diff --git a/oauth2/__init__.py b/oauth2/__init__.py
index 835270e3..71430342 100644
--- a/oauth2/__init__.py
+++ b/oauth2/__init__.py
@@ -49,812 +49,23 @@
 
 __version__ = _version.__version__
 
-OAUTH_VERSION = '1.0'  # Hi Blaine!
-HTTP_METHOD = 'GET'
-SIGNATURE_METHOD = 'PLAINTEXT'
 
-
-class Error(RuntimeError):
-    """Generic exception class."""
-
-    def __init__(self, message='OAuth error occurred.'):
-        self._message = message
-
-    @property
-    def message(self):
-        """A hack to get around the deprecation errors in 2.6."""
-        return self._message
-
-    def __str__(self):
-        return self._message
-
-
-class MissingSignature(Error):
-    pass
-
-
-def build_authenticate_header(realm=''):
-    """Optional WWW-Authenticate header (401 error)"""
-    return {'WWW-Authenticate': 'OAuth realm="%s"' % realm}
-
-
-def build_xoauth_string(url, consumer, token=None):
-    """Build an XOAUTH string for use in SMTP/IMPA authentication."""
-    request = Request.from_consumer_and_token(consumer, token,
-        "GET", url)
-
-    signing_method = SignatureMethod_HMAC_SHA1()
-    request.sign_request(signing_method, consumer, token)
-
-    params = []
-    for k, v in sorted(request.iteritems()):
-        if v is not None:
-            params.append('%s="%s"' % (k, escape(v)))
-
-    return "%s %s %s" % ("GET", url, ','.join(params))
-
-
-def to_unicode(s):
-    """ Convert to unicode, raise exception with instructive error
-    message if s is not unicode, ascii, or utf-8. """
-    if not isinstance(s, unicode):
-        if not isinstance(s, str):
-            raise TypeError('You are required to pass either unicode or string here, not: %r (%s)' % (type(s), s))
-        try:
-            s = s.decode('utf-8')
-        except UnicodeDecodeError, le:
-            raise TypeError('You are required to pass either a unicode object or a utf-8 string here. You passed a Python string object which contained non-utf-8: %r. The UnicodeDecodeError that resulted from attempting to interpret it as utf-8 was: %s' % (s, le,))
-    return s
-
-def to_utf8(s):
-    return to_unicode(s).encode('utf-8')
-
-def to_unicode_if_string(s):
-    if isinstance(s, basestring):
-        return to_unicode(s)
-    else:
-        return s
-
-def to_utf8_if_string(s):
-    if isinstance(s, basestring):
-        return to_utf8(s)
-    else:
-        return s
-
-def to_unicode_optional_iterator(x):
-    """
-    Raise TypeError if x is a str containing non-utf8 bytes or if x is
-    an iterable which contains such a str.
-    """
-    if isinstance(x, basestring):
-        return to_unicode(x)
-
-    try:
-        l = list(x)
-    except TypeError, e:
-        assert 'is not iterable' in str(e)
-        return x
-    else:
-        return [ to_unicode(e) for e in l ]
-
-def to_utf8_optional_iterator(x):
-    """
-    Raise TypeError if x is a str or if x is an iterable which
-    contains a str.
-    """
-    if isinstance(x, basestring):
-        return to_utf8(x)
-
-    try:
-        l = list(x)
-    except TypeError, e:
-        assert 'is not iterable' in str(e)
-        return x
-    else:
-        return [ to_utf8_if_string(e) for e in l ]
-
-def escape(s):
-    """Escape a URL including any /."""
-    return urllib.quote(s.encode('utf-8'), safe='~')
-
-def generate_timestamp():
-    """Get seconds since epoch (UTC)."""
-    return int(time.time())
-
-
-def generate_nonce(length=8):
-    """Generate pseudorandom number."""
-    return ''.join([str(random.randint(0, 9)) for i in range(length)])
-
-
-def generate_verifier(length=8):
-    """Generate pseudorandom number."""
-    return ''.join([str(random.randint(0, 9)) for i in range(length)])
-
-
-class Consumer(object):
-    """A consumer of OAuth-protected services.
- 
-    The OAuth consumer is a "third-party" service that wants to access
-    protected resources from an OAuth service provider on behalf of an end
-    user. It's kind of the OAuth client.
- 
-    Usually a consumer must be registered with the service provider by the
-    developer of the consumer software. As part of that process, the service
-    provider gives the consumer a *key* and a *secret* with which the consumer
-    software can identify itself to the service. The consumer will include its
-    key in each request to identify itself, but will use its secret only when
-    signing requests, to prove that the request is from that particular
-    registered consumer.
- 
-    Once registered, the consumer can then use its consumer credentials to ask
-    the service provider for a request token, kicking off the OAuth
-    authorization process.
-    """
-
-    key = None
-    secret = None
-
-    def __init__(self, key, secret):
-        self.key = key
-        self.secret = secret
-
-        if self.key is None or self.secret is None:
-            raise ValueError("Key and secret must be set.")
-
-    def __str__(self):
-        data = {'oauth_consumer_key': self.key,
-            'oauth_consumer_secret': self.secret}
-
-        return urllib.urlencode(data)
-
-
-class Token(object):
-    """An OAuth credential used to request authorization or a protected
-    resource.
- 
-    Tokens in OAuth comprise a *key* and a *secret*. The key is included in
-    requests to identify the token being used, but the secret is used only in
-    the signature, to prove that the requester is who the server gave the
-    token to.
- 
-    When first negotiating the authorization, the consumer asks for a *request
-    token* that the live user authorizes with the service provider. The
-    consumer then exchanges the request token for an *access token* that can
-    be used to access protected resources.
-    """
-
-    key = None
-    secret = None
-    callback = None
-    callback_confirmed = None
-    verifier = None
-
-    def __init__(self, key, secret):
-        self.key = key
-        self.secret = secret
-
-        if self.key is None or self.secret is None:
-            raise ValueError("Key and secret must be set.")
-
-    def set_callback(self, callback):
-        self.callback = callback
-        self.callback_confirmed = 'true'
-
-    def set_verifier(self, verifier=None):
-        if verifier is not None:
-            self.verifier = verifier
-        else:
-            self.verifier = generate_verifier()
-
-    def get_callback_url(self):
-        if self.callback and self.verifier:
-            # Append the oauth_verifier.
-            parts = urlparse.urlparse(self.callback)
-            scheme, netloc, path, params, query, fragment = parts[:6]
-            if query:
-                query = '%s&oauth_verifier=%s' % (query, self.verifier)
-            else:
-                query = 'oauth_verifier=%s' % self.verifier
-            return urlparse.urlunparse((scheme, netloc, path, params,
-                query, fragment))
-        return self.callback
-
-    def to_string(self):
-        """Returns this token as a plain string, suitable for storage.
- 
-        The resulting string includes the token's secret, so you should never
-        send or store this string where a third party can read it.
-        """
-
-        data = {
-            'oauth_token': self.key,
-            'oauth_token_secret': self.secret,
-        }
-
-        if self.callback_confirmed is not None:
-            data['oauth_callback_confirmed'] = self.callback_confirmed
-        return urllib.urlencode(data)
- 
-    @staticmethod
-    def from_string(s):
-        """Deserializes a token from a string like one returned by
-        `to_string()`."""
