Source

pyyaml / lib3 / yaml / __init__.py

Kirill Simonov 197fb99 









Kirill Simonov e44368b 






Kirill Simonov 197fb99 
























































































Kirill Simonov 8c1d3a1 
Kirill Simonov 197fb99 






Kirill Simonov 8c1d3a1 



Kirill Simonov 197fb99 






















Kirill Simonov 8c1d3a1 
Kirill Simonov 197fb99 






Kirill Simonov 8c1d3a1 



Kirill Simonov 197fb99 



































































































































from .error import *

from .tokens import *
from .events import *
from .nodes import *

from .loader import *
from .dumper import *

__version__ = '3.08'
try:
    from .cyaml import *
    __with_libyaml__ = True
except ImportError:
    __with_libyaml__ = False

import io

def scan(stream, Loader=Loader):
    """
    Scan a YAML stream and produce scanning tokens.
    """
    loader = Loader(stream)
    while loader.check_token():
        yield loader.get_token()

def parse(stream, Loader=Loader):
    """
    Parse a YAML stream and produce parsing events.
    """
    loader = Loader(stream)
    while loader.check_event():
        yield loader.get_event()

def compose(stream, Loader=Loader):
    """
    Parse the first YAML document in a stream
    and produce the corresponding representation tree.
    """
    loader = Loader(stream)
    return loader.get_single_node()

def compose_all(stream, Loader=Loader):
    """
    Parse all YAML documents in a stream
    and produce corresponsing representation trees.
    """
    loader = Loader(stream)
    while loader.check_node():
        yield loader.get_node()

def load(stream, Loader=Loader):
    """
    Parse the first YAML document in a stream
    and produce the corresponding Python object.
    """
    loader = Loader(stream)
    return loader.get_single_data()

def load_all(stream, Loader=Loader):
    """
    Parse all YAML documents in a stream
    and produce corresponding Python objects.
    """
    loader = Loader(stream)
    while loader.check_data():
        yield loader.get_data()

def safe_load(stream):
    """
    Parse the first YAML document in a stream
    and produce the corresponding Python object.
    Resolve only basic YAML tags.
    """
    return load(stream, SafeLoader)

def safe_load_all(stream):
    """
    Parse all YAML documents in a stream
    and produce corresponding Python objects.
    Resolve only basic YAML tags.
    """
    return load_all(stream, SafeLoader)

def emit(events, stream=None, Dumper=Dumper,
        canonical=None, indent=None, width=None,
        allow_unicode=None, line_break=None):
    """
    Emit YAML parsing events into a stream.
    If stream is None, return the produced string instead.
    """
    getvalue = None
    if stream is None:
        stream = io.StringIO()
        getvalue = stream.getvalue
    dumper = Dumper(stream, canonical=canonical, indent=indent, width=width,
            allow_unicode=allow_unicode, line_break=line_break)
    for event in events:
        dumper.emit(event)
    if getvalue:
        return getvalue()

def serialize_all(nodes, stream=None, Dumper=Dumper,
        canonical=None, indent=None, width=None,
        allow_unicode=None, line_break=None,
        encoding=None, explicit_start=None, explicit_end=None,
        version=None, tags=None):
    """
    Serialize a sequence of representation trees into a YAML stream.
    If stream is None, return the produced string instead.
    """
    getvalue = None
    if stream is None:
        if encoding is None:
            stream = io.StringIO()
        else:
            stream = io.BytesIO()
        getvalue = stream.getvalue
    dumper = Dumper(stream, canonical=canonical, indent=indent, width=width,
            allow_unicode=allow_unicode, line_break=line_break,
            encoding=encoding, version=version, tags=tags,
            explicit_start=explicit_start, explicit_end=explicit_end)
    dumper.open()
    for node in nodes:
        dumper.serialize(node)
    dumper.close()
    if getvalue:
        return getvalue()

def serialize(node, stream=None, Dumper=Dumper, **kwds):
    """
    Serialize a representation tree into a YAML stream.
    If stream is None, return the produced string instead.
    """
    return serialize_all([node], stream, Dumper=Dumper, **kwds)

