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Python Source | 2009-02-11 | 64.4 KB | 1,627 lines

# # Copyright (C) 2006,2008 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """GDataService provides CRUD ops. and programmatic login for GData services. Error: A base exception class for all exceptions in the gdata_client module. CaptchaRequired: This exception is thrown when a login attempt results in a captcha challenge from the ClientLogin service. When this exception is thrown, the captcha_token and captcha_url are set to the values provided in the server's response. BadAuthentication: Raised when a login attempt is made with an incorrect username or password. NotAuthenticated: Raised if an operation requiring authentication is called before a user has authenticated. NonAuthSubToken: Raised if a method to modify an AuthSub token is used when the user is either not authenticated or is authenticated through another authentication mechanism. NonOAuthToken: Raised if a method to modify an OAuth token is used when the user is either not authenticated or is authenticated through another authentication mechanism. RequestError: Raised if a CRUD request returned a non-success code. UnexpectedReturnType: Raised if the response from the server was not of the desired type. For example, this would be raised if the server sent a feed when the client requested an entry. GDataService: Encapsulates user credentials needed to perform insert, update and delete operations with the GData API. An instance can perform user authentication, query, insertion, deletion, and update. Query: Eases query URI creation by allowing URI parameters to be set as dictionary attributes. For example a query with a feed of '/base/feeds/snippets' and ['bq'] set to 'digital camera' will produce '/base/feeds/snippets?bq=digital+camera' when .ToUri() is called on it. """ __author__ = 'api.jscudder (Jeffrey Scudder)' import re import urllib import urlparse try: from xml.etree import cElementTree as ElementTree except ImportError: try: import cElementTree as ElementTree except ImportError: try: from xml.etree import ElementTree except ImportError: from elementtree import ElementTree import atom.service import gdata import atom import atom.http_interface import atom.token_store import gdata.auth AUTH_SERVER_HOST = 'https://www.google.com' # When requesting an AuthSub token, it is often helpful to track the scope # which is being requested. One way to accomplish this is to add a URL # parameter to the 'next' URL which contains the requested scope. This # constant is the default name (AKA key) for the URL parameter. SCOPE_URL_PARAM_NAME = 'authsub_token_scope' # When requesting an OAuth access token or authorization of an existing OAuth # request token, it is often helpful to track the scope(s) which is/are being # requested. One way to accomplish this is to add a URL parameter to the # 'callback' URL which contains the requested scope. This constant is the # default name (AKA key) for the URL parameter. OAUTH_SCOPE_URL_PARAM_NAME = 'oauth_token_scope' # Maps the service names used in ClientLogin to scope URLs. CLIENT_LOGIN_SCOPES = { 'cl': [ # Google Calendar 'https://www.google.com/calendar/feeds/', 'http://www.google.com/calendar/feeds/'], 'gbase': [ # Google Base 'http://base.google.com/base/feeds/', 'http://www.google.com/base/feeds/'], 'blogger': [ # Blogger 'http://www.blogger.com/feeds/'], 'codesearch': [ # Google Code Search 'http://www.google.com/codesearch/feeds/'], 'cp': [ # Contacts API 'https://www.google.com/m8/feeds/', 'http://www.google.com/m8/feeds/'], 'finance': [ # Google Finance 'http://finance.google.com/finance/feeds/'], 'health': [ # Google Health 'https://www.google.com/health/feeds/'], 'writely': [ # Documents List API 'https://docs.google.com/feeds/', 'http://docs.google.com/feeds/'], 'lh2': [ # Picasa Web Albums 'http://picasaweb.google.com/data/'], 'apps': [ # Google Apps Provisioning API 'http://www.google.com/a/feeds/', 'https://www.google.com/a/feeds/', 'http://apps-apis.google.com/a/feeds/', 'https://apps-apis.google.com/a/feeds/'], 'weaver': [ # Health H9 Sandbox 'https://www.google.com/h9/'], 'wise': [ # Spreadsheets Data API 'https://spreadsheets.google.com/feeds/', 'http://spreadsheets.google.com/feeds/'], 'sitemaps': [ # Google Webmaster Tools 'https://www.google.com/webmasters/tools/feeds/'], 'youtube': [ # YouTube 'http://gdata.youtube.com/feeds/api/', 'http://uploads.gdata.youtube.com/feeds/api', 'http://gdata.youtube.com/action/GetUploadToken']} def lookup_scopes(service_name): """Finds the scope URLs for the desired service. In some cases, an unknown service may be used, and in those cases this function will return None. """ if service_name in CLIENT_LOGIN_SCOPES: return CLIENT_LOGIN_SCOPES[service_name] return None # Module level variable specifies which module should be used by GDataService # objects to make HttpRequests. This setting can be overridden on each # instance of GDataService. # This module level variable is deprecated. Reassign the http_client member # of a GDataService object instead. http_request_handler = atom.service class Error(Exception): pass class CaptchaRequired(Error): pass class BadAuthentication(Error): pass class NotAuthenticated(Error): pass class NonAuthSubToken(Error): pass class NonOAuthToken(Error): pass class RequestError(Error): pass class UnexpectedReturnType(Error): pass class BadAuthenticationServiceURL(Error): pass class FetchingOAuthRequestTokenFailed(RequestError): pass class TokenUpgradeFailed(RequestError): pass class RevokingOAuthTokenFailed(RequestError): pass class AuthorizationRequired(Error): pass class TokenHadNoScope(Error): pass class GDataService(atom.service.AtomService): """Contains elements needed for GData login and CRUD request headers. Maintains additional headers (tokens for example) needed for the GData services to allow a user to perform inserts, updates, and deletes. """ # The hander member is deprecated, use http_client instead. handler = None # The auth_token member is deprecated, use the token_store instead. auth_token = None # The tokens dict is deprecated in favor of the token_store. tokens = None def __init__(self, email=None, password=None, account_type='HOSTED_OR_GOOGLE', service=None, auth_service_url=None, source=None, server=None, additional_headers=None, handler=None, tokens=None, http_client=None, token_store=None): """Creates an object of type GDataService. Args: email: string (optional) The user's email address, used for authentication. password: string (optional) The user's password. account_type: string (optional) The type of account to use. Use 'GOOGLE' for regular Google accounts or 'HOSTED' for Google Apps accounts, or 'HOSTED_OR_GOOGLE' to try finding a HOSTED account first and, if it doesn't exist, try finding a regular GOOGLE account. Default value: 'HOSTED_OR_GOOGLE'. service: string (optional) The desired service for which credentials will be obtained. auth_service_url: string (optional) User-defined auth token request URL allows users to explicitly specify where to send auth token requests. source: string (optional) The name of the user's application. server: string (optional) The name of the server to which a connection will be opened. Default value: 'base.google.com'. additional_headers: dictionary (optional) Any additional headers which should be included with CRUD operations. handler: module (optional) This parameter is deprecated and has been replaced by http_client. tokens: This parameter is deprecated, calls should be made to token_store instead. http_client: An object responsible for making HTTP requests using a request method. If none is provided, a new instance of atom.http.ProxiedHttpClient will be used. token_store: Keeps a collection of authorization tokens which can be applied to requests for a specific URLs. Critical methods are find_token based on a URL (atom.url.Url or a string), add_token, and remove_token. """ atom.service.AtomService.