-
-        if not len(s):
-            raise ValueError("Invalid parameter string.")
-
-        params = parse_qs(s, keep_blank_values=False)
-        if not len(params):
-            raise ValueError("Invalid parameter string.")
-
-        try:
-            key = params['oauth_token'][0]
-        except Exception:
-            raise ValueError("'oauth_token' not found in OAuth request.")
-
-        try:
-            secret = params['oauth_token_secret'][0]
-        except Exception:
-            raise ValueError("'oauth_token_secret' not found in " 
-                "OAuth request.")
-
-        token = Token(key, secret)
-        try:
-            token.callback_confirmed = params['oauth_callback_confirmed'][0]
-        except KeyError:
-            pass  # 1.0, no callback confirmed.
-        return token
-
-    def __str__(self):
-        return self.to_string()
-
-
-def setter(attr):
-    name = attr.__name__
- 
-    def getter(self):
-        try:
-            return self.__dict__[name]
-        except KeyError:
-            raise AttributeError(name)
- 
-    def deleter(self):
-        del self.__dict__[name]
- 
-    return property(getter, attr, deleter)
-
-
-class Request(dict):
- 
-    """The parameters and information for an HTTP request, suitable for
-    authorizing with OAuth credentials.
- 
-    When a consumer wants to access a service's protected resources, it does
-    so using a signed HTTP request identifying itself (the consumer) with its
-    key, and providing an access token authorized by the end user to access
-    those resources.
- 
-    """
- 
-    version = OAUTH_VERSION
-
-    def __init__(self, method=HTTP_METHOD, url=None, parameters=None,
-                 body='', is_form_encoded=False):
-        if url is not None:
-            self.url = to_unicode(url)
-        self.method = method
-        if parameters is not None:
-            for k, v in parameters.iteritems():
-                k = to_unicode(k)
-                v = to_unicode_optional_iterator(v)
-                self[k] = v
-        self.body = body
-        self.is_form_encoded = is_form_encoded
-
-
-    @setter
-    def url(self, value):
-        self.__dict__['url'] = value
-        if value is not None:
-            scheme, netloc, path, params, query, fragment = urlparse.urlparse(value)
-
-            # Exclude default port numbers.
-            if scheme == 'http' and netloc[-3:] == ':80':
-                netloc = netloc[:-3]
-            elif scheme == 'https' and netloc[-4:] == ':443':
-                netloc = netloc[:-4]
-            if scheme not in ('http', 'https'):
-                raise ValueError("Unsupported URL %s (%s)." % (value, scheme))
-
-            # Normalized URL excludes params, query, and fragment.
-            self.normalized_url = urlparse.urlunparse((scheme, netloc, path, None, None, None))
-        else:
-            self.normalized_url = None
-            self.__dict__['url'] = None
- 
-    @setter
-    def method(self, value):
-        self.__dict__['method'] = value.upper()
- 
-    def _get_timestamp_nonce(self):
-        return self['oauth_timestamp'], self['oauth_nonce']
- 
-    def get_nonoauth_parameters(self):
-        """Get any non-OAuth parameters."""
-        return dict([(k, v) for k, v in self.iteritems() 
-                    if not k.startswith('oauth_')])
- 
-    def to_header(self, realm=''):
-        """Serialize as a header for an HTTPAuth request."""
-        oauth_params = ((k, v) for k, v in self.items() 
-                            if k.startswith('oauth_'))
-        stringy_params = ((k, escape(str(v))) for k, v in oauth_params)
-        header_params = ('%s="%s"' % (k, v) for k, v in stringy_params)
-        params_header = ', '.join(header_params)
- 
-        auth_header = 'OAuth realm="%s"' % realm
-        if params_header:
-            auth_header = "%s, %s" % (auth_header, params_header)
- 
-        return {'Authorization': auth_header}
- 
-    def to_postdata(self):
-        """Serialize as post data for a POST request."""
-        d = {}
-        for k, v in self.iteritems():
-            d[k.encode('utf-8')] = to_utf8_optional_iterator(v)
-
-        # tell urlencode to deal with sequence values and map them correctly
-        # to resulting querystring. for example self["k"] = ["v1", "v2"] will
-        # result in 'k=v1&k=v2' and not k=%5B%27v1%27%2C+%27v2%27%5D
-        return urllib.urlencode(d, True).replace('+', '%20')
- 
-    def to_url(self):
-        """Serialize as a URL for a GET request."""
-        base_url = urlparse.urlparse(self.url)
-        try:
-            query = base_url.query
-        except AttributeError:
-            # must be python <2.5
-            query = base_url[4]
-        query = parse_qs(query)
-        for k, v in self.items():
-            query.setdefault(k, []).append(v)
-        
-        try:
-            scheme = base_url.scheme
-            netloc = base_url.netloc
-            path = base_url.path
-            params = base_url.params
-            fragment = base_url.fragment
-        except AttributeError:
-            # must be python <2.5
-            scheme = base_url[0]
-            netloc = base_url[1]
-            path = base_url[2]
-            params = base_url[3]
-            fragment = base_url[5]
-        
-        url = (scheme, netloc, path, params,
-               urllib.urlencode(query, True), fragment)
-        return urlparse.urlunparse(url)
-
-    def get_parameter(self, parameter):
-        ret = self.get(parameter)
-        if ret is None:
-            raise Error('Parameter not found: %s' % parameter)
-
-        return ret
-
-    def get_normalized_parameters(self):
-        """Return a string that contains the parameters that must be signed."""
-        items = []
-        for key, value in self.iteritems():
-            if key == 'oauth_signature':
-                continue
-            # 1.0a/9.1.1 states that kvp must be sorted by key, then by value,
-            # so we unpack sequence values into multiple items for sorting.
-            if isinstance(value, basestring):
-                items.append((to_utf8_if_string(key), to_utf8(value)))
-            else:
-                try:
-                    value = list(value)
-                except TypeError, e:
-                    assert 'is not iterable' in str(e)
-                    items.append((to_utf8_if_string(key), to_utf8_if_string(value)))
-                else:
-                    items.extend((to_utf8_if_string(key), to_utf8_if_string(item)) for item in value)
-
-        # Include any query string parameters from the provided URL
-        query = urlparse.urlparse(self.url)[4]
-
-        url_items = self._split_url_string(query).items()
-        url_items = [(to_utf8(k), to_utf8(v)) for k, v in url_items if k != 'oauth_signature' ]
-        items.extend(url_items)
-
-        items.sort()
-        encoded_str = urllib.urlencode(items)
-        # Encode signature parameters per Oauth Core 1.0 protocol
-        # spec draft 7, section 3.6
-        # (http://tools.ietf.org/html/draft-hammer-oauth-07#section-3.6)
-        # Spaces must be encoded with "%20" instead of "+"
-        return encoded_str.replace('+', '%20').replace('%7E', '~')
-
-    def sign_request(self, signature_method, consumer, token):
-        """Set the signature parameter to the result of sign."""
-
-        if not self.is_form_encoded:
-            # according to
-            # http://oauth.googlecode.com/svn/spec/ext/body_hash/1.0/oauth-bodyhash.html
-            # section 4.1.1 "OAuth Consumers MUST NOT include an
-            # oauth_body_hash parameter on requests with form-encoded
-            # request bodies."
