import errno import os import sys import time import traceback import types import warnings from eventlet.green import urllib from eventlet.green import socket from eventlet.green import BaseHTTPServer from eventlet import greenpool from eventlet import greenio from eventlet.support import get_errno DEFAULT_MAX_SIMULTANEOUS_REQUESTS = 1024 DEFAULT_MAX_HTTP_VERSION = 'HTTP/1.1' MAX_REQUEST_LINE = 8192 MAX_HEADER_LINE = 8192 MAX_TOTAL_HEADER_SIZE = 65536 MINIMUM_CHUNK_SIZE = 4096 # %(client_port)s is also available DEFAULT_LOG_FORMAT= ('%(client_ip)s - - [%(date_time)s] "%(request_line)s"' ' %(status_code)s %(body_length)s %(wall_seconds).6f') __all__ = ['server', 'format_date_time'] # Weekday and month names for HTTP date/time formatting; always English! _weekdayname = ["Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"] _monthname = [None, # Dummy so we can use 1-based month numbers "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"] def format_date_time(timestamp): """Formats a unix timestamp into an HTTP standard string.""" year, month, day, hh, mm, ss, wd, _y, _z = time.gmtime(timestamp) return "%s, %02d %3s %4d %02d:%02d:%02d GMT" % ( _weekdayname[wd], day, _monthname[month], year, hh, mm, ss ) # Collections of error codes to compare against. Not all attributes are set # on errno module on all platforms, so some are literals :( BAD_SOCK = set((errno.EBADF, 10053)) BROKEN_SOCK = set((errno.EPIPE, errno.ECONNRESET)) # special flag return value for apps class _AlreadyHandled(object): def __iter__(self): return self def next(self): raise StopIteration ALREADY_HANDLED = _AlreadyHandled() class Input(object): def __init__(self, rfile, content_length, wfile=None, wfile_line=None, chunked_input=False): self.rfile = rfile if content_length is not None: content_length = int(content_length) self.content_length = content_length self.wfile = wfile self.wfile_line = wfile_line self.position = 0 self.chunked_input = chunked_input self.chunk_length = -1 def _do_read(self, reader, length=None): if self.wfile is not None: ## 100 Continue self.wfile.write(self.wfile_line) self.wfile = None self.wfile_line = None if length is None and self.content_length is not None: length = self.content_length - self.position if length and length > self.content_length - self.position: length = self.content_length - self.position if not length: return '' try: read = reader(length) except greenio.SSL.ZeroReturnError: read = '' self.position += len(read) return read def _chunked_read(self, rfile, length=None, use_readline=False): if self.wfile is not None: ## 100 Continue self.wfile.write(self.wfile_line) self.wfile = None self.wfile_line = None try: if length == 0: return "" if length < 0: length = None if use_readline: reader = self.rfile.readline else: reader = self.rfile.read response = [] while self.chunk_length != 0: maxreadlen = self.chunk_length - self.position if length is not None and length < maxreadlen: maxreadlen = length if maxreadlen > 0: data = reader(maxreadlen) if not data: self.chunk_length = 0 raise IOError("unexpected end of file while parsing chunked data") datalen = len(data) response.append(data) self.position += datalen if self.chunk_length == self.position: rfile.readline() if length is not None: length -= datalen if length == 0: break if use_readline and data[-1] == "\n": break else: self.chunk_length = int(rfile.readline().split(";", 1)[0], 16) self.position = 0 if self.chunk_length == 0: rfile.readline() except greenio.SSL.ZeroReturnError: pass return ''.join(response) def read(self, length=None): if self.chunked_input: return self._chunked_read(self.rfile, length) return self._do_read(self.rfile.read, length) def readline(self, size=None): if self.chunked_input: return self._chunked_read(self.rfile, size, True) else: return self._do_read(self.rfile.readline, size) def readlines(self, hint=None): return self._do_read(self.rfile.readlines, hint) def __iter__(self): return