| |
| __all__ = ['BaseRepresenter', 'SafeRepresenter', 'Representer', |
| 'RepresenterError'] |
| |
| from error import * |
| from nodes import * |
| |
| import datetime |
| |
| import sys, copy_reg, types |
| |
| class RepresenterError(YAMLError): |
| pass |
| |
| class BaseRepresenter(object): |
| |
| yaml_representers = {} |
| yaml_multi_representers = {} |
| |
| def __init__(self, default_style=None, default_flow_style=None): |
| self.default_style = default_style |
| self.default_flow_style = default_flow_style |
| self.represented_objects = {} |
| self.object_keeper = [] |
| self.alias_key = None |
| |
| def represent(self, data): |
| node = self.represent_data(data) |
| self.serialize(node) |
| self.represented_objects = {} |
| self.object_keeper = [] |
| self.alias_key = None |
| |
| def get_classobj_bases(self, cls): |
| bases = [cls] |
| for base in cls.__bases__: |
| bases.extend(self.get_classobj_bases(base)) |
| return bases |
| |
| def represent_data(self, data): |
| if self.ignore_aliases(data): |
| self.alias_key = None |
| else: |
| self.alias_key = id(data) |
| if self.alias_key is not None: |
| if self.alias_key in self.represented_objects: |
| node = self.represented_objects[self.alias_key] |
| #if node is None: |
| # raise RepresenterError("recursive objects are not allowed: %r" % data) |
| return node |
| #self.represented_objects[alias_key] = None |
| self.object_keeper.append(data) |
| data_types = type(data).__mro__ |
| if type(data) is types.InstanceType: |
| data_types = self.get_classobj_bases(data.__class__)+list(data_types) |
| if data_types[0] in self.yaml_representers: |
| node = self.yaml_representers[data_types[0]](self, data) |
| else: |
| for data_type in data_types: |
| if data_type in self.yaml_multi_representers: |
| node = self.yaml_multi_representers[data_type](self, data) |
| break |
| else: |
| if None in self.yaml_multi_representers: |
| node = self.yaml_multi_representers[None](self, data) |
| elif None in self.yaml_representers: |
| node = self.yaml_representers[None](self, data) |
| else: |
| node = ScalarNode(None, unicode(data)) |
| #if alias_key is not None: |
| # self.represented_objects[alias_key] = node |
| return node |
| |
| def add_representer(cls, data_type, representer): |
| if not 'yaml_representers' in cls.__dict__: |
| cls.yaml_representers = cls.yaml_representers.copy() |
| cls.yaml_representers[data_type] = representer |
| add_representer = classmethod(add_representer) |
| |
| def add_multi_representer(cls, data_type, representer): |
| if not 'yaml_multi_representers' in cls.__dict__: |
| cls.yaml_multi_representers = cls.yaml_multi_representers.copy() |
| cls.yaml_multi_representers[data_type] = representer |
| add_multi_representer = classmethod(add_multi_representer) |
| |
| def represent_scalar(self, tag, value, style=None): |
| if style is None: |
| style = self.default_style |
| node = ScalarNode(tag, value, style=style) |
| if self.alias_key is not None: |
| self.represented_objects[self.alias_key] = node |
| return node |
| |
| def represent_sequence(self, tag, sequence, flow_style=None): |
| value = [] |
| node = SequenceNode(tag, value, flow_style=flow_style) |
| if self.alias_key is not None: |
| self.represented_objects[self.alias_key] = node |
| best_style = True |
| for item in sequence: |
| node_item = self.represent_data(item) |
| if not (isinstance(node_item, ScalarNode) and not node_item.style): |
| best_style = False |
| value.append(node_item) |
| if flow_style is None: |
| if self.default_flow_style is not None: |
| node.flow_style = self.default_flow_style |
| else: |
| node.flow_style = best_style |
| return node |
| |
| def represent_mapping(self, tag, mapping, flow_style=None): |
| value = [] |
| node = MappingNode(tag, value, flow_style=flow_style) |
| if self.alias_key is not None: |
| self.represented_objects[self.alias_key] = node |
| best_style = True |
| if hasattr(mapping, 'items'): |
| mapping = mapping.items() |
| mapping.sort() |
