def tag_compiler(tags: Tags) -> Iterable[DXFTag]:
"""Special tag compiler for the DXF browser.
This compiler should never fail and always return printable tags:
- invalid point coordinates are returned as float("nan")
- invalid ints are returned as string
- invalid floats are returned as string
"""
def to_float(v: str) -> float:
try:
return float(v)
except ValueError:
return float("NaN")
count = len(tags)
index = 0
while index < count:
code, value = tags[index]
if code in POINT_CODES:
try:
y_code, y_value = tags[index + 1]
except IndexError: # x-coord as last tag
yield DXFTag(code, to_float(value))
return
if y_code != code + 10: # not an y-coord?
yield DXFTag(code, to_float(value)) # x-coord as single tag
index += 1
continue
try:
z_code, z_value = tags[index + 2]
except IndexError: # no z-coord exist
z_code = 0
z_value = 0
point: Sequence[float]
if z_code == code + 20: # is a z-coord?
point = (to_float(value), to_float(y_value), to_float(z_value))
index += 3
else: # a valid 2d point(x, y)
point = (to_float(value), to_float(y_value))
index += 2
yield DXFVertex(code, point)
else: # a single tag
try:
if code == 0:
value = value.strip()
yield DXFTag(code, TYPE_TABLE.get(code, str)(value))
except ValueError:
yield DXFTag(code, str(value)) # just as string
index += 1
def byte_tag_compiler(
tags: Iterable[DXFTag],
encoding=const.DEFAULT_ENCODING,
messages: List = None,
errors: str = 'surrogateescape',
) -> Iterable[DXFTag]:
""" Compiles DXF tag values imported by bytes_loader() into Python types.
Raises DXFStructureError() for invalid float values and invalid coordinate
values.
Expects DXF coordinates written in x, y[, z] order, see function
:func:`safe_tag_loader` for usage with applied repair filters.
Args:
tags: DXF tag generator, yielding tag values as bytes like bytes_loader()
encoding: text encoding
messages: list to store error messages
errors: specify decoding error handler
- "surrogateescape" to preserve possible binary data (default)
- "ignore" to use the replacement char U+FFFD "\ufffd" for invalid data
- "strict" to raise an :class:`UnicodeDecodeError` exception for invalid data
Raises:
DXFStructureError: Found invalid DXF tag or unexpected coordinate order.
"""
def error_msg(tag):
code = tag.code
value = tag.value.decode(encoding)
return f'Invalid tag ({code}, "{value}") near line: {line}.'
if messages is None:
messages = []
tags = iter(tags)
undo_tag = None
line = 0
while True:
try:
if undo_tag is not None:
x = undo_tag
undo_tag = None
else:
x = next(tags)
line += 2
code = x.code
if code in POINT_CODES:
y = next(tags) # y coordinate is mandatory
line += 2
# e.g. y-code for x-code=10 is 20
if y.code != code + 10:
raise const.DXFStructureError(
f"Missing required y-coordinate near line: {line}.")
# optional z coordinate
z = next(tags)
line += 2
try:
# is it a z-coordinate like (30, 0.0) for base x-code=10
if z.code == code + 20:
try:
point = (float(x.value), float(y.value),
float(z.value))
except ValueError: # search for any float values
point = (_search_float(x.value),
_search_float(y.value),
_search_float(z.value))
else:
try:
point = (float(x.value), float(y.value))
except ValueError: # seach for any float values
point = (
_search_float(x.value),
_search_float(y.value),
)
undo_tag = z
except ValueError:
raise const.DXFStructureError(
f'Invalid floating point values near line: {line}.')
yield DXFVertex(code, point)
elif code in BINARY_DATA:
# maybe pre compiled in low level tagger (binary DXF)
if isinstance(x, DXFBinaryTag):
tag = x
else:
try:
tag = DXFBinaryTag.from_string(code, x.value)
except ValueError:
raise const.DXFStructureError(
f'Invalid binary data near line: {line}.')