iter(self.read()) def get_socket(self): return self.rfile._sock class HeaderLineTooLong(Exception): pass class HeadersTooLarge(Exception): pass class FileObjectForHeaders(object): def __init__(self, fp): self.fp = fp self.total_header_size = 0 def readline(self, size=-1): sz = size if size < 0: sz = MAX_HEADER_LINE rv = self.fp.readline(sz) if size < 0 and len(rv) >= MAX_HEADER_LINE: raise HeaderLineTooLong() self.total_header_size += len(rv) if self.total_header_size > MAX_TOTAL_HEADER_SIZE: raise HeadersTooLarge() return rv class HttpProtocol(BaseHTTPServer.BaseHTTPRequestHandler): protocol_version = 'HTTP/1.1' minimum_chunk_size = MINIMUM_CHUNK_SIZE def setup(self): # overriding SocketServer.setup to correctly handle SSL.Connection objects conn = self.connection = self.request try: self.rfile = conn.makefile('rb', self.rbufsize) self.wfile = conn.makefile('wb', self.wbufsize) except (AttributeError, NotImplementedError): if hasattr(conn, 'send') and hasattr(conn, 'recv'): # it's an SSL.Connection self.rfile = socket._fileobject(conn, "rb", self.rbufsize) self.wfile = socket._fileobject(conn, "wb", self.wbufsize) else: # it's a SSLObject, or a martian raise NotImplementedError("wsgi.py doesn't support sockets "\ "of type %s" % type(conn)) def handle_one_request(self): if self.server.max_http_version: self.protocol_version = self.server.max_http_version if self.rfile.closed: self.close_connection = 1 return try: self.raw_requestline = self.rfile.readline(self.server.url_length_limit) if len(self.raw_requestline) == self.server.url_length_limit: self.wfile.write( "HTTP/1.0 414 Request URI Too Long\r\n" "Connection: close\r\nContent-length: 0\r\n\r\n") self.close_connection = 1 return except greenio.SSL.ZeroReturnError: self.raw_requestline = '' except socket.error, e: if get_errno(e) not in BAD_SOCK: raise self.raw_requestline = '' if not self.raw_requestline: self.close_connection = 1 return orig_rfile = self.rfile try: self.rfile = FileObjectForHeaders(self.rfile) if not self.parse_request(): return except HeaderLineTooLong: self.wfile.write( "HTTP/1.0 400 Header Line Too Long\r\n" "Connection: close\r\nContent-length: 0\r\n\r\n") self.close_connection = 1 return except HeadersTooLarge: self.wfile.write( "HTTP/1.0 400 Headers Too Large\r\n" "Connection: close\r\nContent-length: 0\r\n\r\n") self.close_connection = 1 return finally: self.rfile = orig_rfile content_length = self.headers.getheader('content-length') if content_length: try: int(content_length) except ValueError: self.wfile.write( "HTTP/1.0 400 Bad Request\r\n" "Connection: close\r\nContent-length: 0\r\n\r\n") self.close_connection = 1 return self.environ = self.get_environ() self.application = self.server.app try: self.server.outstanding_requests += 1 try: self.handle_one_response() except socket.error, e: # Broken pipe, connection reset by peer if get_errno(e) not in BROKEN_SOCK: raise finally: self.server.outstanding_requests -= 1 def handle_one_response(self): start = time.time() headers_set = [] headers_sent = [] wfile = self.wfile result = None use_chunked = [False] length = [0] status_code = [200] def write(data, _writelines=wfile.writelines): towrite = [] if not headers_set: raise AssertionError("write() before start_response()") elif not headers_sent: status, response_headers = headers_set headers_sent.append(1) header_list = [header[0].lower() for header in response_headers] towrite.append('%s %s\r\n' % (self.protocol_version, status)) for header in response_headers: towrite.append('%s: %s\r\n' % header) # send Date header? if 'date' not in header_list: towrite.append('Date: %s\r\n' % (format_date_time(time.time()),)) client_conn = self.headers.get('Connection', '').lower() send_keep_alive = False if self.close_connection == 0 and \ self.server.keepalive and (client_conn == 'keep-alive' or \ (self.request_version == 'HTTP/1.1' and not client_conn == 'close')): # only send keep-alives back to clients that sent