__init__(self, http_client=http_client, token_store=token_store) self.email = email self.password = password self.account_type = account_type self.service = service self.auth_service_url = auth_service_url self.server = server self.additional_headers = additional_headers or {} self._oauth_input_params = None self.__SetSource(source) self.__captcha_token = None self.__captcha_url = None self.__gsessionid = None if http_request_handler.__name__ == 'gdata.urlfetch': import gdata.alt.appengine self.http_client = gdata.alt.appengine.AppEngineHttpClient() # Define properties for GDataService def _SetAuthSubToken(self, auth_token, scopes=None): """Deprecated, use SetAuthSubToken instead.""" self.SetAuthSubToken(auth_token, scopes=scopes) def __SetAuthSubToken(self, auth_token, scopes=None): """Deprecated, use SetAuthSubToken instead.""" self._SetAuthSubToken(auth_token, scopes=scopes) def _GetAuthToken(self): """Returns the auth token used for authenticating requests. Returns: string """ current_scopes = lookup_scopes(self.service) if current_scopes: token = self.token_store.find_token(current_scopes[0]) if hasattr(token, 'auth_header'): return token.auth_header return None def _GetCaptchaToken(self): """Returns a captcha token if the most recent login attempt generated one. The captcha token is only set if the Programmatic Login attempt failed because the Google service issued a captcha challenge. Returns: string """ return self.__captcha_token def __GetCaptchaToken(self): return self._GetCaptchaToken() captcha_token = property(__GetCaptchaToken, doc="""Get the captcha token for a login request.""") def _GetCaptchaURL(self): """Returns the URL of the captcha image if a login attempt generated one. The captcha URL is only set if the Programmatic Login attempt failed because the Google service issued a captcha challenge. Returns: string """ return self.__captcha_url def __GetCaptchaURL(self): return self._GetCaptchaURL() captcha_url = property(__GetCaptchaURL, doc="""Get the captcha URL for a login request.""") def SetOAuthInputParameters(self, signature_method, consumer_key, consumer_secret=None, rsa_key=None, two_legged_oauth=False): """Sets parameters required for using OAuth authentication mechanism. NOTE: Though consumer_secret and rsa_key are optional, either of the two is required depending on the value of the signature_method. Args: signature_method: class which provides implementation for strategy class oauth.oauth.OAuthSignatureMethod. Signature method to be used for signing each request. Valid implementations are provided as the constants defined by gdata.auth.OAuthSignatureMethod. Currently they are gdata.auth.OAuthSignatureMethod.RSA_SHA1 and gdata.auth.OAuthSignatureMethod.HMAC_SHA1 consumer_key: string Domain identifying third_party web application. consumer_secret: string (optional) Secret generated during registration. Required only for HMAC_SHA1 signature method. rsa_key: string (optional) Private key required for RSA_SHA1 signature method. two_legged_oauth: string (default=False) Enables two-legged OAuth process. """ self._oauth_input_params = gdata.auth.OAuthInputParams( signature_method, consumer_key, consumer_secret=consumer_secret, rsa_key=rsa_key) if two_legged_oauth: oauth_token = gdata.auth.OAuthToken( oauth_input_params=self._oauth_input_params) self.SetOAuthToken(oauth_token) def FetchOAuthRequestToken(self, scopes=None, extra_parameters=None, request_url='%s/accounts/OAuthGetRequestToken' % \ AUTH_SERVER_HOST): """Fetches OAuth request token and returns it. Args: scopes: string or list of string base URL(s) of the service(s) to be accessed. If None, then this method tries to determine the scope(s) from the current service. extra_parameters: dict (optional) key-value pairs as any additional parameters to be included in the URL and signature while making a request for fetching an OAuth request token. All the OAuth parameters are added by default. But if provided through this argument, any default parameters will be overwritten. For e.g. a default parameter oauth_version 1.0 can be overwritten if extra_parameters = {'oauth_version': '2.0'} request_url: Request token URL. The default is 'https://www.google.com/accounts/OAuthGetRequestToken'. Returns: The fetched request token as a gdata.auth.OAuthToken object. Raises: FetchingOAuthRequestTokenFailed if the server responded to the request with an error. """ if scopes is None: scopes = lookup_scopes(self.service) if not isinstance(scopes, (list, tuple)): scopes = [scopes,] request_token_url = gdata.auth.GenerateOAuthRequestTokenUrl( self._oauth_input_params, scopes, request_token_url=request_url, extra_parameters=extra_parameters) response = self.http_client.request('GET', str(request_token_url)) if response.status == 200: token = gdata.auth.OAuthToken() token.set_token_string(response.read()) token.scopes = scopes token.oauth_input_params = self._oauth_input_params return token error = { 'status': response.status, 'reason': 'Non 200 response on upgrade', 'body': response.read() } raise FetchingOAuthRequestTokenFailed(error) def SetOAuthToken(self, oauth_token): """Attempts to set the current token and add it to the token store. The oauth_token can be any OAuth token i.e. unauthorized request token, authorized request token or access token. This method also attempts to add the token to the token store. Use this method any time you want the current token to point to the oauth_token passed. For e.g. call this method with the request token you receive from FetchOAuthRequestToken. Args: request_token: gdata.auth.OAuthToken OAuth request token. """ if self.auto_set_current_token: self.current_token = oauth_token if self.auto_store_tokens: self.token_store.add_token(oauth_token) def GenerateOAuthAuthorizationURL( self, request_token=None, callback_url=None, extra_params=None, include_scopes_in_callback=False, scopes_param_prefix=OAUTH_SCOPE_URL_PARAM_NAME, request_url='%s/accounts/OAuthAuthorizeToken' % AUTH_SERVER_HOST): """Generates URL at which user