Merge branch 'master' into dan_stateless

1 files changed, 184 insertions, 0 deletions

diff --git a/src/console/zmq/eventloop/minitornado/util.py b/src/console/zmq/eventloop/minitornado/util.py
new file mode 100755
index 00000000..c1e2eb95
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+++ b/src/console/zmq/eventloop/minitornado/util.py
@@ -0,0 +1,184 @@
+"""Miscellaneous utility functions and classes.
+
+This module is used internally by Tornado.  It is not necessarily expected
+that the functions and classes defined here will be useful to other
+applications, but they are documented here in case they are.
+
+The one public-facing part of this module is the `Configurable` class
+and its `~Configurable.configure` method, which becomes a part of the
+interface of its subclasses, including `.AsyncHTTPClient`, `.IOLoop`,
+and `.Resolver`.
+"""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+import sys
+
+
+def import_object(name):
+    """Imports an object by name.
+
+    import_object('x') is equivalent to 'import x'.
+    import_object('x.y.z') is equivalent to 'from x.y import z'.
+
+    >>> import tornado.escape
+    >>> import_object('tornado.escape') is tornado.escape
+    True
+    >>> import_object('tornado.escape.utf8') is tornado.escape.utf8
+    True
+    >>> import_object('tornado') is tornado
+    True
+    >>> import_object('tornado.missing_module')
+    Traceback (most recent call last):
+        ...
+    ImportError: No module named missing_module
+    """
+    if name.count('.') == 0:
+        return __import__(name, None, None)
+
+    parts = name.split('.')
+    obj = __import__('.'.join(parts[:-1]), None, None, [parts[-1]], 0)
+    try:
+        return getattr(obj, parts[-1])
+    except AttributeError:
+        raise ImportError("No module named %s" % parts[-1])
+
+
+# Fake unicode literal support:  Python 3.2 doesn't have the u'' marker for
+# literal strings, and alternative solutions like "from __future__ import
+# unicode_literals" have other problems (see PEP 414).  u() can be applied
+# to ascii strings that include \u escapes (but they must not contain
+# literal non-ascii characters).
+if type('') is not type(b''):
+    def u(s):
+        return s
+    bytes_type = bytes
+    unicode_type = str
+    basestring_type = str
+else:
+    def u(s):
+        return s.decode('unicode_escape')
+    bytes_type = str
+    unicode_type = unicode
+    basestring_type = basestring
+
+
+if sys.version_info > (3,):
+    exec("""
+def raise_exc_info(exc_info):
+    raise exc_info[1].with_traceback(exc_info[2])
+
+def exec_in(code, glob, loc=None):
+    if isinstance(code, str):
+        code = compile(code, '<string>', 'exec', dont_inherit=True)
+    exec(code, glob, loc)
+""")
+else:
+    exec("""
+def raise_exc_info(exc_info):
+    raise exc_info[0], exc_info[1], exc_info[2]
+
+def exec_in(code, glob, loc=None):
+    if isinstance(code, basestring):
+        # exec(string) inherits the caller's future imports; compile
+        # the string first to prevent that.
+        code = compile(code, '<string>', 'exec', dont_inherit=True)
+    exec code in glob, loc
+""")
+
+
+class Configurable(object):
+    """Base class for configurable interfaces.
+
+    A configurable interface is an (abstract) class whose constructor
+    acts as a factory function for one of its implementation subclasses.
+    The implementation subclass as well as optional keyword arguments to
+    its initializer can be set globally at runtime with `configure`.
+
+    By using the constructor as the factory method, the interface
+    looks like a normal class, `isinstance` works as usual, etc.  This
+    pattern is most useful when the choice of implementation is likely
+    to be a global decision (e.g. when `~select.epoll` is available,
+    always use it instead of `~select.select`), or when a
+    previously-monolithic class has been split into specialized
+    subclasses.
+
+    Configurable subclasses must define the class methods
+    `configurable_base` and `configurable_default`, and use the instance
+    method `initialize` instead of ``__init__``.
+    """
+    __impl_class = None
+    __impl_kwargs = None
+
+    def __new__(cls, **kwargs):
+        base = cls.configurable_base()
+        args = {}
+        if cls is base:
+            impl = cls.configured_class()
+            if base.__impl_kwargs:
+                args.update(base.__impl_kwargs)
+        else:
+            impl = cls
+        args.update(kwargs)
+        instance = super(Configurable, cls).__new__(impl)
+        # initialize vs __init__ chosen for compatiblity with AsyncHTTPClient
+        # singleton magic.  If we get rid of that we can switch to __init__
+        # here too.
+        instance.initialize(**args)
+        return instance
+
+    @classmethod
+    def configurable_base(cls):
+        """Returns the base class of a configurable hierarchy.
+
+        This will normally return the class in which it is defined.
+        (which is *not* necessarily the same as the cls classmethod parameter).
+        """
+        raise NotImplementedError()
+
+    @classmethod
+    def configurable_default(cls):
+        """Returns the implementation class to be used if none is configured."""
+        raise NotImplementedError()
+
+    def initialize(self):
+        """Initialize a `Configurable` subclass instance.
+
+        Configurable classes should use `initialize` instead of ``__init__``.
+        """
+
+    @classmethod
+    def configure(cls, impl, **kwargs):
+        """Sets the class to use when the base class is instantiated.
+
+        Keyword arguments will be saved and added to the arguments passed
+        to the constructor.  This can be used to set global defaults for
+        some parameters.
+        """
+        base = cls.configurable_base()
+        if isinstance(impl, (unicode_type, bytes_type)):
+            impl = import_object(impl)
+        if impl is not None and not issubclass(impl, cls):
+            raise ValueError("Invalid subclass of %s" % cls)
+        base.__impl_class = impl
+        base.__impl_kwargs = kwargs
+
+    @classmethod
+    def configured_class(cls):
+        """Returns the currently configured class."""
+        base = cls.configurable_base()
+        if cls.__impl_class is None:
+            base.__impl_class = cls.configurable_default()
+        return base.__impl_class
+
+    @classmethod
+    def _save_configuration(cls):
+        base = cls.configurable_base()
+        return (base.__impl_class, base.__impl_kwargs)
+
+    @classmethod
+    def _restore_configuration(cls, saved):
+        base = cls.configurable_base()
+        base.__impl_class = saved[0]
+        base.__impl_kwargs = saved[1]
+