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-rw-r--r--python/pyyaml/lib/yaml/constructor.py675
1 files changed, 675 insertions, 0 deletions
diff --git a/python/pyyaml/lib/yaml/constructor.py b/python/pyyaml/lib/yaml/constructor.py
new file mode 100644
index 000000000..635faac3e
--- /dev/null
+++ b/python/pyyaml/lib/yaml/constructor.py
@@ -0,0 +1,675 @@
+
+__all__ = ['BaseConstructor', 'SafeConstructor', 'Constructor',
+ 'ConstructorError']
+
+from error import *
+from nodes import *
+
+import datetime
+
+import binascii, re, sys, types
+
+class ConstructorError(MarkedYAMLError):
+ pass
+
+class BaseConstructor(object):
+
+ yaml_constructors = {}
+ yaml_multi_constructors = {}
+
+ def __init__(self):
+ self.constructed_objects = {}
+ self.recursive_objects = {}
+ self.state_generators = []
+ self.deep_construct = False
+
+ def check_data(self):
+ # If there are more documents available?
+ return self.check_node()
+
+ def get_data(self):
+ # Construct and return the next document.
+ if self.check_node():
+ return self.construct_document(self.get_node())
+
+ def get_single_data(self):
+ # Ensure that the stream contains a single document and construct it.
+ node = self.get_single_node()
+ if node is not None:
+ return self.construct_document(node)
+ return None
+
+ def construct_document(self, node):
+ data = self.construct_object(node)
+ while self.state_generators:
+ state_generators = self.state_generators
+ self.state_generators = []
+ for generator in state_generators:
+ for dummy in generator:
+ pass
+ self.constructed_objects = {}
+ self.recursive_objects = {}
+ self.deep_construct = False
+ return data
+
+ def construct_object(self, node, deep=False):
+ if node in self.constructed_objects:
+ return self.constructed_objects[node]
+ if deep:
+ old_deep = self.deep_construct
+ self.deep_construct = True
+ if node in self.recursive_objects:
+ raise ConstructorError(None, None,
+ "found unconstructable recursive node", node.start_mark)
+ self.recursive_objects[node] = None
+ constructor = None
+ tag_suffix = None
+ if node.tag in self.yaml_constructors:
+ constructor = self.yaml_constructors[node.tag]
+ else:
+ for tag_prefix in self.yaml_multi_constructors:
+ if node.tag.startswith(tag_prefix):
+ tag_suffix = node.tag[len(tag_prefix):]
+ constructor = self.yaml_multi_constructors[tag_prefix]
+ break
+ else:
+ if None in self.yaml_multi_constructors:
+ tag_suffix = node.tag
+ constructor = self.yaml_multi_constructors[None]
+ elif None in self.yaml_constructors:
+ constructor = self.yaml_constructors[None]
+ elif isinstance(node, ScalarNode):
+ constructor = self.__class__.construct_scalar
+ elif isinstance(node, SequenceNode):
+ constructor = self.__class__.construct_sequence
+ elif isinstance(node, MappingNode):
+ constructor = self.__class__.construct_mapping
+ if tag_suffix is None:
+ data = constructor(self, node)
+ else:
+ data = constructor(self, tag_suffix, node)
+ if isinstance(data, types.GeneratorType):
+ generator = data
+ data = generator.next()
+ if self.deep_construct:
+ for dummy in generator:
+ pass
+ else:
+ self.state_generators.append(generator)
+ self.constructed_objects[node] = data
+ del self.recursive_objects[node]
+ if deep:
+ self.deep_construct = old_deep
+ return data
+
+ def construct_scalar(self, node):
+ if not isinstance(node, ScalarNode):
+ raise ConstructorError(None, None,
+ "expected a scalar node, but found %s" % node.id,
+ node.start_mark)
+ return node.value
+
+ def construct_sequence(self, node, deep=False):
+ if not isinstance(node, SequenceNode):
+ raise ConstructorError(None, None,
+ "expected a sequence node, but found %s" % node.id,
+ node.start_mark)
+ return [self.construct_object(child, deep=deep)
+ for child in node.value]
+
+ def construct_mapping(self, node, deep=False):
+ if not isinstance(node, MappingNode):
+ raise ConstructorError(None, None,
+ "expected a mapping node, but found %s" % node.id,
+ node.start_mark)
+ mapping = {}
+ for key_node, value_node in node.value:
