calibre-web/lib/requests/cookies.py

# -*- coding: utf-8 -*-

"""
Compatibility code to be able to use `cookielib.CookieJar` with requests.

requests.utils imports from here, so be careful with imports.
"""

import time
import collections
from .compat import cookielib, urlparse, urlunparse, Morsel

try:
    import threading
    # grr, pyflakes: this fixes "redefinition of unused 'threading'"
    threading
except ImportError:
    import dummy_threading as threading


class MockRequest(object):
    """Wraps a `requests.Request` to mimic a `urllib2.Request`.

    The code in `cookielib.CookieJar` expects this interface in order to correctly
    manage cookie policies, i.e., determine whether a cookie can be set, given the
    domains of the request and the cookie.

    The original request object is read-only. The client is responsible for collecting
    the new headers via `get_new_headers()` and interpreting them appropriately. You
    probably want `get_cookie_header`, defined below.
    """

    def __init__(self, request):
        self._r = request
        self._new_headers = {}
        self.type = urlparse(self._r.url).scheme

    def get_type(self):
        return self.type

    def get_host(self):
        return urlparse(self._r.url).netloc

    def get_origin_req_host(self):
        return self.get_host()

    def get_full_url(self):
        # Only return the response's URL if the user hadn't set the Host
        # header
        if not self._r.headers.get('Host'):
            return self._r.url
        # If they did set it, retrieve it and reconstruct the expected domain
        host = self._r.headers['Host']
        parsed = urlparse(self._r.url)
        # Reconstruct the URL as we expect it
        return urlunparse([
            parsed.scheme, host, parsed.path, parsed.params, parsed.query,
            parsed.fragment
        ])

    def is_unverifiable(self):
        return True

    def has_header(self, name):
        return name in self._r.headers or name in self._new_headers

    def get_header(self, name, default=None):
        return self._r.headers.get(name, self._new_headers.get(name, default))

    def add_header(self, key, val):
        """cookielib has no legitimate use for this method; add it back if you find one."""
        raise NotImplementedError("Cookie headers should be added with add_unredirected_header()")

    def add_unredirected_header(self, name, value):
        self._new_headers[name] = value

    def get_new_headers(self):
        return self._new_headers

    @property
    def unverifiable(self):
        return self.is_unverifiable()

    @property
    def origin_req_host(self):
        return self.get_origin_req_host()

    @property
    def host(self):
        return self.get_host()


class MockResponse(object):
    """Wraps a `httplib.HTTPMessage` to mimic a `urllib.addinfourl`.

    ...what? Basically, expose the parsed HTTP headers from the server response
    the way `cookielib` expects to see them.
    """

    def __init__(self, headers):
        """Make a MockResponse for `cookielib` to read.

        :param headers: a httplib.HTTPMessage or analogous carrying the headers
        """
        self._headers = headers

    def info(self):
        return self._headers

    def getheaders(self, name):
        self._headers.getheaders(name)


def extract_cookies_to_jar(jar, request, response):
    """Extract the cookies from the response into a CookieJar.

    :param jar: cookielib.CookieJar (not necessarily a RequestsCookieJar)
    :param request: our own requests.Request object
    :param response: urllib3.HTTPResponse object
    """
    if not (hasattr(response, '_original_response') and
            response._original_response):
        return
    # the _original_response field is the wrapped httplib.HTTPResponse object,
    req = MockRequest(request)
    # pull out the HTTPMessage with the headers and put it in the mock:
    res = MockResponse(response._original_response.msg)
    jar.extract_cookies(res, req)


def get_cookie_header(jar, request):
    """Produce an appropriate Cookie header string to be sent with `request`, or None."""
    r = MockRequest(request)
    jar.add_cookie_header(r)
    return r.get_new_headers().get('Cookie')


def remove_cookie_by_name(cookiejar, name, domain=None, path=None):
    """Unsets a cookie by name, by default over all domains and paths.

    Wraps CookieJar.clear(), is O(n).
    """
    clearables = []
    for cookie in cookiejar:
        if cookie.name == name:
            if domain is None or domain == cookie.domain:
                if path is None or path == cookie.path:
                    clearables.append((cookie.domain, cookie.path, cookie.name))

    for domain, path, name in clearables:
        cookiejar.clear(domain, path, name)


class CookieConflictError(RuntimeError):
    """There are two cookies that meet the criteria specified in the cookie jar.
    Use .get and .set and include domain and path args in order to be more specific."""


class RequestsCookieJar(cookielib.CookieJar, collections.MutableMapping):
    """Compatibility class; is a cookielib.CookieJar, but exposes a dict interface.

    This is the CookieJar we create by default for requests and sessions that
    don't specify one, since some clients may expect response.cookies and
    session.cookies to support dict operations.

    Don't use the dict interface internally; it's just for compatibility with
    with external client code. All `requests` code should work out of the box
    with externally provided instances of CookieJar, e.g., LWPCookieJar and
    FileCookieJar.

