#!/usr/bin/env python # # Copyright 2007 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. # """Tool for performing authenticated RPCs against App Engine.""" import google import cookielib import cStringIO import fancy_urllib import gzip import hashlib import logging import os import re import socket import sys import time import urllib import urllib2 logger = logging.getLogger('google.appengine.tools.appengine_rpc') def GetPlatformToken(os_module=os, sys_module=sys, platform=sys.platform): """Returns a 'User-agent' token for the host system platform. Args: os_module, sys_module, platform: Used for testing. Returns: String containing the platform token for the host system. """ if hasattr(sys_module, "getwindowsversion"): windows_version = sys_module.getwindowsversion() version_info = ".".join(str(i) for i in windows_version[:4]) return platform + "/" + version_info elif hasattr(os_module, "uname"): uname = os_module.uname() return "%s/%s" % (uname[0], uname[2]) else: return "unknown" def HttpRequestToString(req, include_data=True): """Converts a urllib2.Request to a string. Args: req: urllib2.Request Returns: Multi-line string representing the request. """ headers = "" for header in req.header_items(): headers += "%s: %s\n" % (header[0], header[1]) template = ("%(method)s %(selector)s %(type)s/1.1\n" "Host: %(host)s\n" "%(headers)s") if include_data: template = template + "\n%(data)s" return template % { 'method': req.get_method(), 'selector': req.get_selector(), 'type': req.get_type().upper(), 'host': req.get_host(), 'headers': headers, 'data': req.get_data(), } class ClientLoginError(urllib2.HTTPError): """Raised to indicate there was an error authenticating with ClientLogin.""" def __init__(self, url, code, msg, headers, args): urllib2.HTTPError.__init__(self, url, code, msg, headers, None) self.args = args self._reason = args.get("Error") self.info = args.get("Info") def read(self): return '%d %s: %s' % (self.code, self.msg, self.reason) @property def reason(self): return self._reason class AbstractRpcServer(object): """Provides a common interface for a simple RPC server.""" RUNTIME = "python" def __init__(self, host, auth_function, user_agent, source, host_override=None, extra_headers=None, save_cookies=False, auth_tries=3, account_type=None, debug_data=True, secure=True, ignore_certs=False, rpc_tries=3, options=None): """Creates a new HttpRpcServer. Args: host: The host to send requests to. auth_function: A function that takes no arguments and returns an (email, password) tuple when called. Will be called if authentication is required. user_agent: The user-agent string to send to the server. Specify None to omit the user-agent header. source: The source to specify in authentication requests. host_override: The host header to send to the server (defaults to host). extra_headers: A dict of extra headers to append to every request. Values supplied here will override other default headers that are supplied. save_cookies: If True, save the authentication cookies to local disk. If False, use an in-memory cookiejar instead. Subclasses must implement this functionality. Defaults to False. auth_tries: The number of times to attempt auth_function before failing. account_type: One of GOOGLE, HOSTED_OR_GOOGLE, or None for automatic. debug_data: Whether debugging output should include data contents. secure: If the requests sent using Send should be sent over HTTPS. ignore_certs: If the certificate mismatches should be ignored. rpc_tries: The number of rpc retries upon http server error (i.e. Response code >= 500 and < 600) before failing. options: the command line options (ignored in this implementation). """ if secure: self.scheme = "https" else: self.scheme = "http" self.ignore_certs = ignore_certs self.host = host self.host_override = host_override self.auth_function = auth_function self.source = source self.authenticated = False self.auth_tries = auth_tries self.debug_data = debug_data self.rpc_tries = rpc_tries self.account_type = account_type self.extra_headers = {} if user_agent: self.extra_headers["User-Agent"] = user_agent if extra_headers: self.extra_headers.update(extra_headers) self.save_cookies = save_cookies self.cookie_jar = cookielib.MozillaCookieJar() self.opener = self._GetOpener() if self.host_override: logger.debug("Server: %s; Host: %s", self.host, self.host_override) else: logger.debug("Server: %s", self.host) if ((self.host_override and self.host_override == "localhost") or self.host == "localhost" or self.host.startswith("localhost:")): self._DevAppServerAuthenticate() def _GetOpener(self): """Returns an OpenerDirector for making HTTP requests. Returns: A urllib2.OpenerDirector object. """ raise NotImplementedError def _CreateRequest(self, url, data=None): """Creates a new urllib request.""" req = fancy_urllib.FancyRequest(url, data=data) if self.host_override: req.add_header("Host", self.host_override) for key, value in self.extra_headers.iteritems(): req.add_header(key, value) return req def _GetAuthToken(self, email, password): """Uses ClientLogin to authenticate the user, returning an auth token. Args: email: The user's email address password: The user's password Raises: ClientLoginError: If there was an error authenticating with ClientLogin. HTTPError: If there was some other form of HTTP error. Returns: The authentication token returned by ClientLogin. """ account_type = self.account_type if not account_type: if (self.host.split(':')[0].endswith(".google.com") or (self.host_override and self.host_override.split(':')[0].endswith(".google.com"))): account_type = "HOSTED_OR_GOOGLE" else: account_type = "GOOGLE" data = { "Email": email, "Passwd": password, "service": "ah", "source": self.source, "accountType": account_type } req = self._CreateRequest( url=("https://%s/accounts/ClientLogin" % os.getenv("APPENGINE_AUTH_SERVER", "www.google.com")), data=urllib.urlencode(data)) try: response = self.opener.open(req) response_body = response.read() response_dict = dict(x.split("=") for x in response_body.split("\n") if x) if os.getenv("APPENGINE_RPC_USE_SID", "0") == "1": self.extra_headers["Cookie"] = ( 'SID=%s; Path=/;' % response_dict["SID"]) return response_dict["Auth"] except urllib2.HTTPError, e: if e.code == 403: body = e.read() response_dict = dict(x.split("=", 1) for x in body.split("\n") if x) raise ClientLoginError(req.get_full_url(), e.code, e.msg, e.headers, response_dict) else: raise def _GetAuthCookie(self, auth_token): """Fetches authentication cookies for an authentication token. Args: auth_token: The authentication token returned by ClientLogin. Raises: HTTPError: If there was an error fetching the authentication cookies. """ continue_location = "http://localhost/" args = {"continue": continue_location, "auth": auth_token} login_path = os.environ.get("APPCFG_LOGIN_PATH", "/_ah") req = self._CreateRequest("%s://%s%s/login?%s" % (self.scheme, self.host, login_path, urllib.urlencode(args))) try: response = self.opener.open(req) except urllib2.HTTPError, e: response = e if (response.code != 302 or response.info()["location"] != continue_location): raise urllib2.HTTPError(req.get_full_url(), response.code, response.msg, response.headers, response.fp) self.authenticated = True def _Authenticate(self): """Authenticates the user. The authentication process works as follows: 1) We get a username and password from the user 2) We use ClientLogin to obtain an AUTH token for the user (see http://code.google.com/apis/accounts/AuthForInstalledApps.html). 