+ key = self.construct_object(key_node, deep=deep)
+ try:
+ hash(key)
+ except TypeError, exc:
+ raise ConstructorError("while constructing a mapping", node.start_mark,
+ "found unacceptable key (%s)" % exc, key_node.start_mark)
+ value = self.construct_object(value_node, deep=deep)
+ mapping[key] = value
+ return mapping
+
+ def construct_pairs(self, node, deep=False):
+ if not isinstance(node, MappingNode):
+ raise ConstructorError(None, None,
+ "expected a mapping node, but found %s" % node.id,
+ node.start_mark)
+ pairs = []
+ for key_node, value_node in node.value:
+ key = self.construct_object(key_node, deep=deep)
+ value = self.construct_object(value_node, deep=deep)
+ pairs.append((key, value))
+ return pairs
+
+ def add_constructor(cls, tag, constructor):
+ if not 'yaml_constructors' in cls.__dict__:
+ cls.yaml_constructors = cls.yaml_constructors.copy()
+ cls.yaml_constructors[tag] = constructor
+ add_constructor = classmethod(add_constructor)
+
+ def add_multi_constructor(cls, tag_prefix, multi_constructor):
+ if not 'yaml_multi_constructors' in cls.__dict__:
+ cls.yaml_multi_constructors = cls.yaml_multi_constructors.copy()
+ cls.yaml_multi_constructors[tag_prefix] = multi_constructor
+ add_multi_constructor = classmethod(add_multi_constructor)
+
+class SafeConstructor(BaseConstructor):
+
+ def construct_scalar(self, node):
+ if isinstance(node, MappingNode):
+ for key_node, value_node in node.value:
+ if key_node.tag == u'tag:yaml.org,2002:value':
+ return self.construct_scalar(value_node)
+ return BaseConstructor.construct_scalar(self, node)
+
+ def flatten_mapping(self, node):
+ merge = []
+ index = 0
+ while index < len(node.value):
+ key_node, value_node = node.value[index]
+ if key_node.tag == u'tag:yaml.org,2002:merge':
+ del node.value[index]
+ if isinstance(value_node, MappingNode):
+ self.flatten_mapping(value_node)
+ merge.extend(value_node.value)
+ elif isinstance(value_node, SequenceNode):
+ submerge = []
+ for subnode in value_node.value:
+ if not isinstance(subnode, MappingNode):
+ raise ConstructorError("while constructing a mapping",
+ node.start_mark,
+ "expected a mapping for merging, but found %s"
+ % subnode.id, subnode.start_mark)
+ self.flatten_mapping(subnode)
+ submerge.append(subnode.value)
+ submerge.reverse()
+ for value in submerge:
+ merge.extend(value)
+ else:
+ raise ConstructorError("while constructing a mapping", node.start_mark,
+ "expected a mapping or list of mappings for merging, but found %s"
+ % value_node.id, value_node.start_mark)
+ elif key_node.tag == u'tag:yaml.org,2002:value':
+ key_node.tag = u'tag:yaml.org,2002:str'
+ index += 1
+ else:
+ index += 1
+ if merge:
+ node.value = merge + node.value
+
+ def construct_mapping(self, node, deep=False):
+ if isinstance(node, MappingNode):
+ self.flatten_mapping(node)
+ return BaseConstructor.construct_mapping(self, node, deep=deep)
+
+ def construct_yaml_null(self, node):
+ self.construct_scalar(node)
+ return None
+
+ bool_values = {
+ u'yes': True,
+ u'no': False,
+ u'true': True,
+ u'false': False,
+ u'on': True,
+ u'off': False,
+ }
+
+ def construct_yaml_bool(self, node):
+ value = self.construct_scalar(node)
+ return self.bool_values[value.lower()]
+
+ def construct_yaml_int(self, node):
+ value = str(self.construct_scalar(node))
+ value = value.replace('_', '')
+ sign = +1
+ if value[0] == '-':
+ sign = -1
+ if value[0] in '+-':
+ value = value[1:]
+ if value == '0':
+ return 0
+ elif value.startswith('0b'):
+ return sign*int(value[2:], 2)
+ elif value.startswith('0x'):
+ return sign*int(value[2:], 16)
+ elif value[0] == '0':
+ return sign*int(value, 8)
+ elif ':' in value:
+ digits = [int(part) for part in value.split(':')]
+ digits.reverse()
+ base = 1
+ value = 0
+ for digit in digits:
+ value += digit*base
+ base *= 60
+ return sign*value
+ else:
+ return sign*int(value)
+
+ inf_value = 1e300
+ while inf_value != inf_value*inf_value:
+ inf_value *= inf_value
+ nan_value = -inf_value/inf_value # Trying to make a quiet NaN (like C99).