will login to authorize the request token. Args: request_token: gdata.auth.OAuthToken (optional) OAuth request token. If not specified, then the current token will be used if it is of type <gdata.auth.OAuthToken>, else it is found by looking in the token_store by looking for a token for the current scope. callback_url: string (optional) The URL user will be sent to after logging in and granting access. extra_params: dict (optional) Additional parameters to be sent. include_scopes_in_callback: Boolean (default=False) if set to True, and if 'callback_url' is present, the 'callback_url' will be modified to include the scope(s) from the request token as a URL parameter. The key for the 'callback' URL's scope parameter will be OAUTH_SCOPE_URL_PARAM_NAME. The benefit of including the scope URL as a parameter to the 'callback' URL, is that the page which receives the OAuth token will be able to tell which URLs the token grants access to. scopes_param_prefix: string (default='oauth_token_scope') The URL parameter key which maps to the list of valid scopes for the token. This URL parameter will be included in the callback URL along with the scopes of the token as value if include_scopes_in_callback=True. request_url: Authorization URL. The default is 'https://www.google.com/accounts/OAuthAuthorizeToken'. Returns: A string URL at which the user is required to login. Raises: NonOAuthToken if the user's request token is not an OAuth token or if a request token was not available. """ if request_token and not isinstance(request_token, gdata.auth.OAuthToken): raise NonOAuthToken if not request_token: if isinstance(self.current_token, gdata.auth.OAuthToken): request_token = self.current_token else: current_scopes = lookup_scopes(self.service) if current_scopes: token = self.token_store.find_token(current_scopes[0]) if isinstance(token, gdata.auth.OAuthToken): request_token = token if not request_token: raise NonOAuthToken return str(gdata.auth.GenerateOAuthAuthorizationUrl( request_token, authorization_url=request_url, callback_url=callback_url, extra_params=extra_params, include_scopes_in_callback=include_scopes_in_callback, scopes_param_prefix=scopes_param_prefix)) def UpgradeToOAuthAccessToken(self, authorized_request_token=None, request_url='%s/accounts/OAuthGetAccessToken' \ % AUTH_SERVER_HOST, oauth_version='1.0'): """Upgrades the authorized request token to an access token. Args: authorized_request_token: gdata.auth.OAuthToken (optional) OAuth request token. If not specified, then the current token will be used if it is of type <gdata.auth.OAuthToken>, else it is found by looking in the token_store by looking for a token for the current scope. oauth_version: str (default='1.0') oauth_version parameter. All other 'oauth_' parameters are added by default. This parameter too, is added by default but here you can override it's value. request_url: Access token URL. The default is 'https://www.google.com/accounts/OAuthGetAccessToken'. Raises: NonOAuthToken if the user's authorized request token is not an OAuth token or if an authorized request token was not available. TokenUpgradeFailed if the server responded to the request with an error. """ if (authorized_request_token and not isinstance(authorized_request_token, gdata.auth.OAuthToken)): raise NonOAuthToken if not authorized_request_token: if isinstance(self.current_token, gdata.auth.OAuthToken): authorized_request_token = self.current_token else: current_scopes = lookup_scopes(self.service) if current_scopes: token = self.token_store.find_token(current_scopes[0]) if isinstance(token, gdata.auth.OAuthToken): authorized_request_token = token if not authorized_request_token: raise NonOAuthToken access_token_url = gdata.auth.GenerateOAuthAccessTokenUrl( authorized_request_token, self._oauth_input_params, access_token_url=request_url, oauth_version=oauth_version) response = self.http_client.request('GET', str(access_token_url)) if response.status == 200: token = gdata.auth.OAuthTokenFromHttpBody(response.read()) token.scopes = authorized_request_token.scopes token.oauth_input_params = authorized_request_token.oauth_input_params self.SetOAuthToken(token) else: raise TokenUpgradeFailed({'status': response.status, 'reason': 'Non 200 response on upgrade', 'body': response.read()}) def RevokeOAuthToken(self, request_url='%s/accounts/AuthSubRevokeToken' % \ AUTH_SERVER_HOST): """Revokes an existing OAuth token. request_url: Token revoke URL. The default is 'https://www.google.com/accounts/AuthSubRevokeToken'. Raises: NonOAuthToken if the user's auth token is not an OAuth token. RevokingOAuthTokenFailed if request for revoking an OAuth token failed. """ scopes = lookup_scopes(self.service) token = self.token_store.find_token(scopes[0]) if not isinstance(token, gdata.auth.OAuthToken): raise NonOAuthToken response = token.perform_request(self.http_client, 'GET', request_url, headers={'Content-Type':'application/x-www-form-urlencoded'}) if response.status == 200: self.token_store.remove_token(token) else: raise RevokingOAuthTokenFailed def GetAuthSubToken(self): """Returns the AuthSub token as a string. If the token is an gdta.auth.AuthSubToken, the Authorization Label ("AuthSub token") is removed. This method examines the current_token to see if it is an AuthSubToken or SecureAuthSubToken. If not, it searches the token_store for a token which matches the current scope. The current scope is determined by the service name string member. Returns: If the current_token is set to an AuthSubToken/SecureAuthSubToken, return the token string. If there is no current_token, a token string for a token which matches the service object's default scope is returned. If there are no tokens valid for the scope, returns None. """ if isinstance(self.current_token, gdata.auth.AuthSubToken): return self.current_token.get_token_string() current_scopes = lookup_scopes(self.service) if current_scopes: token = self.token_store.find_token(current_scopes[0]) if isinstance(token, gdata.auth.AuthSubToken): return token.get_token_string() else: token = self.token_store.find_token(atom.token_store.SCOPE_ALL) if isinstance(token, gdata.auth.ClientLoginToken): return token.get_token_string() return None def SetAuthSubToken(self, token, scopes=None, rsa_key=None): """Sets the token sent in requests to an AuthSub token. Sets the current_token and attempts to add the token to the token_store. Only use this method if you have received a token from the AuthSub service. The auth token is set automatically when UpgradeToSessionToken() is used. See documentation for Google AuthSub here: http://code.google.com/apis/accounts/AuthForWebApps.html Args: token: gdata.auth.AuthSubToken or gdata.auth.SecureAuthSubToken or string The token returned by the AuthSub service. If the token is an AuthSubToken or SecureAuthSubToken, the scope information stored in the token is used. If the token is a string, the scopes parameter is used to determine the valid scopes. scopes: list of URLs for which the token