-            self['oauth_body_hash'] = base64.b64encode(sha(self.body).digest())
-
-        if 'oauth_consumer_key' not in self:
-            self['oauth_consumer_key'] = consumer.key
-
-        if token and 'oauth_token' not in self:
-            self['oauth_token'] = token.key
-
-        self['oauth_signature_method'] = signature_method.name
-        self['oauth_signature'] = signature_method.sign(self, consumer, token)
- 
-    @classmethod
-    def make_timestamp(cls):
-        """Get seconds since epoch (UTC)."""
-        return str(int(time.time()))
- 
-    @classmethod
-    def make_nonce(cls):
-        """Generate pseudorandom number."""
-        return str(random.randint(0, 100000000))
- 
-    @classmethod
-    def from_request(cls, http_method, http_url, headers=None, parameters=None,
-            query_string=None):
-        """Combines multiple parameter sources."""
-        if parameters is None:
-            parameters = {}
- 
-        # Headers
-        if headers and 'Authorization' in headers:
-            auth_header = headers['Authorization']
-            # Check that the authorization header is OAuth.
-            if auth_header[:6] == 'OAuth ':
-                auth_header = auth_header[6:]
-                try:
-                    # Get the parameters from the header.
-                    header_params = cls._split_header(auth_header)
-                    parameters.update(header_params)
-                except:
-                    raise Error('Unable to parse OAuth parameters from '
-                        'Authorization header.')
- 
-        # GET or POST query string.
-        if query_string:
-            query_params = cls._split_url_string(query_string)
-            parameters.update(query_params)
- 
-        # URL parameters.
-        param_str = urlparse.urlparse(http_url)[4] # query
-        url_params = cls._split_url_string(param_str)
-        parameters.update(url_params)
- 
-        if parameters:
-            return cls(http_method, http_url, parameters)
- 
-        return None
- 
-    @classmethod
-    def from_consumer_and_token(cls, consumer, token=None,
-            http_method=HTTP_METHOD, http_url=None, parameters=None,
-            body='', is_form_encoded=False):
-        if not parameters:
-            parameters = {}
- 
-        defaults = {
-            'oauth_consumer_key': consumer.key,
-            'oauth_timestamp': cls.make_timestamp(),
-            'oauth_nonce': cls.make_nonce(),
-            'oauth_version': cls.version,
-        }
- 
-        defaults.update(parameters)
-        parameters = defaults
- 
-        if token:
-            parameters['oauth_token'] = token.key
-            if token.verifier:
-                parameters['oauth_verifier'] = token.verifier
- 
-        return Request(http_method, http_url, parameters, body=body, 
-                       is_form_encoded=is_form_encoded)
- 
-    @classmethod
-    def from_token_and_callback(cls, token, callback=None, 
-        http_method=HTTP_METHOD, http_url=None, parameters=None):
-
-        if not parameters:
-            parameters = {}
- 
-        parameters['oauth_token'] = token.key
- 
-        if callback:
-            parameters['oauth_callback'] = callback
- 
-        return cls(http_method, http_url, parameters)
- 
-    @staticmethod
-    def _split_header(header):
-        """Turn Authorization: header into parameters."""
-        params = {}
-        parts = header.split(',')
-        for param in parts:
-            # Ignore realm parameter.
-            if param.find('realm') > -1:
-                continue
-            # Remove whitespace.
-            param = param.strip()
-            # Split key-value.
-            param_parts = param.split('=', 1)
-            # Remove quotes and unescape the value.
-            params[param_parts[0]] = urllib.unquote(param_parts[1].strip('\"'))
-        return params
- 
-    @staticmethod
-    def _split_url_string(param_str):
-        """Turn URL string into parameters."""
-        parameters = parse_qs(param_str.encode('utf-8'), keep_blank_values=True)
-        for k, v in parameters.iteritems():
-            parameters[k] = urllib.unquote(v[0])
-        return parameters
-
-
-class Client(httplib2.Http):
-    """OAuthClient is a worker to attempt to execute a request."""
-
-    def __init__(self, consumer, token=None, cache=None, timeout=None,
-        proxy_info=None):
-
-        if consumer is not None and not isinstance(consumer, Consumer):
-            raise ValueError("Invalid consumer.")
-
-        if token is not None and not isinstance(token, Token):
-            raise ValueError("Invalid token.")
-
-        self.consumer = consumer
-        self.token = token
-        self.method = SignatureMethod_HMAC_SHA1()
-
-        httplib2.Http.__init__(self, cache=cache, timeout=timeout, proxy_info=proxy_info)
-
-    def set_signature_method(self, method):
-        if not isinstance(method, SignatureMethod):
-            raise ValueError("Invalid signature method.")
-
-        self.method = method
-
-    def request(self, uri, method="GET", body='', headers=None, 
-        redirections=httplib2.DEFAULT_MAX_REDIRECTS, connection_type=None):
-        DEFAULT_POST_CONTENT_TYPE = 'application/x-www-form-urlencoded'
-
-        if not isinstance(headers, dict):
-            headers = {}
-
-        if method == "POST":
-            headers['Content-Type'] = headers.get('Content-Type', 
-                DEFAULT_POST_CONTENT_TYPE)
-
-        is_form_encoded = \
-            headers.get('Content-Type') == 'application/x-www-form-urlencoded'
-
-        if is_form_encoded and body:
-            parameters = parse_qs(body)
-        else:
-            parameters = None
-
-        req = Request.from_consumer_and_token(self.consumer, 
-            token=self.token, http_method=method, http_url=uri, 
-            parameters=parameters, body=body, is_form_encoded=is_form_encoded)
-
-        req.sign_request(self.method, self.consumer, self.token)
-
-        schema, rest = urllib.splittype(uri)
-        if rest.startswith('//'):
-            hierpart = '//'
-        else:
-            hierpart = ''
-        host, rest = urllib.splithost(rest)
-
-        realm = schema + ':' + hierpart + host
-
-        if is_form_encoded:
-            body = req.to_postdata()
-        elif method == "GET":
-            uri = req.to_url()
-        else:
-            headers.update(req.to_header(realm=realm))
-
-        return httplib2.Http.request(self, uri, method=method, body=body,
-            headers=headers, redirections=redirections,
-            connection_type=connection_type)
-
-
-class Server(object):
-    """A skeletal implementation of a service provider, providing protected
-    resources to requests from authorized consumers.
- 
-    This class implements the logic to check requests for authorization. You
-    can use it with your web server or web framework to protect certain
-    resources with OAuth.
-    """
-
-    timestamp_threshold = 300 # In seconds, five minutes.
-    version = OAUTH_VERSION
-    signature_methods = None
-
-    def __init__(self, signature_methods=None):
-        self.signature_methods = signature_methods or {}
-
-    def add_signature_method(self, signature_method):
-        self.signature_methods[signature_method.name] = signature_method
-        return self.signature_methods
-
-    def verify_request(self, request, consumer, token):
-        """Verifies an api call and checks all the parameters."""
-
-        self._check_version(request)
-        self._check_signature(request, consumer, token)
-        parameters = request.get_nonoauth_parameters()
-        return parameters
-
-    def build_authenticate_header(self, realm=''):
-        """Optional support for the authenticate header."""
