Aluode/PerceptionLabPortable

1 2__all__ = ['BaseRepresenter', 'SafeRepresenter', 'Representer',3    'RepresenterError']4 5from .error import *6from .nodes import *7 8import datetime, copyreg, types, base64, collections9 10class RepresenterError(YAMLError):11    pass12 13class BaseRepresenter:14 15    yaml_representers = {}16    yaml_multi_representers = {}17 18    def __init__(self, default_style=None, default_flow_style=False, sort_keys=True):19        self.default_style = default_style20        self.sort_keys = sort_keys21        self.default_flow_style = default_flow_style22        self.represented_objects = {}23        self.object_keeper = []24        self.alias_key = None25 26    def represent(self, data):27        node = self.represent_data(data)28        self.serialize(node)29        self.represented_objects = {}30        self.object_keeper = []31        self.alias_key = None32 33    def represent_data(self, data):34        if self.ignore_aliases(data):35            self.alias_key = None36        else:37            self.alias_key = id(data)38        if self.alias_key is not None:39            if self.alias_key in self.represented_objects:40                node = self.represented_objects[self.alias_key]41                #if node is None:42                #    raise RepresenterError("recursive objects are not allowed: %r" % data)43                return node44            #self.represented_objects[alias_key] = None45            self.object_keeper.append(data)46        data_types = type(data).__mro__47        if data_types[0] in self.yaml_representers:48            node = self.yaml_representers[data_types[0]](self, data)49        else:50            for data_type in data_types:51                if data_type in self.yaml_multi_representers:52                    node = self.yaml_multi_representers[data_type](self, data)53                    break54            else:55                if None in self.yaml_multi_representers:56                    node = self.yaml_multi_representers[None](self, data)57                elif None in self.yaml_representers:58                    node = self.yaml_representers[None](self, data)59                else:60                    node = ScalarNode(None, str(data))61        #if alias_key is not None:62        #    self.represented_objects[alias_key] = node63        return node64 65    @classmethod66    def add_representer(cls, data_type, representer):67        if not 'yaml_representers' in cls.__dict__:68            cls.yaml_representers = cls.yaml_representers.copy()69        cls.yaml_representers[data_type] = representer70 71    @classmethod72    def add_multi_representer(cls, data_type, representer):73        if not 'yaml_multi_representers' in cls.__dict__:74            cls.yaml_multi_representers = cls.yaml_multi_representers.copy()75        cls.yaml_multi_representers[data_type] = representer76 77    def represent_scalar(self, tag, value, style=None):78        if style is None:79            style = self.default_style80        node = ScalarNode(tag, value, style=style)81        if self.alias_key is not None:82            self.represented_objects[self.alias_key] = node83        return node84 85    def represent_sequence(self, tag, sequence, flow_style=None):86        value = []87        node = SequenceNode(tag, value, flow_style=flow_style)88        if self.alias_key is not None:89            self.represented_objects[self.alias_key] = node90        best_style = True91        for item in sequence:92            node_item = self.represent_data(item)93            if not (isinstance(node_item, ScalarNode) and not node_item.style):94                best_style = False95            value.append(node_item)96        if flow_style is None:97            if self.default_flow_style is not None:98                node.flow_style = self.default_flow_style99            else:100                node.flow_style = best_style101        return node102 103    def represent_mapping(self, tag, mapping, flow_style=None):104        value = []105        node = MappingNode(tag, value, flow_style=flow_style)106        if self.alias_key is not None:107            self.represented_objects[self.alias_key] = node108        best_style = True109        if hasattr(mapping, 'items'):110            mapping = list(mapping.items())111            if self.sort_keys:112                try:113                    mapping = sorted(mapping)114                except TypeError:115                    pass116        for item_key, item_value in mapping:117            node_key = self.represent_data(item_key)118            node_value = self.represent_data(item_value)119            if not (isinstance(node_key, ScalarNode) and not node_key.style):120                best_style = False121            if not (isinstance(node_value, ScalarNode) and not node_value.style):122                best_style = False123            value.append((node_key, node_value))124        if flow_style is None:125            if self.default_flow_style