is valid. This is only used if the token parameter is a string. rsa_key: string (optional) Private key required for RSA_SHA1 signature method. This parameter is necessary if the token is a string representing a secure token. """ if not isinstance(token, gdata.auth.AuthSubToken): token_string = token if rsa_key: token = gdata.auth.SecureAuthSubToken(rsa_key) else: token = gdata.auth.AuthSubToken() token.set_token_string(token_string) # If no scopes were set for the token, use the scopes passed in, or # try to determine the scopes based on the current service name. If # all else fails, set the token to match all requests. if not token.scopes: if scopes is None: scopes = lookup_scopes(self.service) if scopes is None: scopes = [atom.token_store.SCOPE_ALL] token.scopes = scopes if self.auto_set_current_token: self.current_token = token if self.auto_store_tokens: self.token_store.add_token(token) def GetClientLoginToken(self): """Returns the token string for the current token or a token matching the service scope. If the current_token is a ClientLoginToken, the token string for the current token is returned. If the current_token is not set, this method searches for a token in the token_store which is valid for the service object's current scope. The current scope is determined by the service name string member. The token string is the end of the Authorization header, it doesn not include the ClientLogin label. """ if isinstance(self.current_token, gdata.auth.ClientLoginToken): return self.current_token.get_token_string() current_scopes = lookup_scopes(self.service) if current_scopes: token = self.token_store.find_token(current_scopes[0]) if isinstance(token, gdata.auth.ClientLoginToken): return token.get_token_string() else: token = self.token_store.find_token(atom.token_store.SCOPE_ALL) if isinstance(token, gdata.auth.ClientLoginToken): return token.get_token_string() return None def SetClientLoginToken(self, token, scopes=None): """Sets the token sent in requests to a ClientLogin token. This method sets the current_token to a new ClientLoginToken and it also attempts to add the ClientLoginToken to the token_store. Only use this method if you have received a token from the ClientLogin service. The auth_token is set automatically when ProgrammaticLogin() is used. See documentation for Google ClientLogin here: http://code.google.com/apis/accounts/docs/AuthForInstalledApps.html Args: token: string or instance of a ClientLoginToken. """ if not isinstance(token, gdata.auth.ClientLoginToken): token_string = token token = gdata.auth.ClientLoginToken() token.set_token_string(token_string) if not token.scopes: if scopes is None: scopes = lookup_scopes(self.service) if scopes is None: scopes = [atom.token_store.SCOPE_ALL] token.scopes = scopes if self.auto_set_current_token: self.current_token = token if self.auto_store_tokens: self.token_store.add_token(token) # Private methods to create the source property. def __GetSource(self): return self.__source def __SetSource(self, new_source): self.__source = new_source # Update the UserAgent header to include the new application name. self.additional_headers['User-Agent'] = atom.http_interface.USER_AGENT % ( self.__source,) source = property(__GetSource, __SetSource, doc="""The source is the name of the application making the request. It should be in the form company_id-app_name-app_version""") # Authentication operations def ProgrammaticLogin(self, captcha_token=None, captcha_response=None): """Authenticates the user and sets the GData Auth token. Login retreives a temporary auth token which must be used with all requests to GData services. The auth token is stored in the GData client object. Login is also used to respond to a captcha challenge. If the user's login attempt failed with a CaptchaRequired error, the user can respond by calling Login with the captcha token and the answer to the challenge. Args: captcha_token: string (optional) The identifier for the captcha challenge which was presented to the user. captcha_response: string (optional) The user's answer to the captch challenge. Raises: CaptchaRequired if the login service will require a captcha response BadAuthentication if the login service rejected the username or password Error if the login service responded with a 403 different from the above """ request_body = gdata.auth.generate_client_login_request_body(self.email, self.password, self.service, self.source, self.account_type, captcha_token, captcha_response) # If the user has defined their own authentication service URL, # send the ClientLogin requests to this URL: if not self.auth_service_url: auth_request_url = AUTH_SERVER_HOST + '/accounts/ClientLogin' else: auth_request_url = self.auth_service_url auth_response = self.http_client.request('POST', auth_request_url, data=request_body, headers={'Content-Type':'application/x-www-form-urlencoded'}) response_body = auth_response.read() if auth_response.status == 200: # TODO: insert the token into the token_store directly. self.SetClientLoginToken( gdata.auth.get_client_login_token(response_body)) self.__captcha_token = None self.__captcha_url = None elif auth_response.status == 403: # Examine each line to find the error type and the captcha token and # captch URL if they are present. captcha_parameters = gdata.auth.get_captcha_challenge(response_body, captcha_base_url='%s/accounts/' % AUTH_SERVER_HOST) if captcha_parameters: self.__captcha_token = captcha_parameters['token'] self.__captcha_url = captcha_parameters['url'] raise CaptchaRequired, 'Captcha Required' elif response_body.splitlines()[0] == 'Error=BadAuthentication': self.__captcha_token = None self.__captcha_url = None raise BadAuthentication, 'Incorrect username or password' else: self.__captcha_token = None self.__captcha_url = None raise Error, 'Server responded with a 403 code' elif auth_response.status == 302: self.__captcha_token = None self.__captcha_url = None # Google tries to redirect all bad URLs back to # http://www.google.