-        return {'WWW-Authenticate': 'OAuth realm="%s"' % realm}
-
-    def _check_version(self, request):
-        """Verify the correct version of the request for this server."""
-        version = self._get_version(request)
-        if version and version != self.version:
-            raise Error('OAuth version %s not supported.' % str(version))
-
-    def _get_version(self, request):
-        """Return the version of the request for this server."""
-        try:
-            version = request.get_parameter('oauth_version')
-        except:
-            version = OAUTH_VERSION
-
-        return version
-
-    def _get_signature_method(self, request):
-        """Figure out the signature with some defaults."""
-        try:
-            signature_method = request.get_parameter('oauth_signature_method')
-        except:
-            signature_method = SIGNATURE_METHOD
-
-        try:
-            # Get the signature method object.
-            signature_method = self.signature_methods[signature_method]
-        except:
-            signature_method_names = ', '.join(self.signature_methods.keys())
-            raise Error('Signature method %s not supported try one of the following: %s' % (signature_method, signature_method_names))
-
-        return signature_method
-
-    def _get_verifier(self, request):
-        return request.get_parameter('oauth_verifier')
-
-    def _check_signature(self, request, consumer, token):
-        timestamp, nonce = request._get_timestamp_nonce()
-        self._check_timestamp(timestamp)
-        signature_method = self._get_signature_method(request)
-
-        try:
-            signature = request.get_parameter('oauth_signature')
-        except:
-            raise MissingSignature('Missing oauth_signature.')
-
-        # Validate the signature.
-        valid = signature_method.check(request, consumer, token, signature)
-
-        if not valid:
-            key, base = signature_method.signing_base(request, consumer, token)
-
-            raise Error('Invalid signature. Expected signature base ' 
-                'string: %s' % base)
-
-    def _check_timestamp(self, timestamp):
-        """Verify that timestamp is recentish."""
-        timestamp = int(timestamp)
-        now = int(time.time())
-        lapsed = now - timestamp
-        if lapsed > self.timestamp_threshold:
-            raise Error('Expired timestamp: given %d and now %s has a '
-                'greater difference than threshold %d' % (timestamp, now, 
-                    self.timestamp_threshold))
-
-
-class SignatureMethod(object):
-    """A way of signing requests.
- 
-    The OAuth protocol lets consumers and service providers pick a way to sign
-    requests. This interface shows the methods expected by the other `oauth`
-    modules for signing requests. Subclass it and implement its methods to
-    provide a new way to sign requests.
-    """
-
-    def signing_base(self, request, consumer, token):
-        """Calculates the string that needs to be signed.
-
-        This method returns a 2-tuple containing the starting key for the
-        signing and the message to be signed. The latter may be used in error
-        messages to help clients debug their software.
-
-        """
-        raise NotImplementedError
-
-    def sign(self, request, consumer, token):
-        """Returns the signature for the given request, based on the consumer
-        and token also provided.
-
-        You should use your implementation of `signing_base()` to build the
-        message to sign. Otherwise it may be less useful for debugging.
-
-        """
-        raise NotImplementedError
-
-    def check(self, request, consumer, token, signature):
-        """Returns whether the given signature is the correct signature for
-        the given consumer and token signing the given request."""
-        built = self.sign(request, consumer, token)
-        return built == signature
-
-
-class SignatureMethod_HMAC_SHA1(SignatureMethod):
-    name = 'HMAC-SHA1'
-
-    def signing_base(self, request, consumer, token):
-        if not hasattr(request, 'normalized_url') or request.normalized_url is None:
-            raise ValueError("Base URL for request is not set.")
-
-        sig = (
-            escape(request.method),
-            escape(request.normalized_url),
-            escape(request.get_normalized_parameters()),
-        )
-
-        key = '%s&' % escape(consumer.secret)
-        if token:
-            key += escape(token.secret)
-        raw = '&'.join(sig)
-        return key, raw
-
-    def sign(self, request, consumer, token):
-        """Builds the base signature string."""
-        key, raw = self.signing_base(request, consumer, token)
-
-        hashed = hmac.new(key, raw, sha)
-
-        # Calculate the digest base 64.
-        return binascii.b2a_base64(hashed.digest())[:-1]
-
-
-class SignatureMethod_PLAINTEXT(SignatureMethod):
-
-    name = 'PLAINTEXT'
-
-    def signing_base(self, request, consumer, token):
-        """Concatenates the consumer key and secret with the token's
-        secret."""
-        sig = '%s&' % escape(consumer.secret)
-        if token:
-            sig = sig + escape(token.secret)
-        return sig, sig
-
-    def sign(self, request, consumer, token):
-        key, raw = self.signing_base(request, consumer, token)
-        return raw
+from .conf import OAUTH_VERSION, HTTP_METHOD, SIGNATURE_METHOD
+from .exc import Error, MissingSignature
+from .helper import build_authenticate_header, escape, \
+                    generate_timestamp, generate_nonce, generate_verifier, \
+                    setter
+from .xoauth import build_xoauth_string
+
+from .charset import to_unicode, to_utf8, \
+                     to_unicode_if_string, to_utf8_if_string, \
+                     to_unicode_optional_iterator, to_utf8_optional_iterator
+
+# classes
+from .consumer import Consumer
+from .token import Token
+from .request import Request
+from .client import Client
+from .server import Server
+from .signature import SignatureMethod, \
+                       SignatureMethod_HMAC_SHA1, SignatureMethod_PLAINTEXT
diff --git a/oauth2/charset.py b/oauth2/charset.py
new file mode 100644
index 00000000..d63536b3
--- /dev/null
+++ b/oauth2/charset.py
@@ -0,0 +1,91 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+def to_unicode(s):
+    """ Convert to unicode, raise exception with instructive error
+    message if s is not unicode, ascii, or utf-8. """
+    if not isinstance(s, unicode):
+        if not isinstance(s, str):
+            raise TypeError('You are required to pass either unicode or'
+                            ' string here, not: %r (%s)' % (type(s), s)
+                            )
+        try:
+            s = s.decode('utf-8')
+        except UnicodeDecodeError, le:
+            raise TypeError('You are required to pass either a unicode object'
+                            ' or a utf-8 string here. You passed a Python'
+                            ' string object which contained non-utf-8: %r.'
+                            ' The UnicodeDecodeError that resulted from'
+                            ' attempting to interpret it as utf-8 was: %s'
+                            % (s, le,)
+                            )
+    return s
+
+def to_utf8(s):
+    return to_unicode(s).encode('utf-8')
+
+def to_unicode_if_string(s):
+    if isinstance(s, basestring):
+        return to_unicode(s)
+    else:
+        return s
+
+def to_utf8_if_string(s):
+    if isinstance(s, basestring):
+        return to_utf8(s)
+    else:
+        return s
+
+def to_unicode_optional_iterator(x):
+    """
+    Raise TypeError if x is a str containing non-utf8 bytes or if x is
+    an iterable which contains such a str.
