# Copyright 2008 Google Inc. All Rights Reserved. # Code originally from Ian Bicking # (http://code.google.com/p/appengine-monkey/). # Contributed by Ian and subsequently modified here at Google. """Copyright 2008 Python Software Foundation, Ian Bicking, and Google.""" import cStringIO import inspect import mimetools HTTP_PORT = 80 HTTPS_PORT = 443 _UNKNOWN = 'UNKNOWN' # status codes # informational CONTINUE = 100 SWITCHING_PROTOCOLS = 101 PROCESSING = 102 # successful OK = 200 CREATED = 201 ACCEPTED = 202 NON_AUTHORITATIVE_INFORMATION = 203 NO_CONTENT = 204 RESET_CONTENT = 205 PARTIAL_CONTENT = 206 MULTI_STATUS = 207 IM_USED = 226 # redirection MULTIPLE_CHOICES = 300 MOVED_PERMANENTLY = 301 FOUND = 302 SEE_OTHER = 303 NOT_MODIFIED = 304 USE_PROXY = 305 TEMPORARY_REDIRECT = 307 # client error BAD_REQUEST = 400 UNAUTHORIZED = 401 PAYMENT_REQUIRED = 402 FORBIDDEN = 403 NOT_FOUND = 404 METHOD_NOT_ALLOWED = 405 NOT_ACCEPTABLE = 406 PROXY_AUTHENTICATION_REQUIRED = 407 REQUEST_TIMEOUT = 408 CONFLICT = 409 GONE = 410 LENGTH_REQUIRED = 411 PRECONDITION_FAILED = 412 REQUEST_ENTITY_TOO_LARGE = 413 REQUEST_URI_TOO_LONG = 414 UNSUPPORTED_MEDIA_TYPE = 415 REQUESTED_RANGE_NOT_SATISFIABLE = 416 EXPECTATION_FAILED = 417 UNPROCESSABLE_ENTITY = 422 LOCKED = 423 FAILED_DEPENDENCY = 424 UPGRADE_REQUIRED = 426 # server error INTERNAL_SERVER_ERROR = 500 NOT_IMPLEMENTED = 501 BAD_GATEWAY = 502 SERVICE_UNAVAILABLE = 503 GATEWAY_TIMEOUT = 504 HTTP_VERSION_NOT_SUPPORTED = 505 INSUFFICIENT_STORAGE = 507 NOT_EXTENDED = 510 # Mapping status codes to official W3C names responses = { 100: 'Continue', 101: 'Switching Protocols', 200: 'OK', 201: 'Created', 202: 'Accepted', 203: 'Non-Authoritative Information', 204: 'No Content', 205: 'Reset Content', 206: 'Partial Content', 300: 'Multiple Choices', 301: 'Moved Permanently', 302: 'Found', 303: 'See Other', 304: 'Not Modified', 305: 'Use Proxy', 306: '(Unused)', 307: 'Temporary Redirect', 400: 'Bad Request', 401: 'Unauthorized', 402: 'Payment Required', 403: 'Forbidden', 404: 'Not Found', 405: 'Method Not Allowed', 406: 'Not Acceptable', 407: 'Proxy Authentication Required', 408: 'Request Timeout', 409: 'Conflict', 410: 'Gone', 411: 'Length Required', 412: 'Precondition Failed', 413: 'Request Entity Too Large', 414: 'Request-URI Too Long', 415: 'Unsupported Media Type', 416: 'Requested Range Not Satisfiable', 417: 'Expectation Failed', 500: 'Internal Server Error', 501: 'Not Implemented', 502: 'Bad Gateway', 503: 'Service Unavailable', 504: 'Gateway Timeout', 505: 'HTTP Version Not Supported', } # maximal amount of data to read at one time in _safe_read MAXAMOUNT = 1048576 # maximal line length when calling readline(). _MAXLINE = 65536 # Can't get this symbol from socket since importing socket causes an import # cycle though: # google.net.proto.ProtocolBuffer imports... # httplib imports ... # socket imports ... # remote_socket_service_pb imports ProtocolBuffer _GLOBAL_DEFAULT_TIMEOUT = object() _IMPLEMENTATION = 'gae' class HTTPMessage(mimetools.Message): # App Engine Note: This class has been copied almost unchanged from # Python 2.7.2 def addheader(self, key, value): """Add header for field key handling repeats.""" prev = self.dict.get(key) if prev is None: self.dict[key] = value else: combined = ", ".join((prev, value)) self.dict[key] = combined def addcontinue(self, key, more): """Add more field data from a continuation line.""" prev = self.dict[key] self.dict[key] = prev + "\n " + more def readheaders(self): """Read header lines. Read header lines up to the entirely blank line that terminates them. The (normally blank) line that ends the headers is skipped, but not included in the returned list. If a non-header line ends the headers, (which is an error), an attempt is made to backspace over it; it is never included in the returned list. The variable self.status is set to the empty string if all went well, otherwise it is an error message. The variable self.headers is a completely uninterpreted list of lines contained in the header (so printing them will reproduce the header exactly as it appears in the file). If multiple header fields with the same name occur, they are combined according to the rules in RFC 2616 sec 4.2: Appending each subsequent field-value to the first, each separated by a comma. The order in which header fields with the same field-name are received is significant