is not None:126                node.flow_style = self.default_flow_style127            else:128                node.flow_style = best_style129        return node130 131    def ignore_aliases(self, data):132        return False133 134class SafeRepresenter(BaseRepresenter):135 136    def ignore_aliases(self, data):137        if data is None:138            return True139        if isinstance(data, tuple) and data == ():140            return True141        if isinstance(data, (str, bytes, bool, int, float)):142            return True143 144    def represent_none(self, data):145        return self.represent_scalar('tag:yaml.org,2002:null', 'null')146 147    def represent_str(self, data):148        return self.represent_scalar('tag:yaml.org,2002:str', data)149 150    def represent_binary(self, data):151        if hasattr(base64, 'encodebytes'):152            data = base64.encodebytes(data).decode('ascii')153        else:154            data = base64.encodestring(data).decode('ascii')155        return self.represent_scalar('tag:yaml.org,2002:binary', data, style='|')156 157    def represent_bool(self, data):158        if data:159            value = 'true'160        else:161            value = 'false'162        return self.represent_scalar('tag:yaml.org,2002:bool', value)163 164    def represent_int(self, data):165        return self.represent_scalar('tag:yaml.org,2002:int', str(data))166 167    inf_value = 1e300168    while repr(inf_value) != repr(inf_value*inf_value):169        inf_value *= inf_value170 171    def represent_float(self, data):172        if data != data or (data == 0.0 and data == 1.0):173            value = '.nan'174        elif data == self.inf_value:175            value = '.inf'176        elif data == -self.inf_value:177            value = '-.inf'178        else:179            value = repr(data).lower()180            # Note that in some cases `repr(data)` represents a float number181            # without the decimal parts.  For instance:182            #   >>> repr(1e17)183            #   '1e17'184            # Unfortunately, this is not a valid float representation according185            # to the definition of the `!!float` tag.  We fix this by adding186            # '.0' before the 'e' symbol.187            if '.' not in value and 'e' in value:188                value = value.replace('e', '.0e', 1)189        return self.represent_scalar('tag:yaml.org,2002:float', value)190 191    def represent_list(self, data):192        #pairs = (len(data) > 0 and isinstance(data, list))193        #if pairs:194        #    for item in data:195        #        if not isinstance(item, tuple) or len(item) != 2:196        #            pairs = False197        #            break198        #if not pairs:199            return self.represent_sequence('tag:yaml.org,2002:seq', data)200        #value = []201        #for item_key, item_value in data:202        #    value.append(self.represent_mapping(u'tag:yaml.org,2002:map',203        #        [(item_key, item_value)]))204        #return SequenceNode(u'tag:yaml.org,2002:pairs', value)205 206    def represent_dict(self, data):207        return self.represent_mapping('tag:yaml.org,2002:map', data)208 209    def represent_set(self, data):210        value = {}211        for key in data:212            value[key] = None213        return self.represent_mapping('tag:yaml.org,2002:set', value)214 215    def represent_date(self, data):216        value = data.isoformat()217        return self.represent_scalar('tag:yaml.org,2002:timestamp', value)218 219    def represent_datetime(self, data):220        value = data.isoformat(' ')221        return self.represent_scalar('tag:yaml.org,2002:timestamp', value)222 223    def represent_yaml_object(self, tag, data, cls, flow_style=None):224        if hasattr(data, '__getstate__'):225            state = data.__getstate__()226        else:227            state = data.__dict__.copy()228        return self.represent_mapping(tag, state, flow_style=flow_style)229 230    def represent_undefined(self, data):231        raise RepresenterError("cannot represent an object", data)232 233SafeRepresenter.add_representer(type(None),234        SafeRepresenter.represent_none)235 236SafeRepresenter.add_representer(str,237        SafeRepresenter.represent_str)238 239SafeRepresenter.add_representer(bytes,240        SafeRepresenter.represent_binary)241 242SafeRepresenter.add_representer(bool,243        SafeRepresenter.represent_bool)244 245SafeRepresenter.add_representer(int,246        SafeRepresenter.represent_int)247 248SafeRepresenter.add_representer(float,249        SafeRepresenter.represent_float)250 251SafeRepresenter.add_representer(list,252        SafeRepresenter.represent_list)253 254SafeRepresenter.add_representer(tuple,255        SafeRepresenter.represent_list)256 257SafeRepresenter.add_representer(dict,258        SafeRepresenter.represent_dict)259 260SafeRepresenter.add_representer(set,261        SafeRepresenter.represent_set)262 