+    """
+    if isinstance(x, basestring):
+        return to_unicode(x)
+
+    try:
+        l = list(x)
+    except TypeError, e:
+        assert 'is not iterable' in str(e)
+        return x
+    else:
+        return [ to_unicode(e) for e in l ]
+
+def to_utf8_optional_iterator(x):
+    """
+    Raise TypeError if x is a str or if x is an iterable which
+    contains a str.
+    """
+    if isinstance(x, basestring):
+        return to_utf8(x)
+
+    try:
+        l = list(x)
+    except TypeError, e:
+        assert 'is not iterable' in str(e)
+        return x
+    else:
+        return [ to_utf8_if_string(e) for e in l ]
+
diff --git a/oauth2/client.py b/oauth2/client.py
new file mode 100644
index 00000000..05332cc1
--- /dev/null
+++ b/oauth2/client.py
@@ -0,0 +1,108 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import urllib
+import urlparse
+import httplib2
+
+try:
+    from urlparse import parse_qs
+    parse_qs # placate pyflakes
+except ImportError:
+    # fall back for Python 2.5
+    from cgi import parse_qs
+
+from .consumer import Consumer
+from .request import Request
+from .token import Token
+from .signature import SignatureMethod, SignatureMethod_HMAC_SHA1
+
+class Client(httplib2.Http):
+    """OAuthClient is a worker to attempt to execute a request."""
+
+    def __init__(self, consumer, token=None, cache=None, timeout=None,
+        proxy_info=None):
+
+        if consumer is not None and not isinstance(consumer, Consumer):
+            raise ValueError("Invalid consumer.")
+
+        if token is not None and not isinstance(token, Token):
+            raise ValueError("Invalid token.")
+
+        self.consumer = consumer
+        self.token = token
+        self.method = SignatureMethod_HMAC_SHA1()
+
+        httplib2.Http.__init__(self, cache=cache, timeout=timeout, proxy_info=proxy_info)
+
+    def set_signature_method(self, method):
+        if not isinstance(method, SignatureMethod):
+            raise ValueError("Invalid signature method.")
+
+        self.method = method
+
+    def request(self, uri, method="GET", body='', headers=None, 
+        redirections=httplib2.DEFAULT_MAX_REDIRECTS, connection_type=None):
+        DEFAULT_POST_CONTENT_TYPE = 'application/x-www-form-urlencoded'
+
+        if not isinstance(headers, dict):
+            headers = {}
+
+        if method == "POST":
+            headers['Content-Type'] = headers.get('Content-Type', 
+                DEFAULT_POST_CONTENT_TYPE)
+
+        is_form_encoded = \
+            headers.get('Content-Type') == 'application/x-www-form-urlencoded'
+
+        if is_form_encoded and body:
+            parameters = parse_qs(body)
+        else:
+            parameters = None
+
+        req = Request.from_consumer_and_token(self.consumer, 
+            token=self.token, http_method=method, http_url=uri, 
+            parameters=parameters, body=body, is_form_encoded=is_form_encoded)
+
+        req.sign_request(self.method, self.consumer, self.token)
+
+        schema, rest = urllib.splittype(uri)
+        if rest.startswith('//'):
+            hierpart = '//'
+        else:
+            hierpart = ''
+        host, rest = urllib.splithost(rest)
+
+        realm = schema + ':' + hierpart + host
+
+        if is_form_encoded:
+            body = req.to_postdata()
+        elif method == "GET":
+            uri = req.to_url()
+        else:
+            headers.update(req.to_header(realm=realm))
+
+        return httplib2.Http.request(self, uri, method=method, body=body,
+            headers=headers, redirections=redirections,
+            connection_type=connection_type)
diff --git a/oauth2/conf.py b/oauth2/conf.py
new file mode 100644
index 00000000..d1140e54
--- /dev/null
+++ b/oauth2/conf.py
@@ -0,0 +1,3 @@
+OAUTH_VERSION = '1.0'  # Hi Blaine!
+HTTP_METHOD = 'GET'
+SIGNATURE_METHOD = 'PLAINTEXT'
diff --git a/oauth2/consumer.py b/oauth2/consumer.py
new file mode 100644
index 00000000..addac2d8
--- /dev/null
+++ b/oauth2/consumer.py
@@ -0,0 +1,61 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import urllib
+
+class Consumer(object):
+    """A consumer of OAuth-protected services.
+ 
+    The OAuth consumer is a "third-party" service that wants to access
+    protected resources from an OAuth service provider on behalf of an end
+    user. It's kind of the OAuth client.
+ 
+    Usually a consumer must be registered with the service provider by the
+    developer of the consumer software. As part of that process, the service
+    provider gives the consumer a *key* and a *secret* with which the consumer
+    software can identify itself to the service. The consumer will include its
+    key in each request to identify itself, but will use its secret only when
+    signing requests, to prove that the request is from that particular
+    registered consumer.
+ 
+    Once registered, the consumer can then use its consumer credentials to ask
+    the service provider for a request token, kicking off the OAuth
+    authorization process.
+    """
+
+    key = None
+    secret = None
+
+    def __init__(self, key, secret):
+        self.key = key
+        self.secret = secret
+
+        if self.key is None or self.secret is None:
+            raise ValueError("Key and secret must be set.")
+
+    def __str__(self):
+        data = {'oauth_consumer_key': self.key,
+            'oauth_consumer_secret': self.secret}
+
+        return urllib.urlencode(data)
diff --git a/oauth2/exc.py b/oauth2/exc.py
new file mode 100644
index 00000000..4b0cb80d
--- /dev/null
+++ b/oauth2/exc.py
@@ -0,0 +1,42 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+class Error(RuntimeError):
+    """Generic exception class."""
+
+    def __init__(self, message='OAuth error occurred.'):
+        self._message = message
+
+    @property
+    def message(self):
+        """A hack to get around the deprecation errors in 2.6."""
+        return self._message
+
+    def __str__(self):
+        return self._message
+
+
+class MissingSignature(Error):
+    pass
+
diff --git a/oauth2/helper.py b/oauth2/helper.py
new file mode 100644
index 00000000..2e9d835b
--- /dev/null
+++ b/oauth2/helper.py
@@ -0,0 +1,64 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import urllib
+import time
+import random
+
+def build_authenticate_header(realm=''):
+    """Optional WWW-Authenticate header (401 error)"""
+    return {'WWW-Authenticate': 'OAuth realm="%s"' % realm}
+
+def escape(s):
+    """Escape a URL including any /."""
+    return urllib.quote(s.encode('utf-8'), safe='~')
+
+def generate_timestamp():
+    """Get seconds since epoch (UTC)."""
+    return int(time.time())
+
+
+def generate_nonce(length=8):
+    """Generate pseudorandom number."""
+    return ''.join([str(random.randint(0, 9)) for i in range(length)])
+
+
+def generate_verifier(length=8):
+    """Generate pseudorandom number."""