them, # it's redundant for 1.1 connections send_keep_alive = (client_conn == 'keep-alive') self.close_connection = 0 else: self.close_connection = 1 if 'content-length' not in header_list: if self.request_version == 'HTTP/1.1': use_chunked[0] = True towrite.append('Transfer-Encoding: chunked\r\n') elif 'content-length' not in header_list: # client is 1.0 and therefore must read to EOF self.close_connection = 1 if self.close_connection: towrite.append('Connection: close\r\n') elif send_keep_alive: towrite.append('Connection: keep-alive\r\n') towrite.append('\r\n') # end of header writing if use_chunked[0]: ## Write the chunked encoding towrite.append("%x\r\n%s\r\n" % (len(data), data)) else: towrite.append(data) try: _writelines(towrite) length[0] = length[0] + sum(map(len, towrite)) except UnicodeEncodeError: self.server.log_message("Encountered non-ascii unicode while attempting to write wsgi response: %r" % [x for x in towrite if isinstance(x, unicode)]) self.server.log_message(traceback.format_exc()) _writelines( ["HTTP/1.1 500 Internal Server Error\r\n", "Connection: close\r\n", "Content-type: text/plain\r\n", "Content-length: 98\r\n", "Date: %s\r\n" % format_date_time(time.time()), "\r\n", ("Internal Server Error: wsgi application passed " "a unicode object to the server instead of a string.")]) def start_response(status, response_headers, exc_info=None): status_code[0] = status.split()[0] if exc_info: try: if headers_sent: # Re-raise original exception if headers sent raise exc_info[0], exc_info[1], exc_info[2] finally: # Avoid dangling circular ref exc_info = None capitalized_headers = [('-'.join([x.capitalize() for x in key.split('-')]), value) for key, value in response_headers] headers_set[:] = [status, capitalized_headers] return write try: try: result = self.application(self.environ, start_response) if (isinstance(result, _AlreadyHandled) or isinstance(getattr(result, '_obj', None), _AlreadyHandled)): self.close_connection = 1 return if not headers_sent and hasattr(result, '__len__') and \ 'Content-Length' not in [h for h, _v in headers_set[1]]: headers_set[1].append(('Content-Length', str(sum(map(len, result))))) towrite = [] towrite_size = 0 just_written_size = 0 for data in result: towrite.append(data) towrite_size += len(data) if towrite_size >= self.minimum_chunk_size: write(''.join(towrite)) towrite = [] just_written_size = towrite_size towrite_size = 0 if towrite: just_written_size = towrite_size write(''.join(towrite)) if not headers_sent or (use_chunked[0] and just_written_size): write('') except Exception: self.close_connection = 1 tb = traceback.format_exc() self.server.log_message(tb) if not headers_set: err_body = "" if(self.server.debug): err_body = tb start_response("500 Internal Server Error", [('Content-type', 'text/plain'), ('Content-length', len(err_body))]) write(err_body) finally: if hasattr(result, 'close'): result.close() if (self.environ['eventlet.input'].chunked_input or self.environ['eventlet.input'].position \ < self.environ['eventlet.input'].content_length): ## Read and discard body if there was no pending 100-continue if not self.environ['eventlet.input'].wfile: # NOTE: MINIMUM_CHUNK_SIZE is used here for purpose different than chunking. # We use it only cause it's at hand and has reasonable value in terms of # emptying the buffer. while self.environ['eventlet.input'].read(MINIMUM_CHUNK_SIZE): pass finish = time.time() for hook, args, kwargs in self.environ['eventlet.posthooks']: hook(self.environ, *args, **kwargs) if self.server.log_output: self.server.log_message(self.server.log_format % { 'client_ip': self.get_client_ip(), 'client_port': self.client_address[1], 'date_time': self.log_date_time_string(), 'request_line': self.requestline, 'status_code': status_code[0], 'body_length': length[0], 'wall_seconds': finish - start, }) def get_client_ip(self): client_ip = self.client_address[0] if self.server.log_x_forwarded_for: forward = self.headers.get('X-Forwarded-For', '').replace(' ', '') if forward: client_ip = "%s,%s" % (forward, client_ip) return client_ip def get_environ(self): env = self.server.get_environ() env['REQUEST_METHOD'] = self.command env['SCRIPT_NAME'] = '' pq = self.path.split('?', 1) env['RAW_PATH_INFO'] = pq[0] env['PATH_INFO'] = urllib.unquote(pq[0]) if len(pq) > 1: env['QUERY_STRING'] = pq[1] if self.headers.typeheader is None: env['CONTENT_TYPE'] = self.headers.type else: env['CONTENT_TYPE'] = self.headers.typeheader length = self.headers.getheader('content-length') if length: env['CONTENT_LENGTH'] = length env['SERVER_PROTOCOL'] = 'HTTP/1.0' host, port = self.request.getsockname()[:2] env['SERVER_NAME'] = host env['SERVER_PORT'] = str(port) env['REMOTE_ADDR'] = self.client_address[0] env['REMOTE_PORT'] = str(self.client_address[1]) env['GATEWAY_INTERFACE'] = 'CGI/1.1' for h in self.headers.headers: k, v = h.split(':', 1) k = k.replace('-', '_').upper() v = v.strip() if k in env: continue envk = 'HTTP_' + k if envk in env: env[envk] += ',' + v else: env[envk] = v if env.get('HTTP_EXPECT') == '100-continue': wfile = self.wfile wfile_line = 'HTTP/1.1 100 Continue\r\n\r\n' else: wfile = None wfile_line = None chunked = env.get('HTTP_TRANSFER_ENCODING', '').lower() == 'chunked' env['wsgi.input'] = env['eventlet.input'] = Input( self.rfile, length, wfile=wfile, wfile_line=wfile_line, chunked_input=chunked) env['eventlet.posthooks'] = [] return env def finish(self): try: BaseHTTPServer.BaseHTTPRequestHandler.finish(self) except socket.error, e: # Broken pipe, connection reset by peer if get_errno(e) not in BROKEN_SOCK: raise greenio.shutdown_safe(self.connection) self.connection.close() class Server(BaseHTTPServer.HTTPServer): def __init__(self, socket, address, app, log=None, environ=None, max_http_version=None, protocol=HttpProtocol, minimum_chunk_size=None, log_x_forwarded_for=True, keepalive=True, log_output=True, log_format=DEFAULT_LOG_FORMAT, url_length_limit=MAX_REQUEST_LINE, debug=True): self.outstanding_requests = 0 self.socket = socket self.address = address if log: self.log = log else: self.log = sys.stderr self.app = app self.keepalive = keepalive self.environ = environ self.max_http_version = max_http_version self.protocol = protocol self.pid = os.getpid() self.minimum_chunk_size = minimum_chunk_size self.log_x_forwarded_for = log_x_forwarded_for self.log_output = log_output self.log_format = log_format self.url_length_limit = url_length_limit self.debug = debug def get_environ(self): d = { 'wsgi.errors': sys.stderr, 'wsgi.version': (1, 0), 'wsgi.multithread': True, 'wsgi.multiprocess': False, 'wsgi.run_once': False, 'wsgi.url_scheme': 'http', } # detect secure socket if hasattr(self.socket, 'do_handshake'): d['wsgi.url_scheme'] = 'https' d['HTTPS'] = 'on' if self.environ is not None: d.update(self.environ) return d def process_request(self, (socket, address)): # The actual request handling takes place in __init__, so we need to # set minimum_chunk_size before __init__ executes and we don't want to modify # class variable proto = types.InstanceType(self.protocol) if self.minimum_chunk_size is not None: proto.minimum_chunk_size = self.minimum_chunk_size proto.__init__(socket, address, self) def log_message(self, message): self.log.write(message + '\n') try: import ssl ACCEPT_EXCEPTIONS = (socket.error, ssl.SSLError) ACCEPT_ERRNO = set((errno.EPIPE, errno.EBADF, errno.ECONNRESET, ssl.SSL_ERROR_EOF, ssl.SSL_ERROR_SSL)) except ImportError: ACCEPT_EXCEPTIONS = (socket.error,) ACCEPT_ERRNO = set((errno.EPIPE, errno.EBADF, errno.ECONNRESET)) def server(sock, site, log=None, environ=None, max_size=None, max_http_version=DEFAULT_MAX_HTTP_VERSION, protocol=HttpProtocol, server_event=None, minimum_chunk_size=None, log_x_forwarded_for=True, custom_pool=None, keepalive=True, log_output=True, log_format=DEFAULT_LOG_FORMAT, url_length_limit=MAX_REQUEST_LINE, debug=True): """ Start up a wsgi server