263SafeRepresenter.add_representer(datetime.date,264        SafeRepresenter.represent_date)265 266SafeRepresenter.add_representer(datetime.datetime,267        SafeRepresenter.represent_datetime)268 269SafeRepresenter.add_representer(None,270        SafeRepresenter.represent_undefined)271 272class Representer(SafeRepresenter):273 274    def represent_complex(self, data):275        if data.imag == 0.0:276            data = '%r' % data.real277        elif data.real == 0.0:278            data = '%rj' % data.imag279        elif data.imag > 0:280            data = '%r+%rj' % (data.real, data.imag)281        else:282            data = '%r%rj' % (data.real, data.imag)283        return self.represent_scalar('tag:yaml.org,2002:python/complex', data)284 285    def represent_tuple(self, data):286        return self.represent_sequence('tag:yaml.org,2002:python/tuple', data)287 288    def represent_name(self, data):289        name = '%s.%s' % (data.__module__, data.__name__)290        return self.represent_scalar('tag:yaml.org,2002:python/name:'+name, '')291 292    def represent_module(self, data):293        return self.represent_scalar(294                'tag:yaml.org,2002:python/module:'+data.__name__, '')295 296    def represent_object(self, data):297        # We use __reduce__ API to save the data. data.__reduce__ returns298        # a tuple of length 2-5:299        #   (function, args, state, listitems, dictitems)300 301        # For reconstructing, we calls function(*args), then set its state,302        # listitems, and dictitems if they are not None.303 304        # A special case is when function.__name__ == '__newobj__'. In this305        # case we create the object with args[0].__new__(*args).306 307        # Another special case is when __reduce__ returns a string - we don't308        # support it.309 310        # We produce a !!python/object, !!python/object/new or311        # !!python/object/apply node.312 313        cls = type(data)314        if cls in copyreg.dispatch_table:315            reduce = copyreg.dispatch_table[cls](data)316        elif hasattr(data, '__reduce_ex__'):317            reduce = data.__reduce_ex__(2)318        elif hasattr(data, '__reduce__'):319            reduce = data.__reduce__()320        else:321            raise RepresenterError("cannot represent an object", data)322        reduce = (list(reduce)+[None]*5)[:5]323        function, args, state, listitems, dictitems = reduce324        args = list(args)325        if state is None:326            state = {}327        if listitems is not None:328            listitems = list(listitems)329        if dictitems is not None:330            dictitems = dict(dictitems)331        if function.__name__ == '__newobj__':332            function = args[0]333            args = args[1:]334            tag = 'tag:yaml.org,2002:python/object/new:'335            newobj = True336        else:337            tag = 'tag:yaml.org,2002:python/object/apply:'338            newobj = False339        function_name = '%s.%s' % (function.__module__, function.__name__)340        if not args and not listitems and not dictitems \341                and isinstance(state, dict) and newobj:342            return self.represent_mapping(343                    'tag:yaml.org,2002:python/object:'+function_name, state)344        if not listitems and not dictitems  \345                and isinstance(state, dict) and not state:346            return self.represent_sequence(tag+function_name, args)347        value = {}348        if args:349            value['args'] = args350        if state or not isinstance(state, dict):351            value['state'] = state352        if listitems:353            value['listitems'] = listitems354        if dictitems:355            value['dictitems'] = dictitems356        return self.represent_mapping(tag+function_name, value)357 358    def represent_ordered_dict(self, data):359        # Provide uniform representation across different Python versions.360        data_type = type(data)361        tag = 'tag:yaml.org,2002:python/object/apply:%s.%s' \362                % (data_type.__module__, data_type.__name__)363        items = [[key, value] for key, value in data.items()]364        return self.represent_sequence(tag, [items])365 366Representer.add_representer(complex,367        Representer.represent_complex)368 369Representer.add_representer(tuple,370        Representer.represent_tuple)371 372Representer.add_multi_representer(type,373        Representer.represent_name)374 375Representer.add_representer(collections.OrderedDict,376        Representer.represent_ordered_dict)377 378Representer.add_representer(types.FunctionType,379        Representer.represent_name)380 381Representer.add_representer(types.BuiltinFunctionType,382        Representer.represent_name)383 384Representer.add_representer(types.ModuleType,385        Representer.represent_module)386 387Representer.add_multi_representer(object,388        Representer.represent_object)389 390