+
+ def construct_yaml_float(self, node):
+ value = str(self.construct_scalar(node))
+ value = value.replace('_', '').lower()
+ sign = +1
+ if value[0] == '-':
+ sign = -1
+ if value[0] in '+-':
+ value = value[1:]
+ if value == '.inf':
+ return sign*self.inf_value
+ elif value == '.nan':
+ return self.nan_value
+ elif ':' in value:
+ digits = [float(part) for part in value.split(':')]
+ digits.reverse()
+ base = 1
+ value = 0.0
+ for digit in digits:
+ value += digit*base
+ base *= 60
+ return sign*value
+ else:
+ return sign*float(value)
+
+ def construct_yaml_binary(self, node):
+ value = self.construct_scalar(node)
+ try:
+ return str(value).decode('base64')
+ except (binascii.Error, UnicodeEncodeError), exc:
+ raise ConstructorError(None, None,
+ "failed to decode base64 data: %s" % exc, node.start_mark)
+
+ timestamp_regexp = re.compile(
+ ur'''^(?P<year>[0-9][0-9][0-9][0-9])
+ -(?P<month>[0-9][0-9]?)
+ -(?P<day>[0-9][0-9]?)
+ (?:(?:[Tt]|[ \t]+)
+ (?P<hour>[0-9][0-9]?)
+ :(?P<minute>[0-9][0-9])
+ :(?P<second>[0-9][0-9])
+ (?:\.(?P<fraction>[0-9]*))?
+ (?:[ \t]*(?P<tz>Z|(?P<tz_sign>[-+])(?P<tz_hour>[0-9][0-9]?)
+ (?::(?P<tz_minute>[0-9][0-9]))?))?)?$''', re.X)
+
+ def construct_yaml_timestamp(self, node):
+ value = self.construct_scalar(node)
+ match = self.timestamp_regexp.match(node.value)
+ values = match.groupdict()
+ year = int(values['year'])
+ month = int(values['month'])
+ day = int(values['day'])
+ if not values['hour']:
+ return datetime.date(year, month, day)
+ hour = int(values['hour'])
+ minute = int(values['minute'])
+ second = int(values['second'])
+ fraction = 0
+ if values['fraction']:
+ fraction = values['fraction'][:6]
+ while len(fraction) < 6:
+ fraction += '0'
+ fraction = int(fraction)
+ delta = None
+ if values['tz_sign']:
+ tz_hour = int(values['tz_hour'])
+ tz_minute = int(values['tz_minute'] or 0)
+ delta = datetime.timedelta(hours=tz_hour, minutes=tz_minute)
+ if values['tz_sign'] == '-':
+ delta = -delta
+ data = datetime.datetime(year, month, day, hour, minute, second, fraction)
+ if delta:
+ data -= delta
+ return data
+
+ def construct_yaml_omap(self, node):
+ # Note: we do not check for duplicate keys, because it's too
+ # CPU-expensive.
+ omap = []
+ yield omap
+ if not isinstance(node, SequenceNode):
+ raise ConstructorError("while constructing an ordered map", node.start_mark,
+ "expected a sequence, but found %s" % node.id, node.start_mark)
+ for subnode in node.value:
+ if not isinstance(subnode, MappingNode):
+ raise ConstructorError("while constructing an ordered map", node.start_mark,
+ "expected a mapping of length 1, but found %s" % subnode.id,
+ subnode.start_mark)
+ if len(subnode.value) != 1:
+ raise ConstructorError("while constructing an ordered map", node.start_mark,
+ "expected a single mapping item, but found %d items" % len(subnode.value),
+ subnode.start_mark)
+ key_node, value_node = subnode.value[0]
+ key = self.construct_object(key_node)
+ value = self.construct_object(value_node)
+ omap.append((key, value))
+
+ def construct_yaml_pairs(self, node):
+ # Note: the same code as `construct_yaml_omap`.