handling requests from the supplied server socket. This function loops forever. The *sock* object will be closed after server exits, but the underlying file descriptor will remain open, so if you have a dup() of *sock*, it will remain usable. :param sock: Server socket, must be already bound to a port and listening. :param site: WSGI application function. :param log: File-like object that logs should be written to. If not specified, sys.stderr is used. :param environ: Additional parameters that go into the environ dictionary of every request. :param max_size: Maximum number of client connections opened at any time by this server. :param max_http_version: Set to "HTTP/1.0" to make the server pretend it only supports HTTP 1.0. This can help with applications or clients that don't behave properly using HTTP 1.1. :param protocol: Protocol class. Deprecated. :param server_event: Used to collect the Server object. Deprecated. :param minimum_chunk_size: Minimum size in bytes for http chunks. This can be used to improve performance of applications which yield many small strings, though using it technically violates the WSGI spec. :param log_x_forwarded_for: If True (the default), logs the contents of the x-forwarded-for header in addition to the actual client ip address in the 'client_ip' field of the log line. :param custom_pool: A custom GreenPool instance which is used to spawn client green threads. If this is supplied, max_size is ignored. :param keepalive: If set to False, disables keepalives on the server; all connections will be closed after serving one request. :param log_output: A Boolean indicating if the server will log data or not. :param log_format: A python format string that is used as the template to generate log lines. The following values can be formatted into it: client_ip, date_time, request_line, status_code, body_length, wall_seconds. The default is a good example of how to use it. :param url_length_limit: A maximum allowed length of the request url. If exceeded, 414 error is returned. :param debug: True if the server should send exception tracebacks to the clients on 500 errors. If False, the server will respond with empty bodies. """ serv = Server(sock, sock.getsockname(), site, log, environ=environ, max_http_version=max_http_version, protocol=protocol, minimum_chunk_size=minimum_chunk_size, log_x_forwarded_for=log_x_forwarded_for, keepalive=keepalive, log_output=log_output, log_format=log_format, url_length_limit=url_length_limit, debug=debug) if server_event is not None: server_event.send(serv) if max_size is None: max_size = DEFAULT_MAX_SIMULTANEOUS_REQUESTS if custom_pool is not None: pool = custom_pool else: pool = greenpool.GreenPool(max_size) try: host, port = sock.getsockname()[:2] port = ':%s' % (port, ) if hasattr(sock, 'do_handshake'): scheme = 'https' if port == ':443': port = '' else: scheme = 'http' if port == ':80': port = '' serv.log.write("(%s) wsgi starting up on %s://%s%s/\n" % ( serv.pid, scheme, host, port)) while True: try: client_socket = sock.accept() if debug: serv.log.write("(%s) accepted %r\n" % ( serv.pid, client_socket[1])) try: pool.spawn_n(serv.process_request, client_socket) except AttributeError: warnings.warn("wsgi's pool should be an instance of " \ "eventlet.greenpool.GreenPool, is %s. Please convert your"\ " call site to use GreenPool instead" % type(pool), DeprecationWarning, stacklevel=2) pool.execute_async(serv.process_request, client_socket) except ACCEPT_EXCEPTIONS, e: if get_errno(e) not in ACCEPT_ERRNO: raise except (KeyboardInterrupt, SystemExit): serv.log.write("wsgi exiting\n") break finally: try: # NOTE: It's not clear whether we want this to leave the # socket open or close it. Use cases like Spawning want # the underlying fd to remain open, but if we're going # that far we might as well not bother closing sock at # all. sock.close() except socket.error, e: if get_errno(e) not in BROKEN_SOCK: traceback.print_exc()