<locale>. If a redirect # attempt is made, assume the user has supplied an incorrect authentication URL raise BadAuthenticationServiceURL, 'Server responded with a 302 code.' def ClientLogin(self, username, password, account_type=None, service=None, auth_service_url=None, source=None, captcha_token=None, captcha_response=None): """Convenience method for authenticating using ProgrammaticLogin. Sets values for email, password, and other optional members. Args: username: password: account_type: string (optional) service: string (optional) auth_service_url: string (optional) captcha_token: string (optional) captcha_response: string (optional) """ self.email = username self.password = password if account_type: self.account_type = account_type if service: self.service = service if source: self.source = source if auth_service_url: self.auth_service_url = auth_service_url self.ProgrammaticLogin(captcha_token, captcha_response) def GenerateAuthSubURL(self, next, scope, secure=False, session=True, domain='default'): """Generate a URL at which the user will login and be redirected back. Users enter their credentials on a Google login page and a token is sent to the URL specified in next. See documentation for AuthSub login at: http://code.google.com/apis/accounts/docs/AuthSub.html Args: next: string The URL user will be sent to after logging in. scope: string or list of strings. The URLs of the services to be accessed. secure: boolean (optional) Determines whether or not the issued token is a secure token. session: boolean (optional) Determines whether or not the issued token can be upgraded to a session token. """ if not isinstance(scope, (list, tuple)): scope = (scope,) return gdata.auth.generate_auth_sub_url(next, scope, secure=secure, session=session, request_url='%s/accounts/AuthSubRequest' % AUTH_SERVER_HOST, domain=domain) def UpgradeToSessionToken(self, token=None): """Upgrades a single use AuthSub token to a session token. Args: token: A gdata.auth.AuthSubToken or gdata.auth.SecureAuthSubToken (optional) which is good for a single use but can be upgraded to a session token. If no token is passed in, the token is found by looking in the token_store by looking for a token for the current scope. Raises: NonAuthSubToken if the user's auth token is not an AuthSub token TokenUpgradeFailed if the server responded to the request with an error. """ if token is None: scopes = lookup_scopes(self.service) if scopes: token = self.token_store.find_token(scopes[0]) else: token = self.token_store.find_token(atom.token_store.SCOPE_ALL) if not isinstance(token, gdata.auth.AuthSubToken): raise NonAuthSubToken self.SetAuthSubToken(self.upgrade_to_session_token(token)) def upgrade_to_session_token(self, token): """Upgrades a single use AuthSub token to a session token. Args: token: A gdata.auth.AuthSubToken or gdata.auth.SecureAuthSubToken which is good for a single use but can be upgraded to a session token. Returns: The upgraded token as a gdata.auth.AuthSubToken object. Raises: TokenUpgradeFailed if the server responded to the request with an error. """ response = token.perform_request(self.http_client, 'GET', AUTH_SERVER_HOST + '/accounts/AuthSubSessionToken', headers={'Content-Type':'application/x-www-form-urlencoded'}) response_body = response.read() if response.status == 200: token.set_token_string( gdata.auth.token_from_http_body(response_body)) return token else: raise TokenUpgradeFailed({'status': response.status, 'reason': 'Non 200 response on upgrade', 'body': response_body}) def RevokeAuthSubToken(self): """Revokes an existing AuthSub token. Raises: NonAuthSubToken if the user's auth token is not an AuthSub token """ scopes = lookup_scopes(self.service) token = self.token_store.find_token(scopes[0]) if not isinstance(token, gdata.auth.AuthSubToken): raise NonAuthSubToken response = token.perform_request(self.http_client, 'GET', AUTH_SERVER_HOST + '/accounts/AuthSubRevokeToken', headers={'Content-Type':'application/x-www-form-urlencoded'}) if response.status == 200: self.token_store.remove_token(token) def AuthSubTokenInfo(self): """Fetches the AuthSub token's metadata from the server. Raises: NonAuthSubToken if the user's auth token is not an AuthSub token """ scopes = lookup_scopes(self.service) token = self.token_store.find_token(scopes[0]) if not isinstance(token, gdata.auth.AuthSubToken): raise NonAuthSubToken response = token.perform_request(self.http_client, 'GET', AUTH_SERVER_HOST + '/accounts/AuthSubTokenInfo', headers={'Content-Type':'application/x-www-form-urlencoded'}) result_body = response.read() if response.status == 200: return result_body else: raise RequestError, {'status': response.status, 'body': result_body} # CRUD operations def Get(self, uri, extra_headers=None, redirects_remaining=4, encoding='UTF-8', converter=None): """Query the GData API with the given URI The uri is the portion of the URI after the server value (ex: www.google.com). To perform a query against Google Base, set the server to 'base.google.com' and set the uri to '/base/feeds/...', where ... is your query. For example, to find snippets for all digital cameras uri should be set to: '/base/feeds/snippets?bq=digital+camera' Args: uri: string The query in the form of a URI. Example: '/base/feeds/snippets?bq=digital+camera'. extra_headers: dictionary (optional) Extra HTTP headers to be included in the GET request. These headers are in addition to those stored in the client's additional_headers property. The client automatically sets the Content-Type and Authorization headers. redirects_remaining: int (optional) Tracks the number of additional redirects this method will allow. If the service object receives a redirect and remaining is 0, it will not follow the redirect. This was added to avoid infinite redirect loops. encoding: string (optional) The character encoding for the server's response. Default is UTF-8 converter: func (optional) A function which will transform the server's results before it is returned. Example: use GDataFeedFromString to parse the server response as if it were a GDataFeed. Returns: If there is no ResultsTransformer specified in the call, a GDataFeed or GDataEntry depending on which is sent from the server. If the response is niether a feed or entry and there is no ResultsTransformer, return a string. If there is a ResultsTransformer, the returned value will be that of the ResultsTransformer function. """ if extra_headers is None: extra_headers = {} if self.__gsessionid is not None: if uri.find('gsessionid=') < 0: if uri.find('?') > -1: uri += '&gsessionid=%s' % (self.__gsessionid,) else: uri += '?gsessionid=%s' % (self.__gsessionid,) server_response = self.request('GET', uri, headers=extra_headers) result_body = server_response.read() if server_response.status == 200: if converter: return converter(result_body) # There was no ResultsTransformer specified, so try to convert the # server's response into a GDataFeed. feed = gdata.GDataFeedFromString(result_body) if not feed: # If conversion to a GDataFeed failed, try to convert the server's # response to a GDataEntry. entry = gdata.GDataEntryFromString(result_body) if not entry: # The server's response wasn't a feed, or an entry, so return the # response body as a string. return result_body return entry return feed elif server_response.status == 302: if redirects_remaining > 0: location = server_response.getheader('Location') if location is not None: m = re.compile('[\?\&]gsessionid=(\w*)').search(location) if m is not None: self.