"""
Anything related to XMP metadata.
See https://en.wikipedia.org/wiki/Extensible_Metadata_Platform
"""
import datetime
import decimal
import re
from typing import (
Any,
Callable,
Dict,
Iterator,
List,
Optional,
TypeVar,
Union,
cast,
)
from xml.dom.minidom import Document
from xml.dom.minidom import Element as XmlElement
from xml.dom.minidom import parseString
from xml.parsers.expat import ExpatError
from ._utils import (
StreamType,
deprecate_with_replacement,
deprecation_with_replacement,
)
from .errors import PdfReadError
from .generic import ContentStream, PdfObject
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,
)
K = TypeVar("K")
def _identity(value: K) -> K:
return value
def _converter_date(value: str) -> datetime.datetime:
matches = iso8601.match(value)
if matches is None:
raise ValueError(f"Invalid date format: {value}")
year = int(matches.group("year"))
month = int(matches.group("month") or "1")
day = int(matches.group("day") or "1")
hour = int(matches.group("hour") or "0")
minute = int(matches.group("minute") or "0")
second = decimal.Decimal(matches.group("second") or "0")
seconds_dec = second.to_integral(decimal.ROUND_FLOOR)
milliseconds_dec = (second - seconds_dec) * 1000000
seconds = int(seconds_dec)
milliseconds = int(milliseconds_dec)
tzd = matches.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
def _getter_bag(
namespace: str, name: str
) -> Callable[["XmpInformation"], Optional[List[str]]]:
def get(self: "XmpInformation") -> Optional[List[str]]:
cached = self.cache.get(namespace, {}).get(name)
if cached:
return cached
retval = []
for element in self.get_element("", 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._get_text(item)
retval.append(value)
ns_cache = self.cache.setdefault(namespace, {})
ns_cache[name] = retval
return retval
return get
def _getter_seq(
namespace: str, name: str, converter: Callable[[Any], Any] = _identity
) -> Callable[["XmpInformation"], Optional[List[Any]]]:
def get(self: "XmpInformation") -> Optional[List[Any]]:
cached = self.cache.get(namespace, {}).get(name)
if cached:
return cached
retval = []
for element in self.get_element("", 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._get_text(item)
value = converter(value)
retval.append(value)
else:
value = converter(self._get_text(element))
retval.append(value)
ns_cache = self.cache.setdefault(namespace, {})
ns_cache[name] = retval
return retval
return get
def _getter_langalt(
namespace: str, name: str
) -> Callable[["XmpInformation"], Optional[Dict[Any, Any]]]:
def get(self: "XmpInformation") -> Optional[Dict[Any, Any]]:
cached = self.cache.get(namespace, {}).get(name)
if cached:
return cached
retval = {}
for element in self.get_element("", 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._get_text(item)
retval[item.getAttribute("xml:lang")] = value
else:
retval["x-default"] = self._get_text(element)
ns_cache = self.cache.setdefault(namespace, {})
ns_cache[name] = retval
return retval
return get
def _getter_single(
namespace: str, name: str, converter: Callable[[str], Any] = _identity
) -> Callable[["XmpInformation"], Optional[Any]]:
def get(self: "XmpInformation") -> Optional[Any]:
cached = self.cache.get(namespace, {}).get(name)
if cached:
return cached
value = None
for element in self.get_element("", namespace, name):
if element.nodeType == element.ATTRIBUTE_NODE:
value = element.nodeValue
else:
value = self._get_text(element)
break
if value is not None:
value = converter(value)
ns_cache = self.cache.setdefault(namespace, {})
ns_cache[name] = value
return value
return get
class XmpInformation(PdfObject):
"""
An object that represents Adobe XMP metadata.
Usually accessed by :py:attr:`xmp_metadata()<PyPDF2.PdfReader.xmp_metadata>`
:raises PdfReadError: if XML is invalid
"""
def __init__(self, stream: ContentStream) -> None:
self.stream = stream
try:
data = self.stream.get_data()
doc_root: Document = parseString(data)
except ExpatError as e:
raise PdfReadError(f"XML in XmpInformation was invalid: {e}")
self.rdf_root: XmlElement = doc_root.getElementsByTagNameNS(
RDF_NAMESPACE, "RDF"
)[0]
self.cache: Dict[Any, Any] = {}
@property
def rdfRoot(self) -> XmlElement: # pragma: no cover
deprecate_with_replacement("rdfRoot", "rdf_root", "4.0.0")
return self.rdf_root
def write_to_stream(
self, stream: StreamType, encryption_key: Union[None, str, bytes]
) -> None:
self.stream.write_to_stream(stream, encryption_key)
def writeToStream(
self, stream: StreamType, encryption_key: Union[None, str, bytes]
) -> None: # pragma: no cover
"""
.. deprecated:: 1.28.0
Use :meth:`write_to_stream` instead.
