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Diffstat (limited to 'PdfFileTransformer/PyPDF2/xmp.py')
| -rw-r--r-- | PdfFileTransformer/PyPDF2/xmp.py | 358 |
1 files changed, 358 insertions, 0 deletions
diff --git a/PdfFileTransformer/PyPDF2/xmp.py b/PdfFileTransformer/PyPDF2/xmp.py new file mode 100644 index 0000000..7ba62f0 --- /dev/null +++ b/PdfFileTransformer/PyPDF2/xmp.py @@ -0,0 +1,358 @@ +import re +import datetime +import decimal +from .generic import PdfObject +from xml.dom import getDOMImplementation +from xml.dom.minidom import parseString +from .utils import u_ + +RDF_NAMESPACE = "http://www.w3.org/1999/02/22-rdf-syntax-ns#" +DC_NAMESPACE = "http://purl.org/dc/elements/1.1/" +XMP_NAMESPACE = "http://ns.adobe.com/xap/1.0/" +PDF_NAMESPACE = "http://ns.adobe.com/pdf/1.3/" +XMPMM_NAMESPACE = "http://ns.adobe.com/xap/1.0/mm/" + +# What is the PDFX namespace, you might ask? I might ask that too. It's +# a completely undocumented namespace used to place "custom metadata" +# properties, which are arbitrary metadata properties with no semantic or +# documented meaning. Elements in the namespace are key/value-style storage, +# where the element name is the key and the content is the value. The keys +# are transformed into valid XML identifiers by substituting an invalid +# identifier character with \u2182 followed by the unicode hex ID of the +# original character. A key like "my car" is therefore "my\u21820020car". +# +# \u2182, in case you're wondering, is the unicode character +# \u{ROMAN NUMERAL TEN THOUSAND}, a straightforward and obvious choice for +# escaping characters. +# +# Intentional users of the pdfx namespace should be shot on sight. A +# custom data schema and sensical XML elements could be used instead, as is +# suggested by Adobe's own documentation on XMP (under "Extensibility of +# Schemas"). +# +# Information presented here on the /pdfx/ schema is a result of limited +# reverse engineering, and does not constitute a full specification. +PDFX_NAMESPACE = "http://ns.adobe.com/pdfx/1.3/" + +iso8601 = re.compile(""" + (?P<year>[0-9]{4}) + (- + (?P<month>[0-9]{2}) + (- + (?P<day>[0-9]+) + (T + (?P<hour>[0-9]{2}): + (?P<minute>[0-9]{2}) + (:(?P<second>[0-9]{2}(.[0-9]+)?))? + (?P<tzd>Z|[-+][0-9]{2}:[0-9]{2}) + )? + )? + )? + """, re.VERBOSE) + + +class XmpInformation(PdfObject): + """ + An object that represents Adobe XMP metadata. + Usually accessed by :meth:`getXmpMetadata()<PyPDF2.PdfFileReader.getXmpMetadata>` + """ + + def __init__(self, stream): + self.stream = stream + docRoot = parseString(self.stream.getData()) + self.rdfRoot = docRoot.getElementsByTagNameNS(RDF_NAMESPACE, "RDF")[0] + self.cache = {} + + def writeToStream(self, stream, encryption_key): + self.stream.writeToStream(stream, encryption_key) + + def getElement(self, aboutUri, namespace, name): + for desc in self.rdfRoot.getElementsByTagNameNS(RDF_NAMESPACE, "Description"): + if desc.getAttributeNS(RDF_NAMESPACE, "about") == aboutUri: + attr = desc.getAttributeNodeNS(namespace, name) + if attr != None: + yield attr + for element in desc.getElementsByTagNameNS(namespace, name): + yield element + + def getNodesInNamespace(self, aboutUri, namespace): + for desc in self.rdfRoot.getElementsByTagNameNS(RDF_NAMESPACE, "Description"): + if desc.getAttributeNS(RDF_NAMESPACE, "about") == aboutUri: + for i in range(desc.attributes.length): + attr = desc.attributes.item(i) + if attr.namespaceURI == namespace: + yield attr + for child in desc.childNodes: + if child.namespaceURI == namespace: + yield child + + def _getText(self, element): + text = "" + for child in element.childNodes: + if child.nodeType == child.TEXT_NODE: + text += child.data + return text + + def _converter_string(value): + return value + + def _converter_date(value): + m = iso8601.match(value) + year = int(m.group("year")) + month = int(m.group("month") or "1") + day = int(m.group("day") or "1") + hour = int(m.group("hour") or "0") + minute = int(m.group("minute") or "0") + second = decimal.Decimal(m.group("second") or "0") + seconds = second.to_integral(decimal.ROUND_FLOOR) + milliseconds = (second - seconds) * 1000000 + tzd = m.group("tzd") or "Z" + dt = datetime.datetime(year, month, day, hour, minute, seconds, milliseconds) + if tzd != "Z": + tzd_hours, tzd_minutes = [int(x) for x in tzd.split(":")] + tzd_hours *= -1 + if tzd_hours < 0: + tzd_minutes *= -1 + dt = dt + datetime.timedelta(hours=tzd_hours, minutes=tzd_minutes) + return dt + _test_converter_date = staticmethod(_converter_date) + + def _getter_bag(namespace, name, converter): + def get(self): + cached = self.cache.get(namespace, {}).get(name) + if cached: + return cached + retval = [] + for element in self.getElement("", namespace, name): + bags = element.getElementsByTagNameNS(RDF_NAMESPACE, "Bag") + if len(bags): + for bag in bags: + for item in bag.getElementsByTagNameNS(RDF_NAMESPACE, "li"): + value = self._getText(item) + value = converter(value) + retval.append(value) + ns_cache = self.cache.setdefault(namespace, {}) + ns_cache[name] = retval + return retval + return get + + def _getter_seq(namespace, name, converter): + def get(self): + cached = self.cache.get(namespace, {}).get(name) + if cached: + return cached + retval = [] + for element in self.getElement("", namespace, name): + seqs = element.getElementsByTagNameNS(RDF_NAMESPACE, "Seq") + if len(seqs): + for seq in seqs: + for item in seq.getElementsByTagNameNS(RDF_NAMESPACE, "li"): + value = self._getText(item) + value = converter(value) + retval.append(value) + else: + value = converter(self._getText(element)) + retval.append(value) + ns_cache = self.cache.setdefault(namespace, {}) + ns_cache[name] = retval + return retval + return get + + def _getter_langalt(namespace, name, converter): + def get(self): + cached = self.cache.get(namespace, {}).get(name) + if cached: + return cached + retval = {} + for element in self.getElement("", namespace, name): + alts = element.getElementsByTagNameNS(RDF_NAMESPACE, "Alt") + if len(alts): + for alt in alts: + for item in alt.getElementsByTagNameNS(RDF_NAMESPACE, "li"): + value = self._getText(item) + value = converter(value) + retval[item.getAttribute("xml:lang")] = value + else: + retval["x-default"] = converter(self._getText(element)) + ns_cache = self.cache.setdefault(namespace, {}) + ns_cache[name] = retval + return retval + return get + + def _getter_single(namespace, name, converter): + def get(self): + cached = self.cache.get(namespace, {}).get(name) + if cached: + return cached + value = None + for element in self.getElement("", namespace, name): + if element.nodeType == element.ATTRIBUTE_NODE: + value = element.nodeValue + else: + value = self._getText(element) + break + if value != None: + value = converter(value) + ns_cache = self.cache.setdefault(namespace, {}) + ns_cache[name] = value + return value + return get + + dc_contributor = property(_getter_bag(DC_NAMESPACE, "contributor", _converter_string)) + """ + Contributors to the resource (other than the authors). An unsorted + array of names. + """ + + dc_coverage = property(_getter_single(DC_NAMESPACE, "coverage", _converter_string)) + """ + Text describing the extent or scope of the resource. + """ + + dc_creator = property(_getter_seq(DC_NAMESPACE, "creator", _converter_string)) + """ + A sorted array of names of the authors of the resource, listed in order + of precedence. + """ + + dc_date = property(_getter_seq(DC_NAMESPACE, "date", _converter_date)) + """ + A sorted array of dates (datetime.datetime instances) of signifigance to + the resource. The dates and times are in UTC. + """ + + dc_description = property(_getter_langalt(DC_NAMESPACE, "description", _converter_string)) + """ + A language-keyed dictionary of textual descriptions of the content of the + resource. + """ + + dc_format = property(_getter_single(DC_NAMESPACE, "format", _converter_string)) + """ + The mime-type of the resource. + """ + + dc_identifier = property(_getter_single(DC_NAMESPACE, "identifier", _converter_string)) + """ + Unique identifier of the resource. + """ + + dc_language = property(_getter_bag(DC_NAMESPACE, "language", _converter_string)) + """ + An unordered array specifying the languages used in the resource. + """ + + dc_publisher = property(_getter_bag(DC_NAMESPACE, "publisher", _converter_string)) + """ + An unordered array of publisher names. + """ + + dc_relation = property(_getter_bag(DC_NAMESPACE, "relation", _converter_string)) + """ + An unordered array of text descriptions of relationships to other + documents. + """ + + dc_rights = property(_getter_langalt(DC_NAMESPACE, "rights", _converter_string)) + """ + A language-keyed dictionary of textual descriptions of the rights the + user has to this resource. + """ + + dc_source = property(_getter_single(DC_NAMESPACE, "source", _converter_string)) + """ + Unique identifier of the work from which this resource was derived. + """ + + dc_subject = property(_getter_bag(DC_NAMESPACE, "subject", _converter_string)) + """ + An unordered array of descriptive phrases or keywrods that specify the + topic of the content of the resource. + """ + + dc_title = property(_getter_langalt(DC_NAMESPACE, "title", _converter_string)) + """ + A language-keyed dictionary of the title of the resource. + """ + + dc_type = property(_getter_bag(DC_NAMESPACE, "type", _converter_string)) + """ + An unordered array of textual descriptions of the document type. + """ + + pdf_keywords = property(_getter_single(PDF_NAMESPACE, "Keywords", _converter_string)) + """ + An unformatted text string representing document keywords. + """ + + pdf_pdfversion = property(_getter_single(PDF_NAMESPACE, "PDFVersion", _converter_string)) + """ + The PDF file version, for example 1.0, 1.3. + """ + + pdf_producer = property(_getter_single(PDF_NAMESPACE, "Producer", _converter_string)) + """ + The name of the tool that created the PDF document. + """ + + xmp_createDate = property(_getter_single(XMP_NAMESPACE, "CreateDate", _converter_date)) + """ + The date and time the resource was originally created. The date and + time are returned as a UTC datetime.datetime object. + """ + + xmp_modifyDate = property(_getter_single(XMP_NAMESPACE, "ModifyDate", _converter_date)) + """ + The date and time the resource was last modified. The date and time + are returned as a UTC datetime.datetime object. + """ + + xmp_metadataDate = property(_getter_single(XMP_NAMESPACE, "MetadataDate", _converter_date)) + """ + The date and time that any metadata for this resource was last + changed. The date and time are returned as a UTC datetime.datetime + object. + """ + + xmp_creatorTool = property(_getter_single(XMP_NAMESPACE, "CreatorTool", _converter_string)) + """ + The name of the first known tool used to create the resource. + """ + + xmpmm_documentId = property(_getter_single(XMPMM_NAMESPACE, "DocumentID", _converter_string)) + """ + The common identifier for all versions and renditions of this resource. + """ + + xmpmm_instanceId = property(_getter_single(XMPMM_NAMESPACE, "InstanceID", _converter_string)) + """ + An identifier for a specific incarnation of a document, updated each + time a file is saved. + """ + + def custom_properties(self): + if not hasattr(self, "_custom_properties"): + self._custom_properties = {} + for node in self.getNodesInNamespace("", PDFX_NAMESPACE): + key = node.localName + while True: + # see documentation about PDFX_NAMESPACE earlier in file + idx = key.find(u_("\u2182")) + if idx == -1: + break + key = key[:idx] + chr(int(key[idx+1:idx+5], base=16)) + key[idx+5:] + if node.nodeType == node.ATTRIBUTE_NODE: + value = node.nodeValue + else: + value = self._getText(node) + self._custom_properties[key] = value + return self._custom_properties + + custom_properties = property(custom_properties) + """ + Retrieves custom metadata properties defined in the undocumented pdfx + metadata schema. + + :return: a dictionary of key/value items for custom metadata properties. + :rtype: dict + """ |