__gsessionid = m.group(1) return GDataService.Get(self, location, extra_headers, redirects_remaining - 1, encoding=encoding, converter=converter) else: raise RequestError, {'status': server_response.status, 'reason': '302 received without Location header', 'body': result_body} else: raise RequestError, {'status': server_response.status, 'reason': 'Redirect received, but redirects_remaining <= 0', 'body': result_body} else: raise RequestError, {'status': server_response.status, 'reason': server_response.reason, 'body': result_body} def GetMedia(self, uri, extra_headers=None): """Returns a MediaSource containing media and its metadata from the given URI string. """ response_handle = self.request('GET', uri, headers=extra_headers) return gdata.MediaSource(response_handle, response_handle.getheader( 'Content-Type'), response_handle.getheader('Content-Length')) def GetEntry(self, uri, extra_headers=None): """Query the GData API with the given URI and receive an Entry. See also documentation for gdata.service.Get Args: uri: string The query in the form of a URI. Example: '/base/feeds/snippets?bq=digital+camera'. extra_headers: dictionary (optional) Extra HTTP headers to be included in the GET request. These headers are in addition to those stored in the client's additional_headers property. The client automatically sets the Content-Type and Authorization headers. Returns: A GDataEntry built from the XML in the server's response. """ result = GDataService.Get(self, uri, extra_headers, converter=atom.EntryFromString) if isinstance(result, atom.Entry): return result else: raise UnexpectedReturnType, 'Server did not send an entry' def GetFeed(self, uri, extra_headers=None, converter=gdata.GDataFeedFromString): """Query the GData API with the given URI and receive a Feed. See also documentation for gdata.service.Get Args: uri: string The query in the form of a URI. Example: '/base/feeds/snippets?bq=digital+camera'. extra_headers: dictionary (optional) Extra HTTP headers to be included in the GET request. These headers are in addition to those stored in the client's additional_headers property. The client automatically sets the Content-Type and Authorization headers. Returns: A GDataFeed built from the XML in the server's response. """ result = GDataService.Get(self, uri, extra_headers, converter=converter) if isinstance(result, atom.Feed): return result else: raise UnexpectedReturnType, 'Server did not send a feed' def GetNext(self, feed): """Requests the next 'page' of results in the feed. This method uses the feed's next link to request an additional feed and uses the class of the feed to convert the results of the GET request. Args: feed: atom.Feed or a subclass. The feed should contain a next link and the type of the feed will be applied to the results from the server. The new feed which is returned will be of the same class as this feed which was passed in. Returns: A new feed representing the next set of results in the server's feed. The type of this feed will match that of the feed argument. """ next_link = feed.GetNextLink() # Create a closure which will convert an XML string to the class of # the feed object passed in. def ConvertToFeedClass(xml_string): return atom.CreateClassFromXMLString(feed.__class__, xml_string) # Make a GET request on the next link and use the above closure for the # converted which processes the XML string from the server. if next_link and next_link.href: return GDataService.Get(self, next_link.href, converter=ConvertToFeedClass) else: return None def Post(self, data, uri, extra_headers=None, url_params=None, escape_params=True, redirects_remaining=4, media_source=None, converter=None): """Insert or update data into a GData service at the given URI. Args: data: string, ElementTree._Element, atom.Entry, or gdata.GDataEntry The XML to be sent to the uri. uri: string The location (feed) to which the data should be inserted. Example: '/base/feeds/items'. extra_headers: dict (optional) HTTP headers which are to be included. The client automatically sets the Content-Type, Authorization, and Content-Length headers. url_params: dict (optional) Additional URL parameters to be included in the URI. These are translated into query arguments in the form '&dict_key=value&...'. Example: {'max-results': '250'} becomes &max-results=250 escape_params: boolean (optional) If false, the calling code has already ensured that the query will form a valid URL (all reserved characters have been escaped). If true, this method will escape the query and any URL parameters provided. media_source: MediaSource (optional) Container for the media to be sent along with the entry, if provided. converter: func (optional) A function which will be executed on the server's response. Often this is a function like GDataEntryFromString which will parse the body of the server's response and return a GDataEntry. Returns: If the post succeeded, this method will return a GDataFeed, GDataEntry, or the results of running converter on the server's result body (if converter was specified). """ return GDataService.PostOrPut(self, 'POST', data, uri, extra_headers=extra_headers, url_params=url_params, escape_params=escape_params, redirects_remaining=redirects_remaining, media_source=media_source, converter=converter) def PostOrPut(self, verb, data, uri, extra_headers=None, url_params=None, escape_params=True, redirects_remaining=4, media_source=None, converter=None): """Insert data into a GData service at the given URI. Args: verb: string, either 'POST' or 'PUT' data: string, ElementTree._Element, atom.Entry, or gdata.GDataEntry The XML to be sent to the uri. uri: string The location (feed) to which the data should be inserted. Example: '/base/feeds/items'. extra_headers: dict (optional) HTTP headers which are to be included. The client automatically sets the Content-Type, Authorization, and Content-Length headers. url_params: dict (optional) Additional URL parameters to be included in the URI. These are translated into query arguments in the form '&dict_key=value&...'. Example: {'max-results': '250'} becomes &max-results=250 escape_params: boolean (optional) If false, the calling code has already ensured that the query will form a valid URL (all reserved characters have been escaped). If true, this method will escape the query and any URL parameters provided. media_source: MediaSource (optional) Container for the media to be sent along with the entry, if provided. converter: func (optional) A function which will be executed on the server's response. Often this is a function like GDataEntryFromString which will parse the body of the server's response and return a GDataEntry. Returns: If the post succeeded, this method will return a GDataFeed, GDataEntry, or the results of running converter on the server's result body (if converter was specified). """ if extra_headers is None: extra_headers = {} if self.__gsessionid is not None: if uri.find('gsessionid=') < 0: if uri.find('?') > -1: uri += '&gsessionid=%s' % (self.__gsessionid,) else: uri += '?gsessionid=%s' % (self.