| for item_key, item_value in mapping: |
| node_key = self.represent_data(item_key) |
| node_value = self.represent_data(item_value) |
| if not (isinstance(node_key, ScalarNode) and not node_key.style): |
| best_style = False |
| if not (isinstance(node_value, ScalarNode) and not node_value.style): |
| best_style = False |
| value.append((node_key, node_value)) |
| if flow_style is None: |
| if self.default_flow_style is not None: |
| node.flow_style = self.default_flow_style |
| else: |
| node.flow_style = best_style |
| return node |
| |
| def ignore_aliases(self, data): |
| return False |
| |
| class SafeRepresenter(BaseRepresenter): |
| |
| def ignore_aliases(self, data): |
| if data is None: |
| return True |
| if isinstance(data, tuple) and data == (): |
| return True |
| if isinstance(data, (str, unicode, bool, int, float)): |
| return True |
| |
| def represent_none(self, data): |
| return self.represent_scalar(u'tag:yaml.org,2002:null', |
| u'null') |
| |
| def represent_str(self, data): |
| tag = None |
| style = None |
| try: |
| data = unicode(data, 'ascii') |
| tag = u'tag:yaml.org,2002:str' |
| except UnicodeDecodeError: |
| try: |
| data = unicode(data, 'utf-8') |
| tag = u'tag:yaml.org,2002:str' |
| except UnicodeDecodeError: |
| data = data.encode('base64') |
| tag = u'tag:yaml.org,2002:binary' |
| style = '|' |
| return self.represent_scalar(tag, data, style=style) |
| |
| def represent_unicode(self, data): |
| return self.represent_scalar(u'tag:yaml.org,2002:str', data) |
| |
| def represent_bool(self, data): |
| if data: |
| value = u'true' |
| else: |
| value = u'false' |
| return self.represent_scalar(u'tag:yaml.org,2002:bool', value) |
| |
| def represent_int(self, data): |
| return self.represent_scalar(u'tag:yaml.org,2002:int', unicode(data)) |
| |
| def represent_long(self, data): |
| return self.represent_scalar(u'tag:yaml.org,2002:int', unicode(data)) |
| |
| inf_value = 1e300 |
| while repr(inf_value) != repr(inf_value*inf_value): |
| inf_value *= inf_value |
| |
| def represent_float(self, data): |
| if data != data or (data == 0.0 and data == 1.0): |
| value = u'.nan' |
| elif data == self.inf_value: |
| value = u'.inf' |
| elif data == -self.inf_value: |
| value = u'-.inf' |
| else: |
| value = unicode(repr(data)).lower() |
| # Note that in some cases `repr(data)` represents a float number |
| # without the decimal parts. For instance: |
| # >>> repr(1e17) |
| # '1e17' |
| # Unfortunately, this is not a valid float representation according |
| # to the definition of the `!!float` tag. We fix this by adding |
| # '.0' before the 'e' symbol. |
| if u'.' not in value and u'e' in value: |
| value = value.replace(u'e', u'.0e', 1) |
| return self.represent_scalar(u'tag:yaml.org,2002:float', value) |
| |
| def represent_list(self, data): |
| #pairs = (len(data) > 0 and isinstance(data, list)) |
| #if pairs: |
| # for item in data: |
| # if not isinstance(item, tuple) or len(item) != 2: |
| # pairs = False |
| # break |
| #if not pairs: |
| return self.represent_sequence(u'tag:yaml.org,2002:seq', data) |
| #value = [] |
| #for item_key, item_value in data: |
| # value.append(self.represent_mapping(u'tag:yaml.org,2002:map', |
| # [(item_key, item_value)])) |
| #return SequenceNode(u'tag:yaml.org,2002:pairs', value) |
| |
| def represent_dict(self, data): |
| return self.represent_mapping(u'tag:yaml.org,2002:map', data) |
| |
| def represent_set(self, data): |
| value = {} |
| for key in data: |
| value[key] = None |
| return self.represent_mapping(u'tag:yaml.org,2002:set', value) |
| |
| def represent_date(self, data): |
| value = unicode(data.isoformat()) |
| return self.represent_scalar(u'tag:yaml.org,2002:timestamp', value) |
| |
| def represent_datetime(self, data): |
| value = unicode(data.isoformat(' ')) |
| return self.represent_scalar(u'tag:yaml.org,2002:timestamp', value) |
| |
| def represent_yaml_object(self, tag, data, cls, flow_style=None): |
| if hasattr(data, '__getstate__'): |