+    return ''.join([str(random.randint(0, 9)) for i in range(length)])
+
+def setter(attr):
+    name = attr.__name__
+ 
+    def getter(self):
+        try:
+            return self.__dict__[name]
+        except KeyError:
+            raise AttributeError(name)
+ 
+    def deleter(self):
+        del self.__dict__[name]
+ 
+    return property(getter, attr, deleter)
+
diff --git a/oauth2/request.py b/oauth2/request.py
new file mode 100644
index 00000000..d48fa0e0
--- /dev/null
+++ b/oauth2/request.py
@@ -0,0 +1,337 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import base64
+import urllib
+import time
+import random
+import urlparse
+
+try:
+    from urlparse import parse_qs
+    parse_qs # placate pyflakes
+except ImportError:
+    # fall back for Python 2.5
+    from cgi import parse_qs
+
+try:
+    from hashlib import sha1
+    sha = sha1
+except ImportError:
+    # hashlib was added in Python 2.5
+    import sha
+
+
+from .conf import OAUTH_VERSION, HTTP_METHOD
+from .exc import Error
+from .charset import to_unicode, to_utf8, to_utf8_if_string, \
+                     to_unicode_optional_iterator, to_utf8_optional_iterator
+from .helper import escape, setter
+
+class Request(dict):
+ 
+    """The parameters and information for an HTTP request, suitable for
+    authorizing with OAuth credentials.
+ 
+    When a consumer wants to access a service's protected resources, it does
+    so using a signed HTTP request identifying itself (the consumer) with its
+    key, and providing an access token authorized by the end user to access
+    those resources.
+ 
+    """
+ 
+    version = OAUTH_VERSION
+
+    def __init__(self, method=HTTP_METHOD, url=None, parameters=None,
+                 body='', is_form_encoded=False):
+        if url is not None:
+            self.url = to_unicode(url)
+        self.method = method
+        if parameters is not None:
+            for k, v in parameters.iteritems():
+                k = to_unicode(k)
+                v = to_unicode_optional_iterator(v)
+                self[k] = v
+        self.body = body
+        self.is_form_encoded = is_form_encoded
+
+
+    @setter
+    def url(self, value):
+        self.__dict__['url'] = value
+        if value is not None:
+            scheme, netloc, path, params, query, fragment = urlparse.urlparse(value)
+
+            # Exclude default port numbers.
+            if scheme == 'http' and netloc[-3:] == ':80':
+                netloc = netloc[:-3]
+            elif scheme == 'https' and netloc[-4:] == ':443':
+                netloc = netloc[:-4]
+            if scheme not in ('http', 'https'):
+                raise ValueError("Unsupported URL %s (%s)." % (value, scheme))
+
+            # Normalized URL excludes params, query, and fragment.
+            self.normalized_url = urlparse.urlunparse((scheme, netloc, path, None, None, None))
+        else:
+            self.normalized_url = None
+            self.__dict__['url'] = None
+ 
+    @setter
+    def method(self, value):
+        self.__dict__['method'] = value.upper()
+ 
+    def _get_timestamp_nonce(self):
+        return self['oauth_timestamp'], self['oauth_nonce']
+ 
+    def get_nonoauth_parameters(self):
+        """Get any non-OAuth parameters."""
+        return dict([(k, v) for k, v in self.iteritems() 
+                    if not k.startswith('oauth_')])
+ 
+    def to_header(self, realm=''):
+        """Serialize as a header for an HTTPAuth request."""
+        oauth_params = ((k, v) for k, v in self.items() 
+                            if k.startswith('oauth_'))
+        stringy_params = ((k, escape(str(v))) for k, v in oauth_params)
+        header_params = ('%s="%s"' % (k, v) for k, v in stringy_params)
+        params_header = ', '.join(header_params)
+ 
+        auth_header = 'OAuth realm="%s"' % realm
+        if params_header:
+            auth_header = "%s, %s" % (auth_header, params_header)
+ 
+        return {'Authorization': auth_header}
+ 
+    def to_postdata(self):
+        """Serialize as post data for a POST request."""
+        d = {}
+        for k, v in self.iteritems():
+            d[k.encode('utf-8')] = to_utf8_optional_iterator(v)
+
+        # tell urlencode to deal with sequence values and map them correctly
+        # to resulting querystring. for example self["k"] = ["v1", "v2"] will
+        # result in 'k=v1&k=v2' and not k=%5B%27v1%27%2C+%27v2%27%5D
+        return urllib.urlencode(d, True).replace('+', '%20')
+ 
+    def to_url(self):
+        """Serialize as a URL for a GET request."""
+        base_url = urlparse.urlparse(self.url)
+        try:
+            query = base_url.query
+        except AttributeError:
+            # must be python <2.5
+            query = base_url[4]
+        query = parse_qs(query)
+        for k, v in self.items():
+            query.setdefault(k, []).append(v)
+        
+        try:
+            scheme = base_url.scheme
+            netloc = base_url.netloc
+            path = base_url.path
+            params = base_url.params
+            fragment = base_url.fragment
+        except AttributeError:
+            # must be python <2.5
+            scheme = base_url[0]
+            netloc = base_url[1]
+            path = base_url[2]
+            params = base_url[3]
+            fragment = base_url[5]
+        
+        url = (scheme, netloc, path, params,
+               urllib.urlencode(query, True), fragment)
+        return urlparse.urlunparse(url)
+
+    def get_parameter(self, parameter):
+        ret = self.get(parameter)
+        if ret is None:
+            raise Error('Parameter not found: %s' % parameter)
+
+        return ret
+
+    def get_normalized_parameters(self):
+        """Return a string that contains the parameters that must be signed."""
+        items = []
+        for key, value in self.iteritems():
+            if key == 'oauth_signature':
+                continue
+            # 1.0a/9.1.1 states that kvp must be sorted by key, then by value,
+            # so we unpack sequence values into multiple items for sorting.
+            if isinstance(value, basestring):
+                items.append((to_utf8_if_string(key), to_utf8(value)))
+            else:
+                try:
+                    value = list(value)
+                except TypeError, e:
+                    assert 'is not iterable' in str(e)
+                    items.append((to_utf8_if_string(key), to_utf8_if_string(value)))
+                else:
+                    items.extend((to_utf8_if_string(key), to_utf8_if_string(item)) for item in value)
+
+        # Include any query string parameters from the provided URL
+        query = urlparse.urlparse(self.url)[4]
+
+        url_items = self._split_url_string(query).items()
+        url_items = [(to_utf8(k), to_utf8(v)) for k, v in url_items if k != 'oauth_signature' ]
+        items.extend(url_items)
+
+        items.sort()
+        encoded_str = urllib.urlencode(items)
+        # Encode signature parameters per Oauth Core 1.0 protocol
+        # spec draft 7, section 3.6
+        # (http://tools.ietf.org/html/draft-hammer-oauth-07#section-3.6)
+        # Spaces must be encoded with "%20" instead of "+"
+        return encoded_str.replace('+', '%20').replace('%7E', '~')
+
+    def sign_request(self, signature_method, consumer, token):
+        """Set the signature parameter to the result of sign."""
+
+        if not self.is_form_encoded:
+            # according to
+            # http://oauth.googlecode.com/svn/spec/ext/body_hash/1.0/oauth-bodyhash.html
+            # section 4.1.1 "OAuth Consumers MUST NOT include an
+            # oauth_body_hash parameter on requests with form-encoded
+            # request bodies."
+            self['oauth_body_hash'] = base64.b64encode(sha(self.body).digest())
+
+        if 'oauth_consumer_key' not in self:
+            self['oauth_consumer_key'] = consumer.key
+
+        if token and 'oauth_token' not in self:
+            self['oauth_token'] = token.key
+
+        self['oauth_signature_method'] = signature_method.name
+        self['oauth_signature'] = signature_method.sign(self, consumer, token)
+
+    @classmethod
+    def make_timestamp(cls):
+        """Get seconds since epoch (UTC)."""