__gsessionid,) if data and media_source: if ElementTree.iselement(data): data_str = ElementTree.tostring(data) else: data_str = str(data) multipart = [] multipart.append('Media multipart posting\r\n--END_OF_PART\r\n' + \ 'Content-Type: application/atom+xml\r\n\r\n') multipart.append('\r\n--END_OF_PART\r\nContent-Type: ' + \ media_source.content_type+'\r\n\r\n') multipart.append('\r\n--END_OF_PART--\r\n') extra_headers['MIME-version'] = '1.0' extra_headers['Content-Length'] = str(len(multipart[0]) + len(multipart[1]) + len(multipart[2]) + len(data_str) + media_source.content_length) extra_headers['Content-Type'] = 'multipart/related; boundary=END_OF_PART' server_response = self.request(verb, uri, data=[multipart[0], data_str, multipart[1], media_source.file_handle, multipart[2]], headers=extra_headers) result_body = server_response.read() elif media_source or isinstance(data, gdata.MediaSource): if isinstance(data, gdata.MediaSource): media_source = data extra_headers['Content-Length'] = str(media_source.content_length) extra_headers['Content-Type'] = media_source.content_type server_response = self.request(verb, uri, data=media_source.file_handle, headers=extra_headers) result_body = server_response.read() else: http_data = data content_type = 'application/atom+xml' extra_headers['Content-Type'] = content_type server_response = self.request(verb, uri, data=http_data, headers=extra_headers) result_body = server_response.read() # Server returns 201 for most post requests, but when performing a batch # request the server responds with a 200 on success. if server_response.status == 201 or server_response.status == 200: if converter: return converter(result_body) feed = gdata.GDataFeedFromString(result_body) if not feed: entry = gdata.GDataEntryFromString(result_body) if not entry: return result_body return entry return feed elif server_response.status == 302: if redirects_remaining > 0: location = server_response.getheader('Location') if location is not None: m = re.compile('[\?\&]gsessionid=(\w*)').search(location) if m is not None: self.__gsessionid = m.group(1) return GDataService.PostOrPut(self, verb, data, location, extra_headers, url_params, escape_params, redirects_remaining - 1, media_source, converter=converter) else: raise RequestError, {'status': server_response.status, 'reason': '302 received without Location header', 'body': result_body} else: raise RequestError, {'status': server_response.status, 'reason': 'Redirect received, but redirects_remaining <= 0', 'body': result_body} else: raise RequestError, {'status': server_response.status, 'reason': server_response.reason, 'body': result_body} def Put(self, data, uri, extra_headers=None, url_params=None, escape_params=True, redirects_remaining=3, media_source=None, converter=None): """Updates an entry at the given URI. Args: data: string, ElementTree._Element, or xml_wrapper.ElementWrapper The XML containing the updated data. uri: string A URI indicating entry to which the update will be applied. Example: '/base/feeds/items/ITEM-ID' extra_headers: dict (optional) HTTP headers which are to be included. The client automatically sets the Content-Type, Authorization, and Content-Length headers. url_params: dict (optional) Additional URL parameters to be included in the URI. These are translated into query arguments in the form '&dict_key=value&...'. Example: {'max-results': '250'} becomes &max-results=250 escape_params: boolean (optional) If false, the calling code has already ensured that the query will form a valid URL (all reserved characters have been escaped). If true, this method will escape the query and any URL parameters provided. converter: func (optional) A function which will be executed on the server's response. Often this is a function like GDataEntryFromString which will parse the body of the server's response and return a GDataEntry. Returns: If the put succeeded, this method will return a GDataFeed, GDataEntry, or the results of running converter on the server's result body (if converter was specified). """ return GDataService.PostOrPut(self, 'PUT', data, uri, extra_headers=extra_headers, url_params=url_params, escape_params=escape_params, redirects_remaining=redirects_remaining, media_source=media_source, converter=converter) def Delete(self, uri, extra_headers=None, url_params=None, escape_params=True, redirects_remaining=4): """Deletes the entry at the given URI. Args: uri: string The URI of the entry to be deleted. Example: '/base/feeds/items/ITEM-ID' extra_headers: dict (optional) HTTP headers which are to be included. The client automatically sets the Content-Type and Authorization headers. url_params: dict (optional) Additional URL parameters to be included in the URI. These are translated into query arguments in the form '&dict_key=value&...'. Example: {'max-results': '250'} becomes &max-results=250 escape_params: boolean (optional) If false, the calling code has already ensured that the query will form a valid URL (all reserved characters have been escaped). If true, this method will escape the query and any URL parameters provided. Returns: True if the entry was deleted. """ if extra_headers is None: extra_headers = {} if self.__gsessionid is not None: if uri.find('gsessionid=') < 0: if uri.find('?') > -1: uri += '&gsessionid=%s' % (self.__gsessionid,) else: uri += '?gsessionid=%s' % (self.__gsessionid,) server_response = self.request('DELETE', uri, headers=extra_headers) result_body = server_response.read() if server_response.status == 200: return True elif server_response.status == 302: if redirects_remaining > 0: location = server_response.getheader('Location') if location is not None: m = re.compile('[\?\&]gsessionid=(\w*)').search(location) if m is not None: self.__gsessionid = m.group(1) return GDataService.Delete(self, location, extra_headers, url_params, escape_params, redirects_remaining - 1) else: raise RequestError, {'status': server_response.status, 'reason': '302 received without Location header', 'body': result_body} else: raise RequestError, {'status': server_response.status, 'reason': 'Redirect received, but redirects_remaining <= 0', 'body': result_body} else: raise RequestError, {'status': server_response.status, 'reason': server_response.reason, 'body': result_body} def ExtractToken(url, scopes_included_in_next=True): """Gets the AuthSub token from the current page's URL. Designed to be used on the URL that the browser is sent to after the user authorizes this application at the page given by GenerateAuthSubRequestUrl. Args: url: The current page's URL. It should contain the token as a URL parameter. Example: 'http://example.com/?...