| state = data.__getstate__() |
| else: |
| state = data.__dict__.copy() |
| return self.represent_mapping(tag, state, flow_style=flow_style) |
| |
| def represent_undefined(self, data): |
| raise RepresenterError("cannot represent an object", data) |
| |
| SafeRepresenter.add_representer(type(None), |
| SafeRepresenter.represent_none) |
| |
| SafeRepresenter.add_representer(str, |
| SafeRepresenter.represent_str) |
| |
| SafeRepresenter.add_representer(unicode, |
| SafeRepresenter.represent_unicode) |
| |
| SafeRepresenter.add_representer(bool, |
| SafeRepresenter.represent_bool) |
| |
| SafeRepresenter.add_representer(int, |
| SafeRepresenter.represent_int) |
| |
| SafeRepresenter.add_representer(long, |
| SafeRepresenter.represent_long) |
| |
| SafeRepresenter.add_representer(float, |
| SafeRepresenter.represent_float) |
| |
| SafeRepresenter.add_representer(list, |
| SafeRepresenter.represent_list) |
| |
| SafeRepresenter.add_representer(tuple, |
| SafeRepresenter.represent_list) |
| |
| SafeRepresenter.add_representer(dict, |
| SafeRepresenter.represent_dict) |
| |
| SafeRepresenter.add_representer(set, |
| SafeRepresenter.represent_set) |
| |
| SafeRepresenter.add_representer(datetime.date, |
| SafeRepresenter.represent_date) |
| |
| SafeRepresenter.add_representer(datetime.datetime, |
| SafeRepresenter.represent_datetime) |
| |
| SafeRepresenter.add_representer(None, |
| SafeRepresenter.represent_undefined) |
| |
| class Representer(SafeRepresenter): |
| |
| def represent_str(self, data): |
| tag = None |
| style = None |
| try: |
| data = unicode(data, 'ascii') |
| tag = u'tag:yaml.org,2002:str' |
| except UnicodeDecodeError: |
| try: |
| data = unicode(data, 'utf-8') |
| tag = u'tag:yaml.org,2002:python/str' |
| except UnicodeDecodeError: |
| data = data.encode('base64') |
| tag = u'tag:yaml.org,2002:binary' |
| style = '|' |
| return self.represent_scalar(tag, data, style=style) |
| |
| def represent_unicode(self, data): |
| tag = None |
| try: |
| data.encode('ascii') |
| tag = u'tag:yaml.org,2002:python/unicode' |
| except UnicodeEncodeError: |
| tag = u'tag:yaml.org,2002:str' |
| return self.represent_scalar(tag, data) |
| |
| def represent_long(self, data): |
| tag = u'tag:yaml.org,2002:int' |
| if int(data) is not data: |
| tag = u'tag:yaml.org,2002:python/long' |
| return self.represent_scalar(tag, unicode(data)) |
| |
| def represent_complex(self, data): |
| if data.imag == 0.0: |
| data = u'%r' % data.real |
| elif data.real == 0.0: |
| data = u'%rj' % data.imag |
| elif data.imag > 0: |
| data = u'%r+%rj' % (data.real, data.imag) |
| else: |
| data = u'%r%rj' % (data.real, data.imag) |
| return self.represent_scalar(u'tag:yaml.org,2002:python/complex', data) |
| |
| def represent_tuple(self, data): |
| return self.represent_sequence(u'tag:yaml.org,2002:python/tuple', data) |
| |
| def represent_name(self, data): |
| name = u'%s.%s' % (data.__module__, data.__name__) |
| return self.represent_scalar(u'tag:yaml.org,2002:python/name:'+name, u'') |
| |
| def represent_module(self, data): |
| return self.represent_scalar( |
| u'tag:yaml.org,2002:python/module:'+data.__name__, u'') |
| |
| def represent_instance(self, data): |
| # For instances of classic classes, we use __getinitargs__ and |
| # __getstate__ to serialize the data. |
| |
| # If data.__getinitargs__ exists, the object must be reconstructed by |
| # calling cls(**args), where args is a tuple returned by |
| # __getinitargs__. Otherwise, the cls.__init__ method should never be |
| # called and the class instance is created by instantiating a trivial |
| # class and assigning to the instance's __class__ variable. |
| |
| # If data.__getstate__ exists, it returns the state of the object. |
| # Otherwise, the state of the object is data.__dict__. |
| |
| # We produce either a !!python/object or !!python/object/new node. |
| # If data.__getinitargs__ does not exist and state is a dictionary, we |
| # produce a !!python/object node . Otherwise we produce a |