+ pairs = []
+ yield pairs
+ if not isinstance(node, SequenceNode):
+ raise ConstructorError("while constructing pairs", node.start_mark,
+ "expected a sequence, but found %s" % node.id, node.start_mark)
+ for subnode in node.value:
+ if not isinstance(subnode, MappingNode):
+ raise ConstructorError("while constructing pairs", node.start_mark,
+ "expected a mapping of length 1, but found %s" % subnode.id,
+ subnode.start_mark)
+ if len(subnode.value) != 1:
+ raise ConstructorError("while constructing pairs", node.start_mark,
+ "expected a single mapping item, but found %d items" % len(subnode.value),
+ subnode.start_mark)
+ key_node, value_node = subnode.value[0]
+ key = self.construct_object(key_node)
+ value = self.construct_object(value_node)
+ pairs.append((key, value))
+
+ def construct_yaml_set(self, node):
+ data = set()
+ yield data
+ value = self.construct_mapping(node)
+ data.update(value)
+
+ def construct_yaml_str(self, node):
+ value = self.construct_scalar(node)
+ try:
+ return value.encode('ascii')
+ except UnicodeEncodeError:
+ return value
+
+ def construct_yaml_seq(self, node):
+ data = []
+ yield data
+ data.extend(self.construct_sequence(node))
+
+ def construct_yaml_map(self, node):
+ data = {}
+ yield data
+ value = self.construct_mapping(node)
+ data.update(value)
+
+ def construct_yaml_object(self, node, cls):
+ data = cls.__new__(cls)
+ yield data
+ if hasattr(data, '__setstate__'):
+ state = self.construct_mapping(node, deep=True)
+ data.__setstate__(state)
+ else:
+ state = self.construct_mapping(node)
+ data.__dict__.update(state)
+
+ def construct_undefined(self, node):
+ raise ConstructorError(None, None,
+ "could not determine a constructor for the tag %r" % node.tag.encode('utf-8'),
+ node.start_mark)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:null',
+ SafeConstructor.construct_yaml_null)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:bool',
+ SafeConstructor.construct_yaml_bool)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:int',
+ SafeConstructor.construct_yaml_int)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:float',
+ SafeConstructor.construct_yaml_float)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:binary',
+ SafeConstructor.construct_yaml_binary)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:timestamp',
+ SafeConstructor.construct_yaml_timestamp)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:omap',
+ SafeConstructor.construct_yaml_omap)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:pairs',
+ SafeConstructor.construct_yaml_pairs)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:set',
+ SafeConstructor.construct_yaml_set)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:str',
+ SafeConstructor.construct_yaml_str)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:seq',
+ SafeConstructor.construct_yaml_seq)
+
+SafeConstructor.add_constructor(
+ u'tag:yaml.org,2002:map',
+ SafeConstructor.construct_yaml_map)
+
+SafeConstructor.add_constructor(None,
+ SafeConstructor.construct_undefined)
+
+class Constructor(SafeConstructor):
+
+ def construct_python_str(self, node):
+ return self.construct_scalar(node).encode('utf-8')
+
+ def construct_python_unicode(self, node):
+ return self.construct_scalar(node)
+
+ def construct_python_long(self, node):
+ return long(self.construct_yaml_int(node))
+
+ def construct_python_complex(self, node):
+ return complex(self.construct_scalar(node))
+
+ def construct_python_tuple(self, node):
+ return tuple(self.construct_sequence(node))
+
+ def find_python_module(self, name, mark):
+ if not name:
+ raise ConstructorError("while constructing a Python module", mark,
+ "expected non-empty name appended to the tag", mark)
+ try:
+ __import__(name)
+ except ImportError, exc:
+ raise ConstructorError("while constructing a Python module", mark,
+ "cannot find module %r (%s)" % (name.encode('utf-8'), exc), mark)
+ return sys.modules[name]
+
+ def find_python_name(self, name, mark):
+ if not name:
+ raise ConstructorError("while constructing a Python object", mark,
+ "expected non-empty name appended to the tag", mark)
+ if u'.' in name:
+ module_name, object_name = name.rsplit('.', 1)
+ else:
+ module_name = '__builtin__'
+ object_name = name
+ try:
+ __import__(module_name)
+ except ImportError, exc:
+ raise ConstructorError("while constructing a Python object", mark,
+ "cannot find module %r (%s)" % (module_name.encode('utf-8'), exc), mark)
+ module = sys.modules[module_name]
+ if not hasattr(module, object_name):
+ raise ConstructorError("while constructing a Python object", mark,
+ "cannot find %r in the module %r" % (object_name.encode('utf-8'),
+ module.__name__), mark)
+ return getattr(module, object_name)
+
+ def construct_python_name(self, suffix, node):
+ value = self.construct_scalar(node)