"""
deprecation_with_replacement("writeToStream", "write_to_stream", "3.0.0")
self.write_to_stream(stream, encryption_key)
def get_element(self, about_uri: str, namespace: str, name: str) -> Iterator[Any]:
for desc in self.rdf_root.getElementsByTagNameNS(RDF_NAMESPACE, "Description"):
if desc.getAttributeNS(RDF_NAMESPACE, "about") == about_uri:
attr = desc.getAttributeNodeNS(namespace, name)
if attr is not None:
yield attr
yield from desc.getElementsByTagNameNS(namespace, name)
def getElement(
self, aboutUri: str, namespace: str, name: str
) -> Iterator[Any]: # pragma: no cover
"""
.. deprecated:: 1.28.0
Use :meth:`get_element` instead.
"""
deprecation_with_replacement("getElement", "get_element", "3.0.0")
return self.get_element(aboutUri, namespace, name)
def get_nodes_in_namespace(self, about_uri: str, namespace: str) -> Iterator[Any]:
for desc in self.rdf_root.getElementsByTagNameNS(RDF_NAMESPACE, "Description"):
if desc.getAttributeNS(RDF_NAMESPACE, "about") == about_uri:
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 getNodesInNamespace(
self, aboutUri: str, namespace: str
) -> Iterator[Any]: # pragma: no cover
"""
.. deprecated:: 1.28.0
Use :meth:`get_nodes_in_namespace` instead.
"""
deprecation_with_replacement(
"getNodesInNamespace", "get_nodes_in_namespace", "3.0.0"
)
return self.get_nodes_in_namespace(aboutUri, namespace)
def _get_text(self, element: XmlElement) -> str:
text = ""
for child in element.childNodes:
if child.nodeType == child.TEXT_NODE:
text += child.data
return text
dc_contributor = property(_getter_bag(DC_NAMESPACE, "contributor"))
"""
Contributors to the resource (other than the authors). An unsorted
array of names.
"""
dc_coverage = property(_getter_single(DC_NAMESPACE, "coverage"))
"""
Text describing the extent or scope of the resource.
"""
dc_creator = property(_getter_seq(DC_NAMESPACE, "creator"))
"""
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 significance to
the resource. The dates and times are in UTC.
"""
dc_description = property(_getter_langalt(DC_NAMESPACE, "description"))
"""
A language-keyed dictionary of textual descriptions of the content of the
resource.
"""
dc_format = property(_getter_single(DC_NAMESPACE, "format"))
"""
The mime-type of the resource.
"""
dc_identifier = property(_getter_single(DC_NAMESPACE, "identifier"))
"""
Unique identifier of the resource.
"""
dc_language = property(_getter_bag(DC_NAMESPACE, "language"))
"""
An unordered array specifying the languages used in the resource.
"""
dc_publisher = property(_getter_bag(DC_NAMESPACE, "publisher"))
"""
An unordered array of publisher names.
"""
dc_relation = property(_getter_bag(DC_NAMESPACE, "relation"))
"""
An unordered array of text descriptions of relationships to other
documents.
"""
dc_rights = property(_getter_langalt(DC_NAMESPACE, "rights"))
"""
A language-keyed dictionary of textual descriptions of the rights the
user has to this resource.
"""
dc_source = property(_getter_single(DC_NAMESPACE, "source"))
"""
Unique identifier of the work from which this resource was derived.
"""
dc_subject = property(_getter_bag(DC_NAMESPACE, "subject"))
"""
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"))
"""
A language-keyed dictionary of the title of the resource.
"""
dc_type = property(_getter_bag(DC_NAMESPACE, "type"))
"""
An unordered array of textual descriptions of the document type.
"""
pdf_keywords = property(_getter_single(PDF_NAMESPACE, "Keywords"))
"""
An unformatted text string representing document keywords.
