimensions', required=False),
+ Field(DCNS('format.dimensions.original'), 'dimensions_original', required=False),
+ Field(DCNS('format.physical'), 'physical', required=False),
+ Field(DCNS('format'), 'mime_type', required=False),
+ Field(DCNS('identifier.url'), 'url', WLPictureURI),
+ )
+
+ def validate(self):
+ """
+ WorkInfo has a language validation code only, which we do not need.
+ """
+ pass
+
+
+class ImageStore(object):
+ EXT = ['gif', 'jpeg', 'png', 'swf', 'psd', 'bmp'
+ 'tiff', 'tiff', 'jpc', 'jp2', 'jpf', 'jb2', 'swc',
+ 'aiff', 'wbmp', 'xbm']
+ MIME = ['image/gif', 'image/jpeg', 'image/png',
+ 'application/x-shockwave-flash', 'image/psd', 'image/bmp',
+ 'image/tiff', 'image/tiff', 'application/octet-stream',
+ 'image/jp2', 'application/octet-stream', 'application/octet-stream',
+ 'application/x-shockwave-flash', 'image/iff', 'image/vnd.wap.wbmp', 'image/xbm']
+
+ def __init__(self, dir_):
+ self.dir = dir_
+ return super(ImageStore, self).__init__()
+
+ def path(self, slug, mime_type):
+ """
+ Finds file by slug and mime type in our iamge store.
+ Returns a file objects (perhaps should return a filename?)
+ """
+ try:
+ i = self.MIME.index(mime_type)
+ except ValueError:
+ err = ValueError("Picture %s has unknown mime type: %s" % (slug, mime_type))
+ err.slug = slug
+ err.mime_type = mime_type
+ raise err
+ ext = self.EXT[i]
+ # add some common extensions tiff->tif, jpeg->jpg
+ return path.join(self.dir, slug + '.' + ext)
+
+
+class WLPicture(object):
+ def __init__(self, edoc, parse_dublincore=True, image_store=None):
+ self.edoc = edoc
+ self.image_store = image_store
+
+ root_elem = edoc.getroot()
+
+ dc_path = './/' + RDFNS('RDF')
+
+ if root_elem.tag != 'picture':
+ raise ValidationError("Invalid root element. Found '%s', should be 'picture'" % root_elem.tag)
+
+ if parse_dublincore:
+ self.rdf_elem = root_elem.find(dc_path)
+
+ if self.rdf_elem is None:
+ raise NoDublinCore('Document has no DublinCore - which is required.')
+
+ self.picture_info = PictureInfo.from_element(self.rdf_elem)
+ else:
+ self.picture_info = None
+
+ @classmethod
+ def from_string(cls, xml, *args, **kwargs):
+ return cls.from_file(StringIO(xml), *args, **kwargs)
+
+ @classmethod
+ def from_file(cls, xmlfile, parse_dublincore=True, image_store=None):
+
+ # first, prepare for parsing
+ if isinstance(xmlfile, basestring):
+ file = open(xmlfile, 'rb')
+ try:
+ data = file.read()
+ finally:
+ file.close()
+ else:
+ data = xmlfile.read()
+
+ if not isinstance(data, unicode):
+ data = data.decode('utf-8')
+
+ data = data.replace(u'\ufeff', '')
+
+ # assume images are in the same directory
+ if image_store is None and xmlfile.name is not None:
+ image_store = ImageStore(path.dirname(xmlfile.name))
+
+ try:
+ parser = etree.XMLParser(remove_blank_text=False)
+ tree = etree.parse(StringIO(data.encode('utf-8')), parser)
+
+ return cls(tree, parse_dublincore=parse_dublincore, image_store=image_store)
+ except (ExpatError, XMLSyntaxError, XSLTApplyError), e:
+ raise ParseError(e)
+
+ @property
+ def mime_type(self):
+ if self.picture_info is None:
+ raise ValueError('DC is not loaded, hence we don\'t know the image type')
+ return self.picture_info.mime_type
+
+ @property
+ def slug(self):
+ return self.picture_info.url.slug
+
+ @property
+ def image_path(self):
+ if self.image_store is None:
+ raise ValueError("No image store associated with whis WLPicture.")
+ return self.image_store.path(self.slug, self.mime_type)
+
+ def image_file(self, *args, **kwargs):
+ return open(self.image_path, *args, **kwargs)
fnp / librarian.git / commitdiff