3) We pass the auth token to /_ah/login on the server to obtain an authentication cookie. If login was successful, it tries to redirect us to the URL we provided. If we attempt to access the upload API without first obtaining an authentication cookie, it returns a 401 response and directs us to authenticate ourselves with ClientLogin. """ for unused_i in range(self.auth_tries): credentials = self.auth_function() try: auth_token = self._GetAuthToken(credentials[0], credentials[1]) if os.getenv("APPENGINE_RPC_USE_SID", "0") == "1": return except ClientLoginError, e: if e.reason == "CaptchaRequired": print >>sys.stderr, ( "Please go to\n" "https://www.google.com/accounts/DisplayUnlockCaptcha\n" "and verify you are a human. Then try again.") break if e.reason == "NotVerified": print >>sys.stderr, "Account not verified." break if e.reason == "TermsNotAgreed": print >>sys.stderr, "User has not agreed to TOS." break if e.reason == "AccountDeleted": print >>sys.stderr, "The user account has been deleted." break if e.reason == "AccountDisabled": print >>sys.stderr, "The user account has been disabled." break if e.reason == "ServiceDisabled": print >>sys.stderr, ("The user's access to the service has been " "disabled.") break if e.reason == "ServiceUnavailable": print >>sys.stderr, "The service is not available; try again later." break raise self._GetAuthCookie(auth_token) return @staticmethod def _CreateDevAppServerCookieData(email, admin): """Creates cookie payload data. Args: email: The user's email address. admin: True if the user is an admin; False otherwise. Returns: String containing the cookie payload. """ if email: user_id_digest = hashlib.md5(email.lower()).digest() user_id = "1" + "".join(["%02d" % ord(x) for x in user_id_digest])[:20] else: user_id = "" return "%s:%s:%s" % (email, bool(admin), user_id) def _DevAppServerAuthenticate(self): """Authenticates the user on the dev_appserver.""" credentials = self.auth_function() value = self._CreateDevAppServerCookieData(credentials[0], True) self.extra_headers["Cookie"] = ('dev_appserver_login="%s"; Path=/;' % value) def Send(self, request_path, payload="", content_type="application/octet-stream", timeout=None, **kwargs): """Sends an RPC and returns the response. Args: request_path: The path to send the request to, eg /api/appversion/create. payload: The body of the request, or None to send an empty request. content_type: The Content-Type header to use. timeout: timeout in seconds; default None i.e. no timeout. (Note: for large requests on OS X, the timeout doesn't work right.) kwargs: Any keyword arguments are converted into query string parameters. Returns: The response body, as a string. """ old_timeout = socket.getdefaulttimeout() socket.setdefaulttimeout(timeout) try: tries = 0 auth_tried = False while True: tries += 1 url = "%s://%s%s" % (self.scheme, self.host, request_path) if kwargs: url += "?" + urllib.urlencode(sorted(kwargs.items())) req = self._CreateRequest(url=url, data=payload) req.add_header("Content-Type", content_type) req.add_header("X-appcfg-api-version", "1") try: logger.debug('Sending %s request:\n%s', self.scheme.upper(), HttpRequestToString(req, include_data=self.debug_data)) f = self.opener.open(req) response = f.read() f.close() return response except urllib2.HTTPError, e: logger.debug("Got http error, this is try #%s", tries) if tries > self.rpc_tries: raise elif e.code == 401: if auth_tried: raise auth_tried = True self._Authenticate() elif e.code >= 500 and e.code < 600: continue elif e.code == 302: if auth_tried: raise auth_tried = True loc = e.info()["location"] logger.debug("Got 302 redirect. Location: %s", loc) if loc.startswith("https://www.google.com/accounts/ServiceLogin"): self._Authenticate() elif re.match( r"https://www\.google\.com/a/[a-z0-9\.\-]+/ServiceLogin", loc): self.account_type = os.getenv("APPENGINE_RPC_HOSTED_LOGIN_TYPE", "HOSTED") self._Authenticate() elif loc.startswith("http://%s/_ah/login" % (self.host,)): self._DevAppServerAuthenticate() else: raise else: raise finally: socket.setdefaulttimeout(old_timeout) class ContentEncodingHandler(urllib2.BaseHandler): """Request and handle HTTP Content-Encoding.""" def http_request(self, request): request.add_header("Accept-Encoding", "gzip") for header in request.headers: if header.lower() == "user-agent": request.headers[header] += " gzip" return request https_request = http_request