"""
pdf_pdfversion = property(_getter_single(PDF_NAMESPACE, "PDFVersion"))
"""
The PDF file version, for example 1.0, 1.3.
"""
pdf_producer = property(_getter_single(PDF_NAMESPACE, "Producer"))
"""
The name of the tool that created the PDF document.
"""
xmp_create_date = 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.
"""
@property
def xmp_createDate(self) -> datetime.datetime: # pragma: no cover
deprecate_with_replacement("xmp_createDate", "xmp_create_date", "4.0.0")
return self.xmp_create_date
@xmp_createDate.setter
def xmp_createDate(self, value: datetime.datetime) -> None: # pragma: no cover
deprecate_with_replacement("xmp_createDate", "xmp_create_date", "4.0.0")
self.xmp_create_date = value
xmp_modify_date = 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.
"""
@property
def xmp_modifyDate(self) -> datetime.datetime: # pragma: no cover
deprecate_with_replacement("xmp_modifyDate", "xmp_modify_date", "4.0.0")
return self.xmp_modify_date
@xmp_modifyDate.setter
def xmp_modifyDate(self, value: datetime.datetime) -> None: # pragma: no cover
deprecate_with_replacement("xmp_modifyDate", "xmp_modify_date", "4.0.0")
self.xmp_modify_date = value
xmp_metadata_date = 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.
"""
@property
def xmp_metadataDate(self) -> datetime.datetime: # pragma: no cover
deprecate_with_replacement("xmp_metadataDate", "xmp_metadata_date", "4.0.0")
return self.xmp_metadata_date
@xmp_metadataDate.setter
def xmp_metadataDate(self, value: datetime.datetime) -> None: # pragma: no cover
deprecate_with_replacement("xmp_metadataDate", "xmp_metadata_date", "4.0.0")
self.xmp_metadata_date = value
xmp_creator_tool = property(_getter_single(XMP_NAMESPACE, "CreatorTool"))
"""The name of the first known tool used to create the resource."""
@property
def xmp_creatorTool(self) -> str: # pragma: no cover
deprecation_with_replacement("xmp_creatorTool", "xmp_creator_tool", "3.0.0")
return self.xmp_creator_tool
@xmp_creatorTool.setter
def xmp_creatorTool(self, value: str) -> None: # pragma: no cover
deprecation_with_replacement("xmp_creatorTool", "xmp_creator_tool", "3.0.0")
self.xmp_creator_tool = value
xmpmm_document_id = property(_getter_single(XMPMM_NAMESPACE, "DocumentID"))
"""
The common identifier for all versions and renditions of this resource.
"""
@property
def xmpmm_documentId(self) -> str: # pragma: no cover
deprecation_with_replacement("xmpmm_documentId", "xmpmm_document_id", "3.0.0")
return self.xmpmm_document_id
@xmpmm_documentId.setter
def xmpmm_documentId(self, value: str) -> None: # pragma: no cover
deprecation_with_replacement("xmpmm_documentId", "xmpmm_document_id", "3.0.0")
self.xmpmm_document_id = value
xmpmm_instance_id = property(_getter_single(XMPMM_NAMESPACE, "InstanceID"))
"""
An identifier for a specific incarnation of a document, updated each
time a file is saved.
"""
@property
def xmpmm_instanceId(self) -> str: # pragma: no cover
deprecation_with_replacement("xmpmm_instanceId", "xmpmm_instance_id", "3.0.0")
return cast(str, self.xmpmm_instance_id)
@xmpmm_instanceId.setter
def xmpmm_instanceId(self, value: str) -> None: # pragma: no cover
deprecation_with_replacement("xmpmm_instanceId", "xmpmm_instance_id", "3.0.0")
self.xmpmm_instance_id = value
@property
def custom_properties(self) -> Dict[Any, Any]:
"""
Retrieve custom metadata properties defined in the undocumented pdfx
metadata schema.
:return: a dictionary of key/value items for custom metadata properties.
"""
if not hasattr(self, "_custom_properties"):
self._custom_properties = {}
for node in self.get_nodes_in_namespace("", PDFX_NAMESPACE):
key = node.localName
while True:
# see documentation about PDFX_NAMESPACE earlier in file
idx = key.find("\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._get_text(node)
self._custom_properties[key] = value
return self._custom_properties