You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
415 lines
16 KiB
415 lines
16 KiB
##############################################################################
|
|
#
|
|
# Copyright (c) 2001, 2002 Zope Foundation and Contributors.
|
|
# All Rights Reserved.
|
|
#
|
|
# This software is subject to the provisions of the Zope Public License,
|
|
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
|
|
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
|
|
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
|
|
# FOR A PARTICULAR PURPOSE.
|
|
#
|
|
##############################################################################
|
|
import socket
|
|
import threading
|
|
import time
|
|
import traceback
|
|
|
|
from waitress.buffers import (
|
|
OverflowableBuffer,
|
|
ReadOnlyFileBasedBuffer,
|
|
)
|
|
|
|
from waitress.parser import HTTPRequestParser
|
|
|
|
from waitress.task import (
|
|
ErrorTask,
|
|
WSGITask,
|
|
)
|
|
|
|
from waitress.utilities import InternalServerError
|
|
|
|
from . import wasyncore
|
|
|
|
|
|
class ClientDisconnected(Exception):
|
|
""" Raised when attempting to write to a closed socket."""
|
|
|
|
|
|
class HTTPChannel(wasyncore.dispatcher, object):
|
|
"""
|
|
Setting self.requests = [somerequest] prevents more requests from being
|
|
received until the out buffers have been flushed.
|
|
|
|
Setting self.requests = [] allows more requests to be received.
|
|
"""
|
|
|
|
task_class = WSGITask
|
|
error_task_class = ErrorTask
|
|
parser_class = HTTPRequestParser
|
|
|
|
request = None # A request parser instance
|
|
last_activity = 0 # Time of last activity
|
|
will_close = False # set to True to close the socket.
|
|
close_when_flushed = False # set to True to close the socket when flushed
|
|
requests = () # currently pending requests
|
|
sent_continue = False # used as a latch after sending 100 continue
|
|
total_outbufs_len = 0 # total bytes ready to send
|
|
current_outbuf_count = 0 # total bytes written to current outbuf
|
|
|
|
#
|
|
# ASYNCHRONOUS METHODS (including __init__)
|
|
#
|
|
|
|
def __init__(
|
|
self, server, sock, addr, adj, map=None,
|
|
):
|
|
self.server = server
|
|
self.adj = adj
|
|
self.outbufs = [OverflowableBuffer(adj.outbuf_overflow)]
|
|
self.creation_time = self.last_activity = time.time()
|
|
self.sendbuf_len = sock.getsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF)
|
|
|
|
# task_lock used to push/pop requests
|
|
self.task_lock = threading.Lock()
|
|
# outbuf_lock used to access any outbuf (expected to use an RLock)
|
|
self.outbuf_lock = threading.Condition()
|
|
|
|
wasyncore.dispatcher.__init__(self, sock, map=map)
|
|
|
|
# Don't let wasyncore.dispatcher throttle self.addr on us.
|
|
self.addr = addr
|
|
|
|
def writable(self):
|
|
# if there's data in the out buffer or we've been instructed to close
|
|
# the channel (possibly by our server maintenance logic), run
|
|
# handle_write
|
|
return self.total_outbufs_len or self.will_close or self.close_when_flushed
|
|
|
|
def handle_write(self):
|
|
# Precondition: there's data in the out buffer to be sent, or
|
|
# there's a pending will_close request
|
|
if not self.connected:
|
|
# we dont want to close the channel twice
|
|
return
|
|
|
|
# try to flush any pending output
|
|
if not self.requests:
|
|
# 1. There are no running tasks, so we don't need to try to lock
|
|
# the outbuf before sending
|
|
# 2. The data in the out buffer should be sent as soon as possible
|
|
# because it's either data left over from task output
|
|
# or a 100 Continue line sent within "received".
|
|
flush = self._flush_some
|
|
elif self.total_outbufs_len >= self.adj.send_bytes:
|
|
# 1. There's a running task, so we need to try to lock
|
|
# the outbuf before sending
|
|
# 2. Only try to send if the data in the out buffer is larger
|
|
# than self.adj_bytes to avoid TCP fragmentation
|
|
flush = self._flush_some_if_lockable
|
|
else:
|
|
# 1. There's not enough data in the out buffer to bother to send
|
|
# right now.
|
|
flush = None
|
|
|
|
if flush:
|
|
try:
|
|
flush()
|
|
except socket.error:
|
|
if self.adj.log_socket_errors:
|
|
self.logger.exception("Socket error")
|
|
self.will_close = True
|
|
except Exception:
|
|
self.logger.exception("Unexpected exception when flushing")
|
|
self.will_close = True
|
|
|
|
if self.close_when_flushed and not self.total_outbufs_len:
|
|
self.close_when_flushed = False
|
|
self.will_close = True
|
|
|
|
if self.will_close:
|
|
self.handle_close()
|
|
|
|
def readable(self):
|
|
# We might want to create a new task. We can only do this if:
|
|
# 1. We're not already about to close the connection.
|
|
# 2. There's no already currently running task(s).
|
|
# 3. There's no data in the output buffer that needs to be sent
|
|
# before we potentially create a new task.
|
|
return not (self.will_close or self.requests or self.total_outbufs_len)
|
|
|
|
def handle_read(self):
|
|
try:
|
|
data = self.recv(self.adj.recv_bytes)
|
|
except socket.error:
|
|
if self.adj.log_socket_errors:
|
|
self.logger.exception("Socket error")
|
|
self.handle_close()
|
|
return
|
|
if data:
|
|
self.last_activity = time.time()
|
|
self.received(data)
|
|
|
|
def received(self, data):
|
|
"""
|
|
Receives input asynchronously and assigns one or more requests to the
|
|
channel.
