112 lines
4.1 KiB
Python
112 lines
4.1 KiB
Python
|
|
__all__ = ['Serializer', 'SerializerError']
|
|
|
|
from .error import YAMLError
|
|
from .events import *
|
|
from .nodes import *
|
|
|
|
class SerializerError(YAMLError):
|
|
pass
|
|
|
|
class Serializer:
|
|
|
|
ANCHOR_TEMPLATE = 'id%03d'
|
|
|
|
def __init__(self, encoding=None,
|
|
explicit_start=None, explicit_end=None, version=None, tags=None):
|
|
self.use_encoding = encoding
|
|
self.use_explicit_start = explicit_start
|
|
self.use_explicit_end = explicit_end
|
|
self.use_version = version
|
|
self.use_tags = tags
|
|
self.serialized_nodes = {}
|
|
self.anchors = {}
|
|
self.last_anchor_id = 0
|
|
self.closed = None
|
|
|
|
def open(self):
|
|
if self.closed is None:
|
|
self.emit(StreamStartEvent(encoding=self.use_encoding))
|
|
self.closed = False
|
|
elif self.closed:
|
|
raise SerializerError("serializer is closed")
|
|
else:
|
|
raise SerializerError("serializer is already opened")
|
|
|
|
def close(self):
|
|
if self.closed is None:
|
|
raise SerializerError("serializer is not opened")
|
|
elif not self.closed:
|
|
self.emit(StreamEndEvent())
|
|
self.closed = True
|
|
|
|
#def __del__(self):
|
|
# self.close()
|
|
|
|
def serialize(self, node):
|
|
if self.closed is None:
|
|
raise SerializerError("serializer is not opened")
|
|
elif self.closed:
|
|
raise SerializerError("serializer is closed")
|
|
self.emit(DocumentStartEvent(explicit=self.use_explicit_start,
|
|
version=self.use_version, tags=self.use_tags))
|
|
self.anchor_node(node)
|
|
self.serialize_node(node, None, None)
|
|
self.emit(DocumentEndEvent(explicit=self.use_explicit_end))
|
|
self.serialized_nodes = {}
|
|
self.anchors = {}
|
|
self.last_anchor_id = 0
|
|
|
|
def anchor_node(self, node):
|
|
if node in self.anchors:
|
|
if self.anchors[node] is None:
|
|
self.anchors[node] = self.generate_anchor(node)
|
|
else:
|
|
self.anchors[node] = None
|
|
if isinstance(node, SequenceNode):
|
|
for item in node.value:
|
|
self.anchor_node(item)
|
|
elif isinstance(node, MappingNode):
|
|
for key, value in node.value:
|
|
self.anchor_node(key)
|
|
self.anchor_node(value)
|
|
|
|
def generate_anchor(self, node):
|
|
self.last_anchor_id += 1
|
|
return self.ANCHOR_TEMPLATE % self.last_anchor_id
|
|
|
|
def serialize_node(self, node, parent, index):
|
|
alias = self.anchors[node]
|
|
if node in self.serialized_nodes:
|
|
self.emit(AliasEvent(alias))
|
|
else:
|
|
self.serialized_nodes[node] = True
|
|
self.descend_resolver(parent, index)
|
|
if isinstance(node, ScalarNode):
|
|
detected_tag = self.resolve(ScalarNode, node.value, (True, False))
|
|
default_tag = self.resolve(ScalarNode, node.value, (False, True))
|
|
implicit = (node.tag == detected_tag), (node.tag == default_tag)
|
|
self.emit(ScalarEvent(alias, node.tag, implicit, node.value,
|
|
style=node.style))
|
|
elif isinstance(node, SequenceNode):
|
|
implicit = (node.tag
|
|
== self.resolve(SequenceNode, node.value, True))
|
|
self.emit(SequenceStartEvent(alias, node.tag, implicit,
|
|
flow_style=node.flow_style))
|
|
index = 0
|
|
for item in node.value:
|
|
self.serialize_node(item, node, index)
|
|
index += 1
|
|
self.emit(SequenceEndEvent())
|
|
elif isinstance(node, MappingNode):
|
|
implicit = (node.tag
|
|
== self.resolve(MappingNode, node.value, True))
|
|
self.emit(MappingStartEvent(alias, node.tag, implicit,
|
|
flow_style=node.flow_style))
|
|
for key, value in node.value:
|
|
self.serialize_node(key, node, None)
|
|
self.serialize_node(value, node, key)
|
|
self.emit(MappingEndEvent())
|
|
self.ascend_resolver()
|
|
|