Files
deb-python-eventlet/eventlet/wsgi.py
Jakub Stasiak 6afd8bdee2 Python 3 compatibility fixes
Closes GH-102
Closes GH-103
Closes GH-104
2014-07-18 02:12:53 +04:00

765 lines
29 KiB
Python

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, six
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
__next__ = next
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(b";", 1)[0], 16)
self.position = 0
if self.chunk_length == 0:
rfile.readline()
except greenio.SSL.ZeroReturnError:
pass
return b''.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
capitalize_response_headers = True
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 as 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.get('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 as 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, six.text_type)])
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
six.reraise(exc_info[0], exc_info[1], exc_info[2])
finally:
# Avoid dangling circular ref
exc_info = None
# Response headers capitalization
# CONTent-TYpe: TExt/PlaiN -> Content-Type: TExt/PlaiN
# Per HTTP RFC standard, header name is case-insensitive.
# Please, fix your client to ignore header case if possible.
if self.capitalize_response_headers:
response_headers = [
('-'.join([x.capitalize() for x in key.split('-')]), value)
for key, value in response_headers]
headers_set[:] = [status, response_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
# Set content-length if possible
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
minimum_write_chunk_size = int(self.environ.get(
'eventlet.minimum_write_chunk_size', self.minimum_chunk_size))
for data in result:
towrite.append(data)
towrite_size += len(data)
if towrite_size >= minimum_write_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]
ct = self.headers.get('content-type')
if ct is None:
try:
ct = self.headers.type
except AttributeError:
ct = self.headers.get_content_type()
env['CONTENT_TYPE'] = ct
length = self.headers.get('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'
try:
headers = self.headers.headers
except AttributeError:
headers = self.headers._headers
else:
headers = [h.split(':', 1) for h in headers]
for k, v in headers:
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 as 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,
socket_timeout=None,
capitalize_response_headers=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
self.socket_timeout = socket_timeout
self.capitalize_response_headers = capitalize_response_headers
if not self.capitalize_response_headers:
warnings.warn("""capitalize_response_headers is disabled.
Please, make sure you know what you are doing.
HTTP headers names are case-insensitive per RFC standard.
Most likely, you need to fix HTTP parsing in your client software.""",
DeprecationWarning, stacklevel=3)
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, sock_params):
# 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
sock, address = sock_params
proto = new(self.protocol)
if self.minimum_chunk_size is not None:
proto.minimum_chunk_size = self.minimum_chunk_size
proto.capitalize_response_headers = self.capitalize_response_headers
try:
proto.__init__(sock, address, self)
except socket.timeout:
# Expected exceptions are not exceptional
sock.close()
if self.debug:
# similar to logging "accepted" in server()
self.log_message('(%s) timed out %r' % (self.pid, address))
def log_message(self, message):
self.log.write(message + '\n')
try:
new = types.InstanceType
except AttributeError:
new = lambda cls: cls.__new__(cls)
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,
socket_timeout=None,
capitalize_response_headers=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. This can be overridden on a per request basis by setting environ['eventlet.minimum_write_chunk_size'].
: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.
:param socket_timeout: Timeout for client connections' socket operations. Default None means wait forever.
:param capitalize_response_headers: Normalize response headers' names to Foo-Bar. Default is True.
"""
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,
socket_timeout=socket_timeout,
capitalize_response_headers=capitalize_response_headers,
)
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()
client_socket[0].settimeout(serv.socket_timeout)
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 as 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 as e:
if get_errno(e) not in BROKEN_SOCK:
traceback.print_exc()