def from_segments(cls, segments: list
or collections.Iterable) -> "Interchange":
segments = iter(segments)
first_segment = next(segments)
if first_segment.tag == 'UNA':
unb = next(segments)
elif first_segment.tag == 'UNB':
unb = first_segment
else:
raise EDISyntaxError(
'An interchange must start with UNB or UNA and UNB')
# Loosy syntax check :
if len(unb.elements) < 4:
raise EDISyntaxError('Missing elements in UNB header')
datetime_str = '-'.join(unb.elements[3])
timestamp = datetime.datetime.strptime(datetime_str, '%y%m%d-%H%M')
interchange = Interchange(
syntax_identifier=unb.elements[0],
sender=unb.elements[1],
recipient=unb.elements[2],
timestamp=timestamp,
control_reference=unb.elements[4],
)
if first_segment.tag == 'UNA':
interchange.has_una_segment = True
interchange.characters = Characters.from_str(
first_segment.elements[0])
return interchange.add_segments(segment for segment in segments
if segment.tag != 'UNZ')
def from_segments(cls, segments: Union[list, Iterable]) -> "Interchange":
segments = iter(segments)
first_segment = next(segments)
if first_segment.tag == "UNA":
unb = next(segments)
elif first_segment.tag == "UNB":
unb = first_segment
else:
raise EDISyntaxError(
"An interchange must start with UNB or UNA and UNB")
# Loosy syntax check :
if len(unb.elements) < 4:
raise EDISyntaxError("Missing elements in UNB header")
datetime_str = "-".join(unb.elements[3])
timestamp = datetime.datetime.strptime(datetime_str, "%y%m%d-%H%M")
interchange = Interchange(
syntax_identifier=unb.elements[0],
sender=unb.elements[1],
recipient=unb.elements[2],
timestamp=timestamp,
control_reference=unb.elements[4],
)
if first_segment.tag == "UNA":
interchange.has_una_segment = True
interchange.characters = Characters.from_str(
first_segment.elements[0])
return interchange.add_segments(segments)
def get_messages(self) -> List[Message]:
message = None
for segment in self.segments:
if segment.tag == 'UNH':
if not message:
message = Message(segment.elements[0], segment.elements[1])
else:
raise EDISyntaxError(
f"Missing UNT segment before new UNH: {segment}")
elif segment.tag == 'UNT':
if message:
yield message
else:
raise EDISyntaxError(
f'UNT segment without matching UNH: "{segment}"')
else:
if message:
message.add_segment(segment)
def create_segment(name: str,
*elements: Union[str, List[str]],
validate: bool = True) -> Segment:
"""Create a new instance of the relevant class type.
:param name: The name of the segment
:param elements: The data elements for this segment
:param validate: bool if True, the created segment is validated before return
"""
if not SegmentFactory.characters:
SegmentFactory.characters = Characters()
# Basic segment type validation is done here.
# The more special validation must be done in the corresponding Segment
if not name:
raise EDISyntaxError("The tag of a segment must not be empty.")
if type(name) != str:
raise EDISyntaxError(
"The tag name of a segment must be a str, but is a {}: {}".
format(type(name), name))
if not name.isalnum():
raise EDISyntaxError(
"Tag '{}': A tag name must only contain alphanumeric characters."
.format(name))
for Plugin in SegmentProvider.plugins:
if Plugin().tag == name:
s = Plugin(name, *elements)
else:
# we don't support this kind of EDIFACT segment (yet), so
# just create a generic Segment()
s = Segment(name, *elements)
if validate:
if not s.validate():
raise EDISyntaxError(
"could not create '{}' Segment. Validation failed.".format(
name))
# FIXME: characters is not used!
return Segment(name, *elements)
def get_messages(self) -> List[Message]:
message = None
for segment in self.segments:
if segment.tag == "UNH":
if not message:
message = Message(segment.elements[0], segment.elements[1])
else:
raise EDISyntaxError(
"Missing UNT segment before new UNH: {}".format(
segment))
elif segment.tag == "UNT":
if message:
yield message
else:
raise EDISyntaxError(
'UNT segment without matching UNH: "{}"'.format(
segment))
else:
if message:
message.add_segment(segment)
def get_messages(self) -> List[Message]:
"""parses a list of messages out of the internal segments.
:raises EDISyntaxError if constraints are not met (e.g. UNH/UNT both correct)
TODO: parts of this here are better done in the validate() method
"""
message = None
last_segment = None
for segment in self.segments:
if segment.tag == "UNH":
if not message:
message = Message(segment.elements[0], segment.elements[1])
last_segment = segment
else:
raise EDISyntaxError(
"Missing UNT segment before new UNH: {}".format(
segment))
elif segment.tag == "UNT":
if message:
yield message
message = None
last_segment = segment
else:
raise EDISyntaxError(
'UNT segment without matching UNH: "{}"'.format(
segment))
else:
if message:
message.add_segment(segment)
last_segment = segment
if last_segment:
if not last_segment.tag == "UNT":
raise EDISyntaxError(
"UNH segment was not closed with a UNT segment.")