def dump_all(documents, stream=None, Dumper=Dumper,
        default_style=None, default_flow_style=None,
        canonical=None, indent=None, width=None,
        allow_unicode=None, line_break=None,
        encoding=None, explicit_start=None, explicit_end=None,
        version=None, tags=None):
    """
    Serialize a sequence of Python objects into a YAML stream.
    If stream is None, return the produced string instead.
    """
    getvalue = None
    if stream is None:
        if encoding is None:
            stream = io.StringIO()
        else:
            stream = io.BytesIO()
        getvalue = stream.getvalue
    dumper = Dumper(stream, default_style=default_style,
            default_flow_style=default_flow_style,
            canonical=canonical, indent=indent, width=width,
            allow_unicode=allow_unicode, line_break=line_break,
            encoding=encoding, version=version, tags=tags,
            explicit_start=explicit_start, explicit_end=explicit_end)
    dumper.open()
    for data in documents:
        dumper.represent(data)
    dumper.close()
    if getvalue:
        return getvalue()

def dump(data, stream=None, Dumper=Dumper, **kwds):
    """
    Serialize a Python object into a YAML stream.
    If stream is None, return the produced string instead.
    """
    return dump_all([data], stream, Dumper=Dumper, **kwds)

def safe_dump_all(documents, stream=None, **kwds):
    """
    Serialize a sequence of Python objects into a YAML stream.
    Produce only basic YAML tags.
    If stream is None, return the produced string instead.
    """
    return dump_all(documents, stream, Dumper=SafeDumper, **kwds)

def safe_dump(data, stream=None, **kwds):
    """
    Serialize a Python object into a YAML stream.
    Produce only basic YAML tags.
    If stream is None, return the produced string instead.
    """
    return dump_all([data], stream, Dumper=SafeDumper, **kwds)

def add_implicit_resolver(tag, regexp, first=None,
        Loader=Loader, Dumper=Dumper):
    """
    Add an implicit scalar detector.
    If an implicit scalar value matches the given regexp,
    the corresponding tag is assigned to the scalar.
    first is a sequence of possible initial characters or None.
    """
    Loader.add_implicit_resolver(tag, regexp, first)
    Dumper.add_implicit_resolver(tag, regexp, first)

def add_path_resolver(tag, path, kind=None, Loader=Loader, Dumper=Dumper):
    """
    Add a path based resolver for the given tag.
    A path is a list of keys that forms a path
    to a node in the representation tree.
    Keys can be string values, integers, or None.
    """
    Loader.add_path_resolver(tag, path, kind)
    Dumper.add_path_resolver(tag, path, kind)

def add_constructor(tag, constructor, Loader=Loader):
    """
    Add a constructor for the given tag.
    Constructor is a function that accepts a Loader instance
    and a node object and produces the corresponding Python object.
    """
    Loader.add_constructor(tag, constructor)

def add_multi_constructor(tag_prefix, multi_constructor, Loader=Loader):
    """
    Add a multi-constructor for the given tag prefix.
    Multi-constructor is called for a node if its tag starts with tag_prefix.
    Multi-constructor accepts a Loader instance, a tag suffix,
    and a node object and produces the corresponding Python object.
    """
    Loader.add_multi_constructor(tag_prefix, multi_constructor)

def add_representer(data_type, representer, Dumper=Dumper):
    """
    Add a representer for the given type.
    Representer is a function accepting a Dumper instance
    and an instance of the given data type
    and producing the corresponding representation node.
    """
    Dumper.add_representer(data_type, representer)

def add_multi_representer(data_type, multi_representer, Dumper=Dumper):
    """
    Add a representer for the given type.
    Multi-representer is a function accepting a Dumper instance
    and an instance of the given data type or subtype
    and producing the corresponding representation node.
    """
    Dumper.add_multi_representer(data_type, multi_representer)

class YAMLObjectMetaclass(type):
    """
    The metaclass for YAMLObject.
    """
    def __init__(cls, name, bases, kwds):
        super(YAMLObjectMetaclass, cls).__init__(name, bases, kwds)
        if 'yaml_tag' in kwds and kwds['yaml_tag'] is not None:
            cls.yaml_loader.add_constructor(cls.yaml_tag, cls.from_yaml)
            cls.yaml_dumper.add_representer(cls, cls.to_yaml)

class YAMLObject(metaclass=YAMLObjectMetaclass):
    """
    An object that can dump itself to a YAML stream
    and load itself from a YAML stream.
    """

    __slots__ = ()  # no direct instantiation, so allow immutable subclasses

    yaml_loader = Loader
    yaml_dumper = Dumper

    yaml_tag = None
    yaml_flow_style = None

    @classmethod
    def from_yaml(cls, loader, node):
        """
        Convert a representation node to a Python object.
        """
        return loader.construct_yaml_object(node, cls)

    @classmethod
    def to_yaml(cls, dumper, data):
        """
        Convert a Python object to a representation node.
        """
        return dumper.represent_yaml_object(cls.yaml_tag, data, cls,
                flow_style=cls.yaml_flow_style)