&token=abcd435' scopes_included_in_next: If True, this function looks for a scope value associated with the token. The scope is a URL parameter with the key set to SCOPE_URL_PARAM_NAME. This parameter should be present if the AuthSub request URL was generated using GenerateAuthSubRequestUrl with include_scope_in_next set to True. Returns: A tuple containing the token string and a list of scope strings for which this token should be valid. If the scope was not included in the URL, the tuple will contain (token, None). """ parsed = urlparse.urlparse(url) token = gdata.auth.AuthSubTokenFromUrl(parsed[4]) scopes = '' if scopes_included_in_next: for pair in parsed[4].split('&'): if pair.startswith('%s=' % SCOPE_URL_PARAM_NAME): scopes = urllib.unquote_plus(pair.split('=')[1]) return (token, scopes.split(' ')) def GenerateAuthSubRequestUrl(next, scopes, hd='default', secure=False, session=True, request_url='http://www.google.com/accounts/AuthSubRequest', include_scopes_in_next=True): """Creates a URL to request an AuthSub token to access Google services. For more details on AuthSub, see the documentation here: http://code.google.com/apis/accounts/docs/AuthSub.html Args: next: The URL where the browser should be sent after the user authorizes the application. This page is responsible for receiving the token which is embeded in the URL as a parameter. scopes: The base URL to which access will be granted. Example: 'http://www.google.com/calendar/feeds' will grant access to all URLs in the Google Calendar data API. If you would like a token for multiple scopes, pass in a list of URL strings. hd: The domain to which the user's account belongs. This is set to the domain name if you are using Google Apps. Example: 'example.org' Defaults to 'default' secure: If set to True, all requests should be signed. The default is False. session: If set to True, the token received by the 'next' URL can be upgraded to a multiuse session token. If session is set to False, the token may only be used once and cannot be upgraded. Default is True. request_url: The base of the URL to which the user will be sent to authorize this application to access their data. The default is 'http://www.google.com/accounts/AuthSubRequest'. include_scopes_in_next: Boolean if set to true, the 'next' parameter will be modified to include the requested scope as a URL parameter. The key for the next's scope parameter will be SCOPE_URL_PARAM_NAME. The benefit of including the scope URL as a parameter to the next URL, is that the page which receives the AuthSub token will be able to tell which URLs the token grants access to. Returns: A URL string to which the browser should be sent. """ if isinstance(scopes, list): scope = ' '.join(scopes) else: scope = scopes if include_scopes_in_next: if next.find('?') > -1: next += '&%s' % urllib.urlencode({SCOPE_URL_PARAM_NAME:scope}) else: next += '?%s' % urllib.urlencode({SCOPE_URL_PARAM_NAME:scope}) return gdata.auth.GenerateAuthSubUrl(next=next, scope=scope, secure=secure, session=session, request_url=request_url, domain=hd) class Query(dict): """Constructs a query URL to be used in GET requests Url parameters are created by adding key-value pairs to this object as a dict. For example, to add &max-results=25 to the URL do my_query['max-results'] = 25 Category queries are created by adding category strings to the categories member. All items in the categories list will be concatenated with the / symbol (symbolizing a category x AND y restriction). If you would like to OR 2 categories, append them as one string with a | between the categories. For example, do query.categories.append('Fritz|Laurie') to create a query like this feed/-/Fritz%7CLaurie . This query will look for results in both categories. """ def __init__(self, feed=None, text_query=None, params=None, categories=None): """Constructor for Query Args: feed: str (optional) The path for the feed (Examples: '/base/feeds/snippets' or 'calendar/feeds/jo@gmail.com/private/full' text_query: str (optional) The contents of the q query parameter. The contents of the text_query are URL escaped upon conversion to a URI. params: dict (optional) Parameter value string pairs which become URL params when translated to a URI. These parameters are added to the query's items (key-value pairs). categories: list (optional) List of category strings which should be included as query categories. See http://code.google.com/apis/gdata/reference.html#Queries for details. If you want to get results from category A or B (both categories), specify a single list item 'A|B'. """ self.feed = feed self.categories = [] if text_query: self.text_query = text_query if isinstance(params, dict): for param in params: self[param] = params[param] if isinstance(categories, list): for category in categories: self.categories.append(category) def _GetTextQuery(self): if 'q' in self.keys(): return self['q'] else: return None def _SetTextQuery(self, query): self['q'] = query text_query = property(_GetTextQuery, _SetTextQuery, doc="""The feed query's q parameter""") def _GetAuthor(self): if 'author' in self.keys(): return self['author'] else: return None def _SetAuthor(self, query): self['author'] = query author = property(_GetAuthor, _SetAuthor, doc="""The feed query's author parameter""") def _GetAlt(self): if 'alt' in self.keys(): return self['alt'] else: return None def _SetAlt(self, query): self['alt'] = query alt = property(_GetAlt, _SetAlt, doc="""The feed query's alt parameter""") def _GetUpdatedMin(self): if 'updated-min' in self.keys(): return self['updated-min'] else: return None def _SetUpdatedMin(self, query): self['updated-min'] = query updated_min = property(_GetUpdatedMin, _SetUpdatedMin, doc="""The feed query's updated-min parameter""") def _GetUpdatedMax(self): if 'updated-max' in self.keys(): return self['updated-max'] else: return None def _SetUpdatedMax(self, query): self['updated-max'] = query updated_max = property(_GetUpdatedMax, _SetUpdatedMax, doc="""The feed query's updated-max parameter""") def _GetPublishedMin(self): if 'published-min' in self.keys(): return self['published-min'] else: return None def _SetPublishedMin(self, query): self['published-min'] = query published_min = property(_GetPublishedMin, _SetPublishedMin, doc="""The feed query's published-min parameter""") def _GetPublishedMax(self): if 'published-max' in self.keys(): return self['published-max'] else: return None def _SetPublishedMax(self, query): self['published-max'] = query published_max = property(_GetPublishedMax, _SetPublishedMax, doc="""The feed query's published-max parameter""") def _GetStartIndex(self): if 'start-index' in self.keys(): return self['start-index'] else: return None def _SetStartIndex(self, query): if not isinstance(query, str): query = str(query) self['start-index'] = query start_index = property(_GetStartIndex, _SetStartIndex, doc="""The feed query's start-index parameter""") def _GetMaxResults(self): if 'max-results' in self.keys(): return self['max-results'] else: return None def _SetMaxResults(self, query): if not isinstance(query, str): query = str(query) self['max-results'] = query max_results = property(_GetMaxResults, _SetMaxResults, doc="""The feed query's max-results parameter""") def _GetOrderBy(self): if 'orderby' in self.keys(): return self['orderby'] else: return None def _SetOrderBy(self, query): self['orderby'] = query orderby = property(_GetOrderBy, _SetOrderBy, doc="""The feed query's orderby parameter""") def ToUri(self): q_feed = self.feed or '' category_string = '/'.join( [urllib.quote_plus(c) for c in self.categories]) # Add categories to the feed if there are any. if len(self.categories) > 0: q_feed = q_feed + '/-/' + category_string return atom.service.BuildUri(q_feed, self) def __str__(self): return self.ToUri()