"""Response classes used by urllib.
The base class, addbase, defines a minimal file-like interface,
including read() and readline(). The typical response object is an
addinfourl instance, which defines an info() method that returns
headers and a geturl() method that returns the url.
"""
class addbase(object):
"""Base class for addinfo and addclosehook."""
# XXX Add a method to expose the timeout on the underlying socket?
def __init__(self, fp):
# TODO(jhylton): Is there a better way to delegate using io?
self.fp = fp
self.read = self.fp.read
self.readline = self.fp.readline
# TODO(jhylton): Make sure an object with readlines() is also iterable
if hasattr(self.fp, "readlines"):
self.readlines = self.fp.readlines
if hasattr(self.fp, "fileno"):
self.fileno = self.fp.fileno
else:
self.fileno = lambda: None
def __iter__(self):
# Assigning `__iter__` to the instance doesn't work as intended
# because the iter builtin does something like `cls.__iter__(obj)`
# and thus fails to find the _bound_ method `obj.__iter__`.
# Returning just `self.fp` works for built-in file objects but
# might not work for general file-like objects.
return iter(self.fp)
def __repr__(self):
return '<%s at %r whose fp = %r>' % (self.__class__.__name__,
id(self), self.fp)
def close(self):
if self.fp:
self.fp.close()
self.fp = None
self.read = None
self.readline = None
self.readlines = None
self.fileno = None
self.__iter__ = None
self.__next__ = None
def __enter__(self):
if self.fp is None:
raise ValueError("I/O operation on closed file")
return self
def __exit__(self, type, value, traceback):
self.close()
class addclosehook(addbase):
"""Class to add a close hook to an open file."""
def __init__(self, fp, closehook, *hookargs):
addbase.__init__(self, fp)
self.closehook = closehook
self.hookargs = hookargs
def close(self):
if self.closehook:
self.closehook(*self.hookargs)
self.closehook = None
self.hookargs = None
addbase.close(self)
class addinfo(addbase):
"""class to add an info() method to an open file."""
def __init__(self, fp, headers):
addbase.__init__(self, fp)
self.headers = headers
def info(self):
return self.headers
class addinfourl(addbase):
"""class to add info() and geturl() methods to an open file."""
def __init__(self, fp, headers, url, code=None):
addbase.__init__(self, fp)
self.headers = headers
self.url = url
self.code = code
def info(self):
return self.headers
def getcode(self):
return self.code
def geturl(self):
return self.url