|
|
"""
|
|
# Preconditions: there's no task(s) already running
|
|
request = self.request
|
|
requests = []
|
|
|
|
if not data:
|
|
return False
|
|
|
|
while data:
|
|
if request is None:
|
|
request = self.parser_class(self.adj)
|
|
n = request.received(data)
|
|
if request.expect_continue and request.headers_finished:
|
|
# guaranteed by parser to be a 1.1 request
|
|
request.expect_continue = False
|
|
if not self.sent_continue:
|
|
# there's no current task, so we don't need to try to
|
|
# lock the outbuf to append to it.
|
|
outbuf_payload = b"HTTP/1.1 100 Continue\r\n\r\n"
|
|
self.outbufs[-1].append(outbuf_payload)
|
|
self.current_outbuf_count += len(outbuf_payload)
|
|
self.total_outbufs_len += len(outbuf_payload)
|
|
self.sent_continue = True
|
|
self._flush_some()
|
|
request.completed = False
|
|
if request.completed:
|
|
# The request (with the body) is ready to use.
|
|
self.request = None
|
|
if not request.empty:
|
|
requests.append(request)
|
|
request = None
|
|
else:
|
|
self.request = request
|
|
if n >= len(data):
|
|
break
|
|
data = data[n:]
|
|
|
|
if requests:
|
|
self.requests = requests
|
|
self.server.add_task(self)
|
|
|
|
return True
|
|
|
|
def _flush_some_if_lockable(self):
|
|
# Since our task may be appending to the outbuf, we try to acquire
|
|
# the lock, but we don't block if we can't.
|
|
if self.outbuf_lock.acquire(False):
|
|
try:
|
|
self._flush_some()
|
|
|
|
if self.total_outbufs_len < self.adj.outbuf_high_watermark:
|
|
self.outbuf_lock.notify()
|
|
finally:
|
|
self.outbuf_lock.release()
|
|
|
|
def _flush_some(self):
|
|
# Send as much data as possible to our client
|
|
|
|
sent = 0
|
|
dobreak = False
|
|
|
|
while True:
|
|
outbuf = self.outbufs[0]
|
|
# use outbuf.__len__ rather than len(outbuf) FBO of not getting
|
|
# OverflowError on 32-bit Python
|
|
outbuflen = outbuf.__len__()
|
|
while outbuflen > 0:
|
|
chunk = outbuf.get(self.sendbuf_len)
|
|
num_sent = self.send(chunk)
|
|
if num_sent:
|
|
outbuf.skip(num_sent, True)
|
|
outbuflen -= num_sent
|
|
sent += num_sent
|
|
self.total_outbufs_len -= num_sent
|
|
else:
|
|
# failed to write anything, break out entirely
|
|
dobreak = True
|
|
break
|
|
else:
|
|
# self.outbufs[-1] must always be a writable outbuf
|
|
if len(self.outbufs) > 1:
|
|
toclose = self.outbufs.pop(0)
|
|
try:
|
|
toclose.close()
|
|
except Exception:
|
|
self.logger.exception("Unexpected error when closing an outbuf")
|
|
else:
|
|
# caught up, done flushing for now
|
|
dobreak = True
|
|
|
|
if dobreak:
|
|
break
|
|
|
|
if sent:
|
|
self.last_activity = time.time()
|
|
return True
|
|
|
|
return False
|
|
|
|
def handle_close(self):
|
|
with self.outbuf_lock:
|
|
for outbuf in self.outbufs:
|
|
try:
|
|
outbuf.close()
|
|
except Exception:
|
|
self.logger.exception(
|
|
"Unknown exception while trying to close outbuf"
|
|
)
|
|
self.total_outbufs_len = 0
|
|
self.connected = False
|
|
self.outbuf_lock.notify()
|
|
wasyncore.dispatcher.close(self)
|
|
|
|
def add_channel(self, map=None):
|
|
"""See wasyncore.dispatcher
|
|
|
|
This hook keeps track of opened channels.
|
|
"""
|
|
wasyncore.dispatcher.add_channel(self, map)
|
|
self.server.active_channels[self._fileno] = self
|
|
|
|
def del_channel(self, map=None):
|
|
"""See wasyncore.dispatcher
|
|
|
|
This hook keeps track of closed channels.