| # !!python/object/new node. |
| |
| cls = data.__class__ |
| class_name = u'%s.%s' % (cls.__module__, cls.__name__) |
| args = None |
| state = None |
| if hasattr(data, '__getinitargs__'): |
| args = list(data.__getinitargs__()) |
| if hasattr(data, '__getstate__'): |
| state = data.__getstate__() |
| else: |
| state = data.__dict__ |
| if args is None and isinstance(state, dict): |
| return self.represent_mapping( |
| u'tag:yaml.org,2002:python/object:'+class_name, state) |
| if isinstance(state, dict) and not state: |
| return self.represent_sequence( |
| u'tag:yaml.org,2002:python/object/new:'+class_name, args) |
| value = {} |
| if args: |
| value['args'] = args |
| value['state'] = state |
| return self.represent_mapping( |
| u'tag:yaml.org,2002:python/object/new:'+class_name, value) |
| |
| def represent_object(self, data): |
| # We use __reduce__ API to save the data. data.__reduce__ returns |
| # a tuple of length 2-5: |
| # (function, args, state, listitems, dictitems) |
| |
| # For reconstructing, we calls function(*args), then set its state, |
| # listitems, and dictitems if they are not None. |
| |
| # A special case is when function.__name__ == '__newobj__'. In this |
| # case we create the object with args[0].__new__(*args). |
| |
| # Another special case is when __reduce__ returns a string - we don't |
| # support it. |
| |
| # We produce a !!python/object, !!python/object/new or |
| # !!python/object/apply node. |
| |
| cls = type(data) |
| if cls in copy_reg.dispatch_table: |
| reduce = copy_reg.dispatch_table[cls](data) |
| elif hasattr(data, '__reduce_ex__'): |
| reduce = data.__reduce_ex__(2) |
| elif hasattr(data, '__reduce__'): |
| reduce = data.__reduce__() |
| else: |
| raise RepresenterError("cannot represent an object", data) |
| reduce = (list(reduce)+[None]*5)[:5] |
| function, args, state, listitems, dictitems = reduce |
| args = list(args) |
| if state is None: |
| state = {} |
| if listitems is not None: |
| listitems = list(listitems) |
| if dictitems is not None: |
| dictitems = dict(dictitems) |
| if function.__name__ == '__newobj__': |
| function = args[0] |
| args = args[1:] |
| tag = u'tag:yaml.org,2002:python/object/new:' |
| newobj = True |
| else: |
| tag = u'tag:yaml.org,2002:python/object/apply:' |
| newobj = False |
| function_name = u'%s.%s' % (function.__module__, function.__name__) |
| if not args and not listitems and not dictitems \ |
| and isinstance(state, dict) and newobj: |
| return self.represent_mapping( |
| u'tag:yaml.org,2002:python/object:'+function_name, state) |
| if not listitems and not dictitems \ |
| and isinstance(state, dict) and not state: |
| return self.represent_sequence(tag+function_name, args) |
| value = {} |
| if args: |
| value['args'] = args |
| if state or not isinstance(state, dict): |
| value['state'] = state |
| if listitems: |
| value['listitems'] = listitems |
| if dictitems: |
| value['dictitems'] = dictitems |
| return self.represent_mapping(tag+function_name, value) |
| |
| Representer.add_representer(str, |
| Representer.represent_str) |
| |
| Representer.add_representer(unicode, |
| Representer.represent_unicode) |
| |
| Representer.add_representer(long, |
| Representer.represent_long) |
| |
| Representer.add_representer(complex, |
| Representer.represent_complex) |
| |
| Representer.add_representer(tuple, |
| Representer.represent_tuple) |
| |
| Representer.add_representer(type, |
| Representer.represent_name) |
| |
| Representer.add_representer(types.ClassType, |
| Representer.represent_name) |
| |
| Representer.add_representer(types.FunctionType, |
| Representer.represent_name) |
| |
| Representer.add_representer(types.BuiltinFunctionType, |
| Representer.represent_name) |
| |
| Representer.add_representer(types.ModuleType, |
| Representer.represent_module) |
| |
| Representer.add_multi_representer(types.InstanceType, |
| Representer.represent_instance) |
| |
| Representer.add_multi_representer(object, |
| Representer.represent_object) |
| |