to the interpretation of the combined field value. """ # XXX The implementation overrides the readheaders() method of # rfc822.Message. The base class design isn't amenable to # customized behavior here so the method here is a copy of the # base class code with a few small changes. self.dict = {} self.unixfrom = '' self.headers = hlist = [] self.status = '' headerseen = "" firstline = 1 startofline = unread = tell = None if hasattr(self.fp, 'unread'): unread = self.fp.unread elif self.seekable: tell = self.fp.tell while True: if tell: try: startofline = tell() except IOError: startofline = tell = None self.seekable = 0 line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") if not line: self.status = 'EOF in headers' break # Skip unix From name time lines if firstline and line.startswith('From '): self.unixfrom = self.unixfrom + line continue firstline = 0 if headerseen and line[0] in ' \t': # XXX Not sure if continuation lines are handled properly # for http and/or for repeating headers # It's a continuation line. hlist.append(line) self.addcontinue(headerseen, line.strip()) continue elif self.iscomment(line): # It's a comment. Ignore it. continue elif self.islast(line): # Note! No pushback here! The delimiter line gets eaten. break headerseen = self.isheader(line) if headerseen: # It's a legal header line, save it. hlist.append(line) self.addheader(headerseen, line[len(headerseen)+1:].strip()) continue else: # It's not a header line; throw it back and stop here. if not self.dict: self.status = 'No headers' else: self.status = 'Non-header line where header expected' # Try to undo the read. if unread: unread(line) elif tell: self.fp.seek(startofline) else: self.status = self.status + '; bad seek' break class HTTPResponse: # App Engine Note: The public interface is identical to the interface provided # in Python 2.7 except __init__ takes a # google.appengine.api.urlfetch.Response instance rather than a socket. def __init__(self, fetch_response, # App Engine Note: fetch_response was "sock". debuglevel=0, strict=0, method=None, buffering=False): self._fetch_response = fetch_response self.fp = cStringIO.StringIO(fetch_response.content) # For the HTTP class. self.debuglevel = debuglevel self.strict = strict self._method = method self.msg = None # from the Status-Line of the response self.version = _UNKNOWN # HTTP-Version self.status = _UNKNOWN # Status-Code self.reason = _UNKNOWN # Reason-Phrase self.chunked = _UNKNOWN # is "chunked" being used? self.chunk_left = _UNKNOWN # bytes left to read in current chunk self.length = _UNKNOWN # number of bytes left in response self.will_close = _UNKNOWN # conn will close at end of response def begin(self): if self.msg is not None: # we've already started reading the response return self.msg = self._fetch_response.header_msg self.version = 11 # We can't get the real HTTP version so make one up. self.status = self._fetch_response.status_code self.reason = responses.get(self._fetch_response.status_code, 'Unknown') # The following are implementation details and should not be read by # clients - but set them to reasonable values just in case. self.chunked = 0 self.chunk_left = None self.length = None self.will_close = 1 def close(self): if self.fp: self.fp.close() self.fp = None def isclosed(self): return self.fp is None def read(self, amt=None): if self.fp is None: return '' if self._method == 'HEAD': self.close() return '' if amt is None: return self.fp.read() else: return self.fp.read(amt) def fileno(self): raise NotImplementedError('fileno is not supported') def getheader(self, name, default=None): if self.msg is None: raise ResponseNotReady() return self.msg.getheader(name, default) def getheaders(self): """Return list of (header, value) tuples.""" if self.msg is None: raise ResponseNotReady() return self.msg.items() class HTTPConnection: # App Engine Note: The public interface is identical to the interface provided # in Python 2.7.2 but the implementation uses # google.appengine.api.urlfetch. Some methods are no-ops and set_tunnel # raises NotImplementedError. _protocol = 'http' # passed to urlfetch. _http_vsn = 11 _http_vsn_str = 'HTTP/1.1' response_class = HTTPResponse default_port = HTTP_PORT auto_open = 1 debuglevel = 0 strict = 0 _allow_truncated = True _follow_redirects = False # pylint: disable=unused-argument def __init__(self, host, port=None, strict=None, timeout=_GLOBAL_DEFAULT_TIMEOUT, source_address=None, context=None): # net.proto.ProcotolBuffer relies on httplib so importing urlfetch at the # module level causes a failure on prod. That means the import needs to be # lazy. from google.appengine.api import urlfetch self._fetch = urlfetch.fetch self._method_map = { 'GET': urlfetch.GET, 'POST': urlfetch.POST, 'HEAD': urlfetch.HEAD, 'PUT': urlfetch.PUT, 'DELETE': urlfetch.DELETE, 'PATCH': urlfetch.PATCH, } self.host = host self.port = port # With urllib2 in Python 2.6, an object can be passed here. # The default is set to socket.GLOBAL_DEFAULT_TIMEOUT which is an object. # We only accept float, int or long values, otherwise it can be # silently ignored. if not isinstance(timeout, (float, int, long)): timeout = None self.timeout = timeout # Both 'strict' and 'source_address' are ignored. self._method = self._url = None self._body = '' self.headers = [] def set_tunnel(self, host, port=None, headers=None): """ Sets up the host and the port for the HTTP CONNECT Tunnelling. The headers argument should be a mapping of extra HTTP headers to send with the CONNECT request. App Engine Note: This method is not supported. """ raise NotImplementedError('HTTP CONNECT Tunnelling is not supported') def set_debuglevel(self, level): pass def connect(self): """Connect to the host and port specified in __init__. App Engine Note: This method is a no-op. """ def close(self): """Close the connection to the HTTP server. App Engine Note: This method is a no-op. """ def send(self, data): """Send `data' to the server.""" self._body += data def putrequest(self, method, url, skip_host=0, skip_accept_encoding=0): """Send a request to the server. `method' specifies an HTTP request method, e.g. 'GET'. `url' specifies the object being requested, e.g. '/index.html'. `skip_host' if True does not add automatically a 'Host:' header `skip_accept_encoding' if True does not add automatically an 'Accept-Encoding:' header App Engine Note: `skip_host' and `skip_accept_encoding' are not honored by the urlfetch service. """ self._method = method self._url = url def putheader(self, header, *values): """Send a request header line to the server. For example: h.putheader('Accept', 'text/html') """ hdr = '\r\n\t'.join([str(v) for v in values]) self.headers.append((header, hdr)) def endheaders(self, message_body=None): """Indicate that the last header line has been sent to the server. This method sends the request to the server. The optional message_body argument can be used to pass message body associated with the request. The message body will be sent in the same packet as the message headers if possible. The message_body should be a string. """ if message_body is not None: self.send(message_body) def request(self, method, url, body=None, headers=None): """Send a complete request to the server.""" self._method = method self._url = url try: # 'body' can be a file. self._body = body.read() except AttributeError: self._body = body if headers is None: headers = [] elif hasattr(headers, 'items'): headers = headers.items() self.headers = headers @staticmethod def _getargspec(callable_object): assert callable(callable_object) try: # Methods and lambdas. return inspect.getargspec(callable_object) except TypeError: # Class instances with __call__. return inspect.getargspec(callable_object.__call__) def getresponse(self, buffering=False): """Get the response from the server. App Engine Note: buffering is ignored. """ # net.proto.ProcotolBuffer relies on httplib so importing urlfetch at the # module level causes a failure on prod. That means the import needs to be # lazy. from google.appengine.api import urlfetch import socket # Cannot be done at global scope due to circular import. if self.port and self.port != self.default_port: host = '%s:%s' % (self.host, self.port) else: host = self.host if not self._url.startswith(self._protocol): url = '%s://%s%s' % (self._protocol, host, self._url) else: url = self._url headers = dict(self.headers) if self.timeout in [_GLOBAL_DEFAULT_TIMEOUT, socket._GLOBAL_DEFAULT_TIMEOUT]: deadline = socket.getdefaulttimeout() else: deadline = self.timeout try: method = self._method_map[self._method.upper()] except KeyError: raise ValueError('%r is an unrecognized HTTP method' % self._method) try: # The Python Standard Library doesn't validate certificates so don't # validate them here