yield tag
else: # just a single tag
type_ = TYPE_TABLE.get(code, str)
value: bytes = x.value
if type_ is str:
if code == 0:
# remove white space from structure tags
value = x.value.strip().upper()
try: # 2 stages to document decoding errors
str_ = value.decode(encoding, errors='strict')
except UnicodeDecodeError:
str_ = value.decode(encoding, errors=errors)
messages.append(
(AuditError.DECODING_ERROR,
f'Fixed unicode decoding error near line {line}'))
# Convert DXF unicode notation "\U+xxxx" to unicode,
# but exclude structure tags (code>0):
if code and has_dxf_unicode(str_):
str_ = decode_dxf_unicode(str_)
yield DXFTag(code, str_)
else:
try:
# fast path for int and float
yield DXFTag(code, type_(value))
except ValueError:
# slow path - e.g. ProE stores int values as floats :((
if type_ is int:
try:
yield DXFTag(code, _search_int(x.value))
except ValueError:
raise const.DXFStructureError(error_msg(x))
elif type_ is float:
try:
yield DXFTag(code, _search_float(x.value))
except ValueError:
raise const.DXFStructureError(error_msg(x))
else:
raise const.DXFStructureError(error_msg(x))
except StopIteration:
return
def byte_tag_compiler(tags: Iterable[DXFTag],
encoding=const.DEFAULT_ENCODING) -> Iterable[DXFTag]:
""" Compiles DXF tag values imported by bytes_loader() into Python types.
Raises DXFStructureError() for invalid float values and invalid coordinate
values.
Expects DXF coordinates written in x, y[, z] order, see function
:func:`safe_tag_loader` for usage with applied repair filters.
Args:
tags: DXF tag generator, yielding tag values as bytes like bytes_loader()
encoding: text encoding
Raises:
DXFStructureError: Found invalid DXF tag or unexpected coordinate order.
"""
def error_msg(tag):
code = tag.code
value = tag.value.decode(encoding)
return f'Invalid tag ({code}, "{value}") near line: {line}.'
tags = iter(tags)
undo_tag = None
line = 0
while True:
try:
if undo_tag is not None:
x = undo_tag
undo_tag = None
else:
x = next(tags)
line += 2
code = x.code
if code in POINT_CODES:
y = next(tags) # y coordinate is mandatory
line += 2
# e.g. y-code for x-code=10 is 20
if y.code != code + 10:
raise const.DXFStructureError(
f"Missing required y-coordinate near line: {line}.")
# optional z coordinate
z = next(tags)
line += 2
try:
# is it a z-coordinate like (30, 0.0) for base x-code=10
if z.code == code + 20:
point = (float(x.value), float(y.value),
float(z.value))
else:
point = (float(x.value), float(y.value))
undo_tag = z
except ValueError:
raise const.DXFStructureError(
f'Invalid floating point values near line: {line}.')
yield DXFVertex(code, point)
elif code in BINARY_DATA:
# maybe pre compiled in low level tagger (binary DXF)
if isinstance(x, DXFBinaryTag):
tag = x
else:
try:
tag = DXFBinaryTag.from_string(code, x.value)
except ValueError:
raise const.DXFStructureError(
f'Invalid binary data near line: {line}.')
yield tag
else: # just a single tag
type_ = TYPE_TABLE.get(code, str)
value: bytes = x.value
if type_ is str:
if code == 0:
# remove white space from structure tags
value = x.value.strip()
yield DXFTag(code, value.decode(encoding))
else:
try:
# fast path for int and float
yield DXFTag(code, type_(value))
except ValueError:
# slow path - ProE stores int values as floats :((
if type_ is int:
try:
yield DXFTag(code, int(float(x.value)))
except ValueError:
raise const.DXFStructureError(error_msg(x))
else:
raise const.DXFStructureError(error_msg(x))
except StopIteration:
return