    Caution: dictionary operations that are normally O(1) may be O(n).

    Unlike a regular CookieJar, this class is pickleable.
    """

    def get(self, name, default=None, domain=None, path=None):
        """Dict-like get() that also supports optional domain and path args in
        order to resolve naming collisions from using one cookie jar over
        multiple domains. Caution: operation is O(n), not O(1)."""
        try:
            return self._find_no_duplicates(name, domain, path)
        except KeyError:
            return default

    def set(self, name, value, **kwargs):
        """Dict-like set() that also supports optional domain and path args in
        order to resolve naming collisions from using one cookie jar over
        multiple domains."""
        # support client code that unsets cookies by assignment of a None value:
        if value is None:
            remove_cookie_by_name(self, name, domain=kwargs.get('domain'), path=kwargs.get('path'))
            return

        if isinstance(value, Morsel):
            c = morsel_to_cookie(value)
        else:
            c = create_cookie(name, value, **kwargs)
        self.set_cookie(c)
        return c

    def iterkeys(self):
        """Dict-like iterkeys() that returns an iterator of names of cookies from the jar.
        See itervalues() and iteritems()."""
        for cookie in iter(self):
            yield cookie.name

    def keys(self):
        """Dict-like keys() that returns a list of names of cookies from the jar.
        See values() and items()."""
        return list(self.iterkeys())

    def itervalues(self):
        """Dict-like itervalues() that returns an iterator of values of cookies from the jar.
        See iterkeys() and iteritems()."""
        for cookie in iter(self):
            yield cookie.value

    def values(self):
        """Dict-like values() that returns a list of values of cookies from the jar.
        See keys() and items()."""
        return list(self.itervalues())

    def iteritems(self):
        """Dict-like iteritems() that returns an iterator of name-value tuples from the jar.
        See iterkeys() and itervalues()."""
        for cookie in iter(self):
            yield cookie.name, cookie.value

    def items(self):
        """Dict-like items() that returns a list of name-value tuples from the jar.
        See keys() and values(). Allows client-code to call "dict(RequestsCookieJar)
        and get a vanilla python dict of key value pairs."""
        return list(self.iteritems())

    def list_domains(self):
        """Utility method to list all the domains in the jar."""
        domains = []
        for cookie in iter(self):
            if cookie.domain not in domains:
                domains.append(cookie.domain)
        return domains

    def list_paths(self):
        """Utility method to list all the paths in the jar."""
        paths = []
        for cookie in iter(self):
            if cookie.path not in paths:
                paths.append(cookie.path)
        return paths

    def multiple_domains(self):
        """Returns True if there are multiple domains in the jar.
        Returns False otherwise."""
        domains = []
        for cookie in iter(self):
            if cookie.domain is not None and cookie.domain in domains:
                return True
            domains.append(cookie.domain)
        return False  # there is only one domain in jar

    def get_dict(self, domain=None, path=None):
        """Takes as an argument an optional domain and path and returns a plain old
        Python dict of name-value pairs of cookies that meet the requirements."""
        dictionary = {}
        for cookie in iter(self):
            if (domain is None or cookie.domain == domain) and (path is None
                                                or cookie.path == path):
                dictionary[cookie.name] = cookie.value
        return dictionary

    def __getitem__(self, name):
        """Dict-like __getitem__() for compatibility with client code. Throws exception
        if there are more than one cookie with name. In that case, use the more
        explicit get() method instead. Caution: operation is O(n), not O(1)."""

        return self._find_no_duplicates(name)

    def __setitem__(self, name, value):
        """Dict-like __setitem__ for compatibility with client code. Throws exception
        if there is already a cookie of that name in the jar. In that case, use the more
        explicit set() method instead."""

        self.set(name, value)

    def __delitem__(self, name):
        """Deletes a cookie given a name. Wraps cookielib.CookieJar's remove_cookie_by_name()."""
        remove_cookie_by_name(self, name)

    def set_cookie(self, cookie, *args, **kwargs):
        if hasattr(cookie.value, 'startswith') and cookie.value.startswith('"') and cookie.value.endswith('"'):
            cookie.value = cookie.value.replace('\\"', '')
        return super(RequestsCookieJar, self).set_cookie(cookie, *args, **kwargs)

    def update(self, other):
        """Updates this jar with cookies from another CookieJar or dict-like"""
        if isinstance(other, cookielib.CookieJar):
            for cookie in other:
                self.set_cookie(cookie)
        else:
            super(RequestsCookieJar, self).update(other)

    def _find(self, name, domain=None, path=None):
        """Requests uses this method internally to get cookie values. Takes as args name
        and optional domain and path. Returns a cookie.value. If there are conflicting cookies,
        _find arbitrarily chooses one. See _find_no_duplicates if you want an exception thrown
        if there are conflicting cookies."""
        for cookie in iter(self):
            if cookie.name == name:
                if domain is None or cookie.domain == domain:
                    if path is None or cookie.path == path:
                        return cookie.value