either. But some libraries (httplib2, possibly # others) use an alternate technique where the fetch function does not # have a validate_certificate argument so only provide it when supported. argspec = self._getargspec(self._fetch) extra_kwargs = ( {'validate_certificate': False} if argspec.keywords or 'validate_certificate' in argspec.args else {}) fetch_response = self._fetch(url, self._body, method, headers, self._allow_truncated, self._follow_redirects, deadline, **extra_kwargs) except urlfetch.InvalidURLError, e: raise InvalidURL(str(e)) except (urlfetch.ResponseTooLargeError, urlfetch.DeadlineExceededError), e: raise HTTPException(str(e)) except urlfetch.SSLCertificateError, e: # Should be ssl.SSLError but the ssl module isn't available. # Continue to support this exception for versions of _fetch that do not # support validate_certificates. Also, in production App Engine defers # specific semantics so leaving this in just in case. raise HTTPException(str(e)) except urlfetch.DownloadError, e: # One of the following occured: UNSPECIFIED_ERROR, FETCH_ERROR raise socket.error( 'An error occured while connecting to the server: %s' % e) response = self.response_class(fetch_response, method=method) response.begin() self.close() return response class HTTPSConnection(HTTPConnection): "This class allows communication via SSL." # App Engine Note: The public interface is identical to the interface provided # in Python 2.7.2 but the implementation does not support key and # certificate files. _protocol = 'https' # passed to urlfetch. default_port = HTTPS_PORT # pylint: disable=unused-argument def __init__(self, host, port=None, key_file=None, cert_file=None, strict=False, timeout=_GLOBAL_DEFAULT_TIMEOUT, source_address=None, context=None): if key_file is not None or cert_file is not None: raise NotImplementedError( 'key_file and cert_file arguments are not implemented') HTTPConnection.__init__(self, host, port, strict, timeout, source_address) class HTTP: "Compatibility class with httplib.py from 1.5." # App Engine Note: The public interface is identical to the interface provided # in Python 2.7. _http_vsn = 10 _http_vsn_str = 'HTTP/1.0' debuglevel = 0 _connection_class = HTTPConnection def __init__(self, host='', port=None, strict=None): "Provide a default host, since the superclass requires one." # some joker passed 0 explicitly, meaning default port if port == 0: port = None # Note that we may pass an empty string as the host; this will throw # an error when we attempt to connect. Presumably, the client code # will call connect before then, with a proper host. self._setup(self._connection_class(host, port, strict)) def _setup(self, conn): self._conn = conn # set up delegation to flesh out interface self.send = conn.send self.putrequest = conn.putrequest self.endheaders = conn.endheaders self.set_debuglevel = conn.set_debuglevel conn._http_vsn = self._http_vsn conn._http_vsn_str = self._http_vsn_str self.file = None def connect(self, host=None, port=None): "Accept arguments to set the host/port, since the superclass doesn't." self.__init__(host, port) def getfile(self): "Provide a getfile, since the superclass' does not use this concept." return self.file def putheader(self, header, *values): "The superclass allows only one value argument." self._conn.putheader(header, '\r\n\t'.join([str(v) for v in values])) def getreply(self, buffering=False): """Compat definition since superclass does not define it. Returns a tuple consisting of: - server status code (e.g. '200' if all goes well) - server "reason" corresponding to status code - any RFC822 headers in the response from the server """ response = self._conn.getresponse() self.headers = response.msg self.file = response.fp return response.status, response.reason, response.msg def close(self): self._conn.close() # note that self.file == response.fp, which gets closed by the # superclass. just clear the object ref here. ### hmm. messy. if status==-1, then self.file is owned by us. ### well... we aren't explicitly closing, but losing this ref will ### do it self.file = None # Copy from Python's httplib implementation. class HTTPS(HTTP): """Compatibility with 1.5 httplib interface Python 1.5.2 did not have an HTTPS class, but it defined an interface for sending http requests that is also useful for https. """ # App Engine Note: The public interface is identical to