|
|
"""
|
|
fd = self._fileno # next line sets this to None
|
|
wasyncore.dispatcher.del_channel(self, map)
|
|
ac = self.server.active_channels
|
|
if fd in ac:
|
|
del ac[fd]
|
|
|
|
#
|
|
# SYNCHRONOUS METHODS
|
|
#
|
|
|
|
def write_soon(self, data):
|
|
if not self.connected:
|
|
# if the socket is closed then interrupt the task so that it
|
|
# can cleanup possibly before the app_iter is exhausted
|
|
raise ClientDisconnected
|
|
if data:
|
|
# the async mainloop might be popping data off outbuf; we can
|
|
# block here waiting for it because we're in a task thread
|
|
with self.outbuf_lock:
|
|
self._flush_outbufs_below_high_watermark()
|
|
if not self.connected:
|
|
raise ClientDisconnected
|
|
num_bytes = len(data)
|
|
if data.__class__ is ReadOnlyFileBasedBuffer:
|
|
# they used wsgi.file_wrapper
|
|
self.outbufs.append(data)
|
|
nextbuf = OverflowableBuffer(self.adj.outbuf_overflow)
|
|
self.outbufs.append(nextbuf)
|
|
self.current_outbuf_count = 0
|
|
else:
|
|
if self.current_outbuf_count > self.adj.outbuf_high_watermark:
|
|
# rotate to a new buffer if the current buffer has hit
|
|
# the watermark to avoid it growing unbounded
|
|
nextbuf = OverflowableBuffer(self.adj.outbuf_overflow)
|
|
self.outbufs.append(nextbuf)
|
|
self.current_outbuf_count = 0
|
|
self.outbufs[-1].append(data)
|
|
self.current_outbuf_count += num_bytes
|
|
self.total_outbufs_len += num_bytes
|
|
if self.total_outbufs_len >= self.adj.send_bytes:
|
|
self.server.pull_trigger()
|
|
return num_bytes
|
|
return 0
|
|
|
|
def _flush_outbufs_below_high_watermark(self):
|
|
# check first to avoid locking if possible
|
|
if self.total_outbufs_len > self.adj.outbuf_high_watermark:
|
|
with self.outbuf_lock:
|
|
while (
|
|
self.connected
|
|
and self.total_outbufs_len > self.adj.outbuf_high_watermark
|
|
):
|
|
self.server.pull_trigger()
|
|
self.outbuf_lock.wait()
|
|
|
|
def service(self):
|
|
"""Execute all pending requests """
|
|
with self.task_lock:
|
|
while self.requests:
|
|
request = self.requests[0]
|
|
if request.error:
|
|
task = self.error_task_class(self, request)
|
|
else:
|
|
task = self.task_class(self, request)
|
|
try:
|
|
task.service()
|
|
except ClientDisconnected:
|
|
self.logger.info(
|
|
"Client disconnected while serving %s" % task.request.path
|
|
)
|
|
task.close_on_finish = True
|
|
except Exception:
|
|
self.logger.exception(
|
|
"Exception while serving %s" % task.request.path
|
|
)
|
|
if not task.wrote_header:
|
|
if self.adj.expose_tracebacks:
|
|
body = traceback.format_exc()
|
|
else:
|
|
body = (
|
|
"The server encountered an unexpected "
|
|
"internal server error"
|
|
)
|
|
req_version = request.version
|
|
req_headers = request.headers
|
|
request = self.parser_class(self.adj)
|
|
request.error = InternalServerError(body)
|
|
# copy some original request attributes to fulfill
|
|
# HTTP 1.1 requirements
|
|
request.version = req_version
|
|
try:
|
|
request.headers["CONNECTION"] = req_headers["CONNECTION"]
|
|
except KeyError:
|
|
pass
|
|
task = self.error_task_class(self, request)
|
|
try:
|
|
task.service() # must not fail
|
|
except ClientDisconnected:
|
|
task.close_on_finish = True
|
|
else:
|
|
task.close_on_finish = True
|
|
# we cannot allow self.requests to drop to empty til
|
|
# here; otherwise the mainloop gets confused
|
|
if task.close_on_finish:
|
|
self.close_when_flushed = True
|
|
for request in self.requests:
|
|
request.close()
|
|
self.requests = []
|
|
else:
|
|
# before processing a new request, ensure there is not too
|
|
# much data in the outbufs waiting to be flushed
|
|
# NB: currently readable() returns False while we are
|
|
# flushing data so we know no new requests will come in
|
|
# that we need to account for, otherwise it'd be better
|
|
# to do this check at the start of the request instead of
|
|
# at the end to account for consecutive service() calls
|
|
if len(self.requests) > 1:
|
|
self._flush_outbufs_below_high_watermark()
|
|
request = self.requests.pop(0)
|
|
request.close()
|
|
|
|
if self.connected:
|
|
self.server.pull_trigger()
|
|
self.last_activity = time.time()
|
|
|
|
def cancel(self):
|
|
""" Cancels all pending / active requests """
|
|
self.will_close = True
|
|
self.connected = False
|
|
self.last_activity = time.time()
|
|
self.requests = []
|