+ if value:
+ raise ConstructorError("while constructing a Python name", node.start_mark,
+ "expected the empty value, but found %r" % value.encode('utf-8'),
+ node.start_mark)
+ return self.find_python_name(suffix, node.start_mark)
+
+ def construct_python_module(self, suffix, node):
+ value = self.construct_scalar(node)
+ if value:
+ raise ConstructorError("while constructing a Python module", node.start_mark,
+ "expected the empty value, but found %r" % value.encode('utf-8'),
+ node.start_mark)
+ return self.find_python_module(suffix, node.start_mark)
+
+ class classobj: pass
+
+ def make_python_instance(self, suffix, node,
+ args=None, kwds=None, newobj=False):
+ if not args:
+ args = []
+ if not kwds:
+ kwds = {}
+ cls = self.find_python_name(suffix, node.start_mark)
+ if newobj and isinstance(cls, type(self.classobj)) \
+ and not args and not kwds:
+ instance = self.classobj()
+ instance.__class__ = cls
+ return instance
+ elif newobj and isinstance(cls, type):
+ return cls.__new__(cls, *args, **kwds)
+ else:
+ return cls(*args, **kwds)
+
+ def set_python_instance_state(self, instance, state):
+ if hasattr(instance, '__setstate__'):
+ instance.__setstate__(state)
+ else:
+ slotstate = {}
+ if isinstance(state, tuple) and len(state) == 2:
+ state, slotstate = state
+ if hasattr(instance, '__dict__'):
+ instance.__dict__.update(state)
+ elif state:
+ slotstate.update(state)
+ for key, value in slotstate.items():
+ setattr(object, key, value)
+
+ def construct_python_object(self, suffix, node):
+ # Format:
+ # !!python/object:module.name { ... state ... }
+ instance = self.make_python_instance(suffix, node, newobj=True)
+ yield instance
+ deep = hasattr(instance, '__setstate__')
+ state = self.construct_mapping(node, deep=deep)
+ self.set_python_instance_state(instance, state)
+
+ def construct_python_object_apply(self, suffix, node, newobj=False):
+ # Format:
+ # !!python/object/apply # (or !!python/object/new)
+ # args: [ ... arguments ... ]
+ # kwds: { ... keywords ... }
+ # state: ... state ...
+ # listitems: [ ... listitems ... ]
+ # dictitems: { ... dictitems ... }
+ # or short format:
+ # !!python/object/apply [ ... arguments ... ]
+ # The difference between !!python/object/apply and !!python/object/new
+ # is how an object is created, check make_python_instance for details.
+ if isinstance(node, SequenceNode):
+ args = self.construct_sequence(node, deep=True)
+ kwds = {}
+ state = {}
+ listitems = []
+ dictitems = {}
+ else:
+ value = self.construct_mapping(node, deep=True)
+ args = value.get('args', [])
+ kwds = value.get('kwds', {})
+ state = value.get('state', {})
+ listitems = value.get('listitems', [])
+ dictitems = value.get('dictitems', {})
+ instance = self.make_python_instance(suffix, node, args, kwds, newobj)
+ if state:
+ self.set_python_instance_state(instance, state)
+ if listitems:
+ instance.extend(listitems)
+ if dictitems:
+ for key in dictitems:
+ instance[key] = dictitems[key]
+ return instance
+
+ def construct_python_object_new(self, suffix, node):
+ return self.construct_python_object_apply(suffix, node, newobj=True)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/none',
+ Constructor.construct_yaml_null)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/bool',
+ Constructor.construct_yaml_bool)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/str',
+ Constructor.construct_python_str)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/unicode',
+ Constructor.construct_python_unicode)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/int',
+ Constructor.construct_yaml_int)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/long',
+ Constructor.construct_python_long)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/float',
+ Constructor.construct_yaml_float)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/complex',
+ Constructor.construct_python_complex)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/list',
+ Constructor.construct_yaml_seq)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/tuple',
+ Constructor.construct_python_tuple)
+
+Constructor.add_constructor(
+ u'tag:yaml.org,2002:python/dict',
+ Constructor.construct_yaml_map)
+
+Constructor.add_multi_constructor(
+ u'tag:yaml.org,2002:python/name:',
+ Constructor.construct_python_name)
+
+Constructor.add_multi_constructor(
+ u'tag:yaml.org,2002:python/module:',
+ Constructor.construct_python_module)
+
+Constructor.add_multi_constructor(
+ u'tag:yaml.org,2002:python/object:',
+ Constructor.construct_python_object)
+
+Constructor.add_multi_constructor(
+ u'tag:yaml.org,2002:python/object/apply:',
+ Constructor.construct_python_object_apply)
+
+Constructor.add_multi_constructor(
+ u'tag:yaml.org,2002:python/object/new:',
+ Constructor.construct_python_object_new)
+