"""
API to PAGE-XML, generated with generateDS from XML schema.
"""
from io import StringIO
from typing import Dict, Union, Any
from lxml import etree as ET
from elementpath import XPath2Parser, XPathContext
__all__ = [
'parse',
'parseEtree',
'parseString',
'OcrdPage',
'OcrdPageType',
"AdvertRegionType",
"AlternativeImageType",
"BaselineType",
"BorderType",
"ChartRegionType",
"ChemRegionType",
"CoordsType",
"CustomRegionType",
"GlyphType",
"GraphemeBaseType",
"GraphemeGroupType",
"GraphemeType",
"GraphemesType",
"GraphicRegionType",
"GridPointsType",
"GridType",
"ImageRegionType",
"LabelType",
"LabelsType",
"LayerType",
"LayersType",
"LineDrawingRegionType",
"MapRegionType",
"MathsRegionType",
"MetadataItemType",
"MetadataType",
"MusicRegionType",
"NoiseRegionType",
"NonPrintingCharType",
"OrderedGroupIndexedType",
"OrderedGroupType",
"PageType",
"PcGtsType",
"PrintSpaceType",
"ReadingOrderType",
"RegionRefIndexedType",
"RegionRefType",
"RegionType",
"RelationType",
"RelationsType",
"RolesType",
"SeparatorRegionType",
"TableCellRoleType",
"TableRegionType",
"TextEquivType",
"TextLineType",
"TextRegionType",
"TextStyleType",
"UnknownRegionType",
"UnorderedGroupIndexedType",
"UnorderedGroupType",
"UserAttributeType",
"UserDefinedType",
"WordType",
'to_xml'
]
from .ocrd_page_generateds import (
parse,
parseEtree,
parseString,
AdvertRegionType,
AlternativeImageType,
BaselineType,
BorderType,
ChartRegionType,
ChemRegionType,
CoordsType,
CustomRegionType,
GlyphType,
GraphemeBaseType,
GraphemeGroupType,
GraphemeType,
GraphemesType,
GraphicRegionType,
GridPointsType,
GridType,
ImageRegionType,
LabelType,
LabelsType,
LayerType,
LayersType,
LineDrawingRegionType,
MapRegionType,
MathsRegionType,
MetadataItemType,
MetadataType,
MusicRegionType,
NoiseRegionType,
NonPrintingCharType,
OrderedGroupIndexedType,
OrderedGroupType,
PageType,
PcGtsType,
PrintSpaceType,
ReadingOrderType,
RegionRefIndexedType,
RegionRefType,
RegionType,
RelationType,
RelationsType,
RolesType,
SeparatorRegionType,
TableCellRoleType,
TableRegionType,
TextEquivType,
TextLineType,
TextRegionType,
TextStyleType,
UnknownRegionType,
UnorderedGroupIndexedType,
UnorderedGroupType,
UserAttributeType,
UserDefinedType,
WordType
)
from .constants import NAMESPACES
from .xpath_functions import pc_functions
# add docstrings
parse.__doc__ = (
"""Parse a file, create the object tree, and export it.
Arguments:
inFileName (str) -- Path to the PAGE-XML file.
print_warnings (boolean) -- If true, write parser \
warnings to stderr.
Returns:
The root object in the tree.
"""
)
parseEtree.__doc__ = (
"""Parse a file, create the object tree, and export it. Return tree and mappings, too.
Arguments:
inFileName (str) -- Path to the PAGE-XML file.
print_warnings (boolean) -- If true, write parser \
warnings to stderr.
Returns:
A tuple of
* The root object in the tree.
* The full node tree.
* A mapping from object IDs to tree nodes.
* A reverse mapping from tree nodes to object IDs.
"""
)
# fix generated (malformed) docstrings
parseString.__doc__ = (
"""Parse a string, create the object tree, and export it.
Arguments:
inString (str) -- This XML fragment should not start \
with an XML declaration containing an encoding.
Returns:
The root object in the tree.
"""
)
[docs]
class OcrdPage():
"""
Proxy object for :py:class:`ocrd_models.PcGtsType` (i.e. PRImA PAGE-XML
for page content, rendered as object model by generateDS) that also offers access
to the underlying etree, element-node mapping and reverse mapping, too (cf.
:py:func:`ocrd_models.ocrd_page.parseEtree`)
"""
def __init__(
self,
pcgts : PcGtsType,
etree : ET._Element,
mapping : Dict[str, ET._Element],
revmap : Dict[ET._Element, Any],
):
self._pcgts = pcgts
self.etree = etree
self.mapping = mapping
self.revmap = revmap
self.xpath_parser = XPath2Parser(namespaces={
'page': NAMESPACES['page'],
'pc': NAMESPACES['page']})
for func in pc_functions:
name = func.__name__.replace('_', '-')
if name.startswith('pc-'):
name = name[3:]
elif name.startswith('pc'):
name = name[2:]
# register
self.xpath_parser.external_function(func, name=name, prefix='pc')
self.xpath_context = XPathContext(self.etree)
self.xpath = lambda expression: self.xpath_parser.parse(expression).get_results(self.xpath_context)
def __getattr__(self, name):
return getattr(self._pcgts, name)
OcrdPageType = Union[OcrdPage, PcGtsType]
[docs]
def to_xml(el, skip_declaration=False) -> str:
"""
Serialize ``pc:PcGts`` document as string.
"""
# XXX remove potential empty ReadingOrder
if hasattr(el, 'prune_ReadingOrder'):
el.prune_ReadingOrder()
if hasattr(el, 'original_tagname_'):
name = el.original_tagname_ or 'PcGts'
else:
name = 'PcGts'
sio = StringIO()
el.export(
outfile=sio,
level=0,
name_=name,
namespaceprefix_='pc:',
namespacedef_='xmlns:pc="%s" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="%s %s/pagecontent.xsd"' % (
NAMESPACES['page'],
NAMESPACES['page'],
NAMESPACES['page']
))
ret = sio.getvalue()
if not skip_declaration:
ret = '<?xml version="1.0" encoding="UTF-8"?>\n' + ret
return ret