        raise KeyError('name=%r, domain=%r, path=%r' % (name, domain, path))

    def _find_no_duplicates(self, name, domain=None, path=None):
        """__get_item__ and get call _find_no_duplicates -- never used in Requests internally.
        Takes as args name and optional domain and path. Returns a cookie.value.
        Throws KeyError if cookie is not found and CookieConflictError if there are
        multiple cookies that match name and optionally domain and path."""
        toReturn = None
        for cookie in iter(self):
            if cookie.name == name:
                if domain is None or cookie.domain == domain:
                    if path is None or cookie.path == path:
                        if toReturn is not None:  # if there are multiple cookies that meet passed in criteria
                            raise CookieConflictError('There are multiple cookies with name, %r' % (name))
                        toReturn = cookie.value  # we will eventually return this as long as no cookie conflict

        if toReturn:
            return toReturn
        raise KeyError('name=%r, domain=%r, path=%r' % (name, domain, path))

    def __getstate__(self):
        """Unlike a normal CookieJar, this class is pickleable."""
        state = self.__dict__.copy()
        # remove the unpickleable RLock object
        state.pop('_cookies_lock')
        return state

    def __setstate__(self, state):
        """Unlike a normal CookieJar, this class is pickleable."""
        self.__dict__.update(state)
        if '_cookies_lock' not in self.__dict__:
            self._cookies_lock = threading.RLock()

    def copy(self):
        """Return a copy of this RequestsCookieJar."""
        new_cj = RequestsCookieJar()
        new_cj.update(self)
        return new_cj


def create_cookie(name, value, **kwargs):
    """Make a cookie from underspecified parameters.

    By default, the pair of `name` and `value` will be set for the domain ''
    and sent on every request (this is sometimes called a "supercookie").
    """
    result = dict(
        version=0,
        name=name,
        value=value,
        port=None,
        domain='',
        path='/',
        secure=False,
        expires=None,
        discard=True,
        comment=None,
        comment_url=None,
        rest={'HttpOnly': None},
        rfc2109=False,)

    badargs = set(kwargs) - set(result)
    if badargs:
        err = 'create_cookie() got unexpected keyword arguments: %s'
        raise TypeError(err % list(badargs))

    result.update(kwargs)
    result['port_specified'] = bool(result['port'])
    result['domain_specified'] = bool(result['domain'])
    result['domain_initial_dot'] = result['domain'].startswith('.')
    result['path_specified'] = bool(result['path'])

    return cookielib.Cookie(**result)


def morsel_to_cookie(morsel):
    """Convert a Morsel object into a Cookie containing the one k/v pair."""

    expires = None
    if morsel['max-age']:
        expires = time.time() + morsel['max-age']
    elif morsel['expires']:
        time_template = '%a, %d-%b-%Y %H:%M:%S GMT'
        expires = time.mktime(
            time.strptime(morsel['expires'], time_template)) - time.timezone
    return create_cookie(
        comment=morsel['comment'],
        comment_url=bool(morsel['comment']),
        discard=False,
        domain=morsel['domain'],
        expires=expires,
        name=morsel.key,
        path=morsel['path'],
        port=None,
        rest={'HttpOnly': morsel['httponly']},
        rfc2109=False,
        secure=bool(morsel['secure']),
        value=morsel.value,
        version=morsel['version'] or 0,
    )


def cookiejar_from_dict(cookie_dict, cookiejar=None, overwrite=True):
    """Returns a CookieJar from a key/value dictionary.

    :param cookie_dict: Dict of key/values to insert into CookieJar.
    :param cookiejar: (optional) A cookiejar to add the cookies to.
    :param overwrite: (optional) If False, will not replace cookies
        already in the jar with new ones.
    """
    if cookiejar is None:
        cookiejar = RequestsCookieJar()

    if cookie_dict is not None:
        names_from_jar = [cookie.name for cookie in cookiejar]
        for name in cookie_dict:
            if overwrite or (name not in names_from_jar):
                cookiejar.set_cookie(create_cookie(name, cookie_dict[name]))

    return cookiejar


def merge_cookies(cookiejar, cookies):
    """Add cookies to cookiejar and returns a merged CookieJar.

    :param cookiejar: CookieJar object to add the cookies to.
    :param cookies: Dictionary or CookieJar object to be added.
    """
    if not isinstance(cookiejar, cookielib.CookieJar):
        raise ValueError('You can only merge into CookieJar')
    
    if isinstance(cookies, dict):
        cookiejar = cookiejar_from_dict(
            cookies, cookiejar=cookiejar, overwrite=False)
    elif isinstance(cookies, cookielib.CookieJar):
        try:
            cookiejar.update(cookies)
        except AttributeError:
            for cookie_in_jar in cookies:
                cookiejar.set_cookie(cookie_in_jar)

    return cookiejar