the interface provided # in Python 2.7 except that key and certificate files are not supported. _connection_class = HTTPSConnection def __init__(self, host='', port=None, key_file=None, cert_file=None, strict=None): if key_file is not None or cert_file is not None: raise NotImplementedError( 'key_file and cert_file arguments are not implemented') # provide a default host, pass the X509 cert info # urf. compensate for bad input. if port == 0: port = None self._setup(self._connection_class(host, port, key_file, cert_file, strict)) # we never actually use these for anything, but we keep them # here for compatibility with post-1.5.2 CVS. self.key_file = key_file self.cert_file = cert_file class HTTPException(Exception): # App Engine Note: This class has been copied unchanged from Python 2.7.2 # Subclasses that define an __init__ must call Exception.__init__ # or define self.args. Otherwise, str() will fail. pass class NotConnected(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class InvalidURL(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class UnknownProtocol(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 def __init__(self, version): self.args = version, self.version = version class UnknownTransferEncoding(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class UnimplementedFileMode(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class IncompleteRead(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 def __init__(self, partial, expected=None): self.args = partial, self.partial = partial self.expected = expected def __repr__(self): if self.expected is not None: e = ', %i more expected' % self.expected else: e = '' return 'IncompleteRead(%i bytes read%s)' % (len(self.partial), e) def __str__(self): return repr(self) class ImproperConnectionState(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class CannotSendRequest(ImproperConnectionState): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class CannotSendHeader(ImproperConnectionState): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class ResponseNotReady(ImproperConnectionState): # App Engine Note: This class has been copied unchanged from Python 2.7.2 pass class BadStatusLine(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 def __init__(self, line): if not line: line = repr(line) self.args = line, self.line = line class LineTooLong(HTTPException): # App Engine Note: This class has been copied unchanged from Python 2.7.2 def __init__(self, line_type): HTTPException.__init__(self, "got more than %d bytes when reading %s" % (_MAXLINE, line_type)) # for backwards compatibility error = HTTPException class LineAndFileWrapper: """A limited file-like object for HTTP/0.9 responses.""" # App Engine Note: This class has been copied unchanged from Python 2.7.2 # The status-line parsing code calls readline(), which normally # get the HTTP status line. For a 0.9 response, however, this is # actually the first line of the body! Clients need to get a # readable file object that contains that line. def __init__(self, line, file): self._line = line self._file = file self._line_consumed = 0 self._line_offset = 0 self._line_left = len(line) def __getattr__(self, attr): return getattr(self._file, attr) def _done(self): # called when the last byte is read from the line. After the # call, all read methods are delegated to the underlying file # object. self._line_consumed = 1 self.read = self._file.read self.readline = self._file.readline self.readlines = self._file.readlines def read(self, amt=None): if self._line_consumed: return self._file.read(amt) assert self._line_left if amt is None or amt > self._line_left: s = self._line[self._line_offset:] self._done() if amt is None: return s + self._file.read() else: return s + self._file.read(amt - len(s)) else: assert amt <= self._line_left i = self._line_offset j = i + amt s = self._line[i:j] self._line_offset = j self._line_left -= amt if self._line_left == 0: self._done() return s def readline(self): if self._line_consumed: return self._file.readline() assert self._line_left s = self._line[self._line_offset:] self._done() return s def readlines(self, size=None): if self._line_consumed: return self._file.readlines(size) assert self._line_left L = [self._line[self._line_offset:]] self._done() if size is None: return L + self._file.readlines() else: return L + self._file.readlines(size)