+        return str(int(time.time()))
+ 
+    @classmethod
+    def make_nonce(cls):
+        """Generate pseudorandom number."""
+        return str(random.randint(0, 100000000))
+ 
+    @classmethod
+    def from_request(cls, http_method, http_url, headers=None, parameters=None,
+            query_string=None):
+        """Combines multiple parameter sources."""
+        if parameters is None:
+            parameters = {}
+ 
+        # Headers
+        if headers and 'Authorization' in headers:
+            auth_header = headers['Authorization']
+            # Check that the authorization header is OAuth.
+            if auth_header[:6] == 'OAuth ':
+                auth_header = auth_header[6:]
+                try:
+                    # Get the parameters from the header.
+                    header_params = cls._split_header(auth_header)
+                    parameters.update(header_params)
+                except:
+                    raise Error('Unable to parse OAuth parameters from '
+                        'Authorization header.')
+ 
+        # GET or POST query string.
+        if query_string:
+            query_params = cls._split_url_string(query_string)
+            parameters.update(query_params)
+ 
+        # URL parameters.
+        param_str = urlparse.urlparse(http_url)[4] # query
+        url_params = cls._split_url_string(param_str)
+        parameters.update(url_params)
+ 
+        if parameters:
+            return cls(http_method, http_url, parameters)
+ 
+        return None
+ 
+    @classmethod
+    def from_consumer_and_token(cls, consumer, token=None,
+            http_method=HTTP_METHOD, http_url=None, parameters=None,
+            body='', is_form_encoded=False):
+        if not parameters:
+            parameters = {}
+ 
+        defaults = {
+            'oauth_consumer_key': consumer.key,
+            'oauth_timestamp': cls.make_timestamp(),
+            'oauth_nonce': cls.make_nonce(),
+            'oauth_version': cls.version,
+        }
+ 
+        defaults.update(parameters)
+        parameters = defaults
+ 
+        if token:
+            parameters['oauth_token'] = token.key
+            if token.verifier:
+                parameters['oauth_verifier'] = token.verifier
+ 
+        return Request(http_method, http_url, parameters, body=body, 
+                       is_form_encoded=is_form_encoded)
+ 
+    @classmethod
+    def from_token_and_callback(cls, token, callback=None, 
+        http_method=HTTP_METHOD, http_url=None, parameters=None):
+
+        if not parameters:
+            parameters = {}
+ 
+        parameters['oauth_token'] = token.key
+ 
+        if callback:
+            parameters['oauth_callback'] = callback
+ 
+        return cls(http_method, http_url, parameters)
+ 
+    @staticmethod
+    def _split_header(header):
+        """Turn Authorization: header into parameters."""
+        params = {}
+        parts = header.split(',')
+        for param in parts:
+            # Ignore realm parameter.
+            if param.find('realm') > -1:
+                continue
+            # Remove whitespace.
+            param = param.strip()
+            # Split key-value.
+            param_parts = param.split('=', 1)
+            # Remove quotes and unescape the value.
+            params[param_parts[0]] = urllib.unquote(param_parts[1].strip('\"'))
+        return params
+ 
+    @staticmethod
+    def _split_url_string(param_str):
+        """Turn URL string into parameters."""
+        parameters = parse_qs(param_str.encode('utf-8'), keep_blank_values=True)
+        for k, v in parameters.iteritems():
+            parameters[k] = urllib.unquote(v[0])
+        return parameters
+
diff --git a/oauth2/server.py b/oauth2/server.py
new file mode 100644
index 00000000..2a551010
--- /dev/null
+++ b/oauth2/server.py
@@ -0,0 +1,123 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import time
+
+from .conf import OAUTH_VERSION, SIGNATURE_METHOD
+from .exc import Error, MissingSignature
+
+class Server(object):
+    """A skeletal implementation of a service provider, providing protected
+    resources to requests from authorized consumers.
+ 
+    This class implements the logic to check requests for authorization. You
+    can use it with your web server or web framework to protect certain
+    resources with OAuth.
+    """
+
+    timestamp_threshold = 300 # In seconds, five minutes.
+    version = OAUTH_VERSION
+    signature_methods = None
+
+    def __init__(self, signature_methods=None):
+        self.signature_methods = signature_methods or {}
+
+    def add_signature_method(self, signature_method):
+        self.signature_methods[signature_method.name] = signature_method
+        return self.signature_methods
+
+    def verify_request(self, request, consumer, token):
+        """Verifies an api call and checks all the parameters."""
+
+        self._check_version(request)
+        self._check_signature(request, consumer, token)
+        parameters = request.get_nonoauth_parameters()
+        return parameters
+
+    def build_authenticate_header(self, realm=''):
+        """Optional support for the authenticate header."""
+        return {'WWW-Authenticate': 'OAuth realm="%s"' % realm}
+
+    def _check_version(self, request):
+        """Verify the correct version of the request for this server."""
+        version = self._get_version(request)
+        if version and version != self.version:
+            raise Error('OAuth version %s not supported.' % str(version))
+
+    def _get_version(self, request):
+        """Return the version of the request for this server."""
+        try:
+            version = request.get_parameter('oauth_version')
+        except:
+            version = OAUTH_VERSION
+
+        return version
+
+    def _get_signature_method(self, request):
+        """Figure out the signature with some defaults."""
+        try:
+            signature_method = request.get_parameter('oauth_signature_method')
+        except:
+            signature_method = SIGNATURE_METHOD
+
+        try:
+            # Get the signature method object.
+            signature_method = self.signature_methods[signature_method]
+        except:
+            signature_method_names = ', '.join(self.signature_methods.keys())
+            raise Error('Signature method %s not supported try one of the following: %s' % (signature_method, signature_method_names))
+
+        return signature_method
+
+    def _get_verifier(self, request):
+        return request.get_parameter('oauth_verifier')
+
+    def _check_signature(self, request, consumer, token):
+        timestamp, nonce = request._get_timestamp_nonce()
+        self._check_timestamp(timestamp)
+        signature_method = self._get_signature_method(request)
+
+        try:
+            signature = request.get_parameter('oauth_signature')
+        except:
+            raise MissingSignature('Missing oauth_signature.')
+
+        # Validate the signature.
+        valid = signature_method.check(request, consumer, token, signature)
+
+        if not valid:
+            key, base = signature_method.signing_base(request, consumer, token)
+
+            raise Error('Invalid signature. Expected signature base ' 
+                'string: %s' % base)
+
+    def _check_timestamp(self, timestamp):
+        """Verify that timestamp is recentish."""
+        timestamp = int(timestamp)
+        now = int(time.time())
+        lapsed = now - timestamp
+        if lapsed > self.timestamp_threshold:
+            raise Error('Expired timestamp: given %d and now %s has a '
+                'greater difference than threshold %d' % (timestamp, now, 
+                    self.timestamp_threshold))
diff --git a/oauth2/signature.py b/oauth2/signature.py
new file mode 100644
index 00000000..20bfd989
--- /dev/null
+++ b/oauth2/signature.py
@@ -0,0 +1,116 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import hmac
+import binascii
+
+try:
+    from hashlib import sha1
+    sha = sha1
+except ImportError:
+    # hashlib was added in Python 2.5
+    import sha
+
+from .helper import escape
+
+class SignatureMethod(object):
+    """A way of signing requests.