def http_response(self, req, resp): """Handle encodings in the order that they are encountered.""" encodings = [] headers = resp.headers encoding_header = None for header in headers: if header.lower() == "content-encoding": encoding_header = header for encoding in headers[header].split(","): encoding = encoding.strip() if encoding: encodings.append(encoding) break if not encodings: return resp del headers[encoding_header] fp = resp while encodings and encodings[-1].lower() == "gzip": fp = cStringIO.StringIO(fp.read()) fp = gzip.GzipFile(fileobj=fp, mode="r") encodings.pop() if encodings: headers[encoding_header] = ", ".join(encodings) logger.warning("Unrecognized Content-Encoding: %s", encodings[-1]) msg = resp.msg if sys.version_info >= (2, 6): resp = urllib2.addinfourl(fp, headers, resp.url, resp.code) else: response_code = resp.code resp = urllib2.addinfourl(fp, headers, resp.url) resp.code = response_code resp.msg = msg return resp https_response = http_response class HttpRpcServer(AbstractRpcServer): """Provides a simplified RPC-style interface for HTTP requests.""" DEFAULT_COOKIE_FILE_PATH = "~/.appcfg_cookies" def __init__(self, *args, **kwargs): self.certpath = os.path.normpath(os.path.join( os.path.dirname(__file__), '..', '..', '..', 'lib', 'cacerts', 'cacerts.txt')) self.cert_file_available = ((not kwargs.get("ignore_certs", False)) and os.path.exists(self.certpath)) super(HttpRpcServer, self).__init__(*args, **kwargs) def _CreateRequest(self, url, data=None): """Creates a new urllib request.""" req = super(HttpRpcServer, self)._CreateRequest(url, data) if self.cert_file_available and fancy_urllib.can_validate_certs(): req.set_ssl_info(ca_certs=self.certpath) return req def _CheckCookie(self): """Warn if cookie is not valid for at least one minute.""" min_expire = time.time() + 60 for cookie in self.cookie_jar: if cookie.domain == self.host and not cookie.is_expired(min_expire): break else: print >>sys.stderr, "\nError: Machine system clock is incorrect.\n" def _Authenticate(self): """Save the cookie jar after authentication.""" if self.cert_file_available and not fancy_urllib.can_validate_certs(): logger.warn("""ssl module not found. Without the ssl module, the identity of the remote host cannot be verified, and connections may NOT be secure. To fix this, please install the ssl module from http://pypi.python.org/pypi/ssl . To learn more, see https://developers.google.com/appengine/kb/general#rpcssl""") super(HttpRpcServer, self)._Authenticate() if self.cookie_jar.filename is not None and self.save_cookies: logger.debug("Saving authentication cookies to %s", self.cookie_jar.filename) self.cookie_jar.save() self._CheckCookie() def _GetOpener(self): """Returns an OpenerDirector that supports cookies and ignores redirects. Returns: A urllib2.OpenerDirector object. """ opener = urllib2.OpenerDirector() opener.add_handler(fancy_urllib.FancyProxyHandler()) opener.add_handler(urllib2.UnknownHandler()) opener.add_handler(urllib2.HTTPHandler()) opener.add_handler(urllib2.HTTPDefaultErrorHandler()) opener.add_handler(fancy_urllib.FancyHTTPSHandler()) opener.add_handler(urllib2.HTTPErrorProcessor()) opener.add_handler(ContentEncodingHandler()) if self.save_cookies: self.cookie_jar.filename = os.path.expanduser( HttpRpcServer.DEFAULT_COOKIE_FILE_PATH) if os.path.exists(self.cookie_jar.filename): try: self.cookie_jar.load() self.authenticated = True logger.debug("Loaded authentication cookies from %s", self.cookie_jar.filename) except (OSError, IOError, cookielib.LoadError), e: logger.debug("Could not load authentication cookies; %s: %s", e.__class__.__name__, e) self.cookie_jar.filename = None else: try: fd = os.open(self.cookie_jar.filename, os.O_CREAT, 0600) os.close(fd) except (OSError, IOError), e: logger.debug("Could not create authentication cookies file; %s: %s", e.__class__.__name__, e) self.cookie_jar.filename = None opener.add_handler(urllib2.HTTPCookieProcessor(self.cookie_jar)) return opener