+ 
+    The OAuth protocol lets consumers and service providers pick a way to sign
+    requests. This interface shows the methods expected by the other `oauth`
+    modules for signing requests. Subclass it and implement its methods to
+    provide a new way to sign requests.
+    """
+
+    def signing_base(self, request, consumer, token):
+        """Calculates the string that needs to be signed.
+
+        This method returns a 2-tuple containing the starting key for the
+        signing and the message to be signed. The latter may be used in error
+        messages to help clients debug their software.
+
+        """
+        raise NotImplementedError
+
+    def sign(self, request, consumer, token):
+        """Returns the signature for the given request, based on the consumer
+        and token also provided.
+
+        You should use your implementation of `signing_base()` to build the
+        message to sign. Otherwise it may be less useful for debugging.
+
+        """
+        raise NotImplementedError
+
+    def check(self, request, consumer, token, signature):
+        """Returns whether the given signature is the correct signature for
+        the given consumer and token signing the given request."""
+        built = self.sign(request, consumer, token)
+        return built == signature
+
+
+class SignatureMethod_HMAC_SHA1(SignatureMethod):
+    name = 'HMAC-SHA1'
+
+    def signing_base(self, request, consumer, token):
+        if not hasattr(request, 'normalized_url') or request.normalized_url is None:
+            raise ValueError("Base URL for request is not set.")
+
+        sig = (
+            escape(request.method),
+            escape(request.normalized_url),
+            escape(request.get_normalized_parameters()),
+        )
+
+        key = '%s&' % escape(consumer.secret)
+        if token:
+            key += escape(token.secret)
+        raw = '&'.join(sig)
+        return key, raw
+
+    def sign(self, request, consumer, token):
+        """Builds the base signature string."""
+        key, raw = self.signing_base(request, consumer, token)
+
+        hashed = hmac.new(key, raw, sha)
+
+        # Calculate the digest base 64.
+        return binascii.b2a_base64(hashed.digest())[:-1]
+
+
+class SignatureMethod_PLAINTEXT(SignatureMethod):
+
+    name = 'PLAINTEXT'
+
+    def signing_base(self, request, consumer, token):
+        """Concatenates the consumer key and secret with the token's
+        secret."""
+        sig = '%s&' % escape(consumer.secret)
+        if token:
+            sig = sig + escape(token.secret)
+        return sig, sig
+
+    def sign(self, request, consumer, token):
+        key, raw = self.signing_base(request, consumer, token)
+        return raw
diff --git a/oauth2/token.py b/oauth2/token.py
new file mode 100644
index 00000000..84f07b34
--- /dev/null
+++ b/oauth2/token.py
@@ -0,0 +1,137 @@
+"""
+The MIT License
+
+Copyright (c) 2007-2010 Leah Culver, Joe Stump, Mark Paschal, Vic Fryzel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+"""
+
+import urllib
+import urlparse
+
+try:
+    from urlparse import parse_qs
+    parse_qs # placate pyflakes
+except ImportError:
+    # fall back for Python 2.5
+    from cgi import parse_qs
+
+
+from .helper import generate_verifier
+
+class Token(object):
+    """An OAuth credential used to request authorization or a protected
+    resource.
+ 
+    Tokens in OAuth comprise a *key* and a *secret*. The key is included in
+    requests to identify the token being used, but the secret is used only in
+    the signature, to prove that the requester is who the server gave the
+    token to.
+ 
+    When first negotiating the authorization, the consumer asks for a *request
+    token* that the live user authorizes with the service provider. The
+    consumer then exchanges the request token for an *access token* that can
+    be used to access protected resources.
+    """
+
+    key = None
+    secret = None
+    callback = None
+    callback_confirmed = None
+    verifier = None
+
+    def __init__(self, key, secret):
+        self.key = key
+        self.secret = secret
+
+        if self.key is None or self.secret is None:
+            raise ValueError("Key and secret must be set.")
+
+    def set_callback(self, callback):
+        self.callback = callback
+        self.callback_confirmed = 'true'
+
+    def set_verifier(self, verifier=None):
+        if verifier is not None:
+            self.verifier = verifier
+        else:
+            self.verifier = generate_verifier()
+
+    def get_callback_url(self):
+        if self.callback and self.verifier:
+            # Append the oauth_verifier.
+            parts = urlparse.urlparse(self.callback)
+            scheme, netloc, path, params, query, fragment = parts[:6]
+            if query:
+                query = '%s&oauth_verifier=%s' % (query, self.verifier)
+            else:
+                query = 'oauth_verifier=%s' % self.verifier
+            return urlparse.urlunparse((scheme, netloc, path, params,
+                query, fragment))
+        return self.callback
+
+    def to_string(self):
+        """Returns this token as a plain string, suitable for storage.
+ 
+        The resulting string includes the token's secret, so you should never
+        send or store this string where a third party can read it.
+        """
+
+        data = {
+            'oauth_token': self.key,
+            'oauth_token_secret': self.secret,
+        }
+
+        if self.callback_confirmed is not None:
+            data['oauth_callback_confirmed'] = self.callback_confirmed
+        return urllib.urlencode(data)
+ 
+    @staticmethod
+    def from_string(s):
+        """Deserializes a token from a string like one returned by
+        `to_string()`."""
+
+        if not len(s):
+            raise ValueError("Invalid parameter string.")
+
+        params = parse_qs(s, keep_blank_values=False)
+        if not len(params):
+            raise ValueError("Invalid parameter string.")
+
+        try:
+            key = params['oauth_token'][0]
+        except Exception:
+            raise ValueError("'oauth_token' not found in OAuth request.")
+
+        try:
+            secret = params['oauth_token_secret'][0]
+        except Exception:
+            raise ValueError("'oauth_token_secret' not found in " 
+                "OAuth request.")
+
+        token = Token(key, secret)
+        try:
+            token.callback_confirmed = params['oauth_callback_confirmed'][0]
+        except KeyError:
+            pass  # 1.0, no callback confirmed.
+        return token
+
+    def __str__(self):
+        return self.to_string()
+
diff --git a/oauth2/xoauth.py b/oauth2/xoauth.py
new file mode 100644
index 00000000..26088de0
--- /dev/null
+++ b/oauth2/xoauth.py
@@ -0,0 +1,19 @@
+from .helper import escape
+from .request import Request
+from .signature import SignatureMethod_HMAC_SHA1
+
+def build_xoauth_string(url, consumer, token=None):
+    """Build an XOAUTH string for use in SMTP/IMPA authentication."""
+    request = Request.from_consumer_and_token(consumer, token,
+        "GET", url)
+
+    signing_method = SignatureMethod_HMAC_SHA1()
+    request.sign_request(signing_method, consumer, token)
+
+    params = []
+    for k, v in sorted(request.iteritems()):
+        if v is not None:
+            params.append('%s="%s"' % (k, escape(v)))
+
+    return "%s %s %s" % ("GET", url, ','.join(params))
+
