Mini Shell
# vim: set ts=4 sw=4 expandtab syntax=python:
# pylint: disable=W0622
# Python 3.x updates by Jacob Hipps <jacobh@inmotionhosting.com>
# Copyright (c) 2006 Allan Saddi <allan@saddi.com>
# Copyright (c) 2011 Vladimir Rusinov <vladimir@greenmice.info>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# $Id$
__author__ = 'Allan Saddi <allan@saddi.com>'
__version__ = '$Revision$'
import select
import struct
import socket
import errno
__all__ = ['FCGIApp']
# Constants from the spec.
FCGI_LISTENSOCK_FILENO = 0
FCGI_HEADER_LEN = 8
FCGI_VERSION_1 = 1
FCGI_BEGIN_REQUEST = 1
FCGI_ABORT_REQUEST = 2
FCGI_END_REQUEST = 3
FCGI_PARAMS = 4
FCGI_STDIN = 5
FCGI_STDOUT = 6
FCGI_STDERR = 7
FCGI_DATA = 8
FCGI_GET_VALUES = 9
FCGI_GET_VALUES_RESULT = 10
FCGI_UNKNOWN_TYPE = 11
FCGI_MAXTYPE = FCGI_UNKNOWN_TYPE
FCGI_NULL_REQUEST_ID = 0
FCGI_KEEP_CONN = 1
FCGI_RESPONDER = 1
FCGI_AUTHORIZER = 2
FCGI_FILTER = 3
FCGI_REQUEST_COMPLETE = 0
FCGI_CANT_MPX_CONN = 1
FCGI_OVERLOADED = 2
FCGI_UNKNOWN_ROLE = 3
FCGI_MAX_CONNS = 'FCGI_MAX_CONNS'
FCGI_MAX_REQS = 'FCGI_MAX_REQS'
FCGI_MPXS_CONNS = 'FCGI_MPXS_CONNS'
FCGI_Header = '!BBHHBx'
FCGI_BeginRequestBody = '!HB5x'
FCGI_EndRequestBody = '!LB3x'
FCGI_UnknownTypeBody = '!B7x'
FCGI_BeginRequestBody_LEN = struct.calcsize(FCGI_BeginRequestBody)
FCGI_EndRequestBody_LEN = struct.calcsize(FCGI_EndRequestBody)
FCGI_UnknownTypeBody_LEN = struct.calcsize(FCGI_UnknownTypeBody)
if __debug__:
import time
# Set non-zero to write debug output to a file.
DEBUG = 0
DEBUGLOG = '/tmp/fcgi_app.log'
def _debug(level, msg):
# pylint: disable=W0702
if DEBUG < level:
return
try:
f = open(DEBUGLOG, 'a')
f.write('%sfcgi: %s\n' % (time.ctime()[4:-4], msg))
f.close()
except:
pass
def decode_pair(s, pos=0):
"""
Decodes a name/value pair.
The number of bytes decoded as well as the name/value pair
are returned.
"""
nameLength = ord(s[pos])
if nameLength & 128:
nameLength = struct.unpack('!L', s[pos:pos + 4])[0] & 0x7fffffff
pos += 4
else:
pos += 1
valueLength = ord(s[pos])
if valueLength & 128:
valueLength = struct.unpack('!L', s[pos:pos + 4])[0] & 0x7fffffff
pos += 4
else:
pos += 1
name = s[pos:pos + nameLength]
pos += nameLength
value = s[pos:pos + valueLength]
pos += valueLength
return (pos, (name, value))
def encode_pair(name, value):
"""
Encodes a name/value pair.
The encoded string is returned.
"""
nameLength = len(name)
if nameLength < 128:
s = chr(nameLength)
else:
s = struct.pack('!L', nameLength | 0x80000000)
valueLength = len(value)
if valueLength < 128:
s += chr(valueLength)
else:
s += struct.pack('!L', valueLength | 0x80000000)
return s + name + value
class Record(object):
"""
A FastCGI Record.
Used for encoding/decoding records.
"""
def __init__(self, typ=FCGI_UNKNOWN_TYPE, requestId=FCGI_NULL_REQUEST_ID):
self.version = FCGI_VERSION_1
self.type = typ
self.requestId = requestId
self.contentLength = 0
self.paddingLength = 0
self.contentData = ''
def _recvall(sock, length):
"""
Attempts to receive length bytes from a socket, blocking if necessary.
(Socket may be blocking or non-blocking.)
"""
dataList = []
recvLen = 0
while length:
try:
data = sock.recv(length)
except socket.error as e:
if e[0] == errno.EAGAIN:
select.select([sock], [], [])
continue
else:
raise
if not data: # EOF
break
if isinstance(data, str):
dataList.append(data.encode('utf8'))
else:
dataList.append(data)
dataLen = len(data)
recvLen += dataLen
length -= dataLen
return b''.join(dataList), recvLen
_recvall = staticmethod(_recvall)
def read(self, sock):
"""Read and decode a Record from a socket."""
try:
header, length = self._recvall(sock, FCGI_HEADER_LEN)
except:
raise EOFError
if length < FCGI_HEADER_LEN:
raise EOFError
self.version, self.type, self.requestId, self.contentLength, \
self.paddingLength = struct.unpack(FCGI_Header, header)
if __debug__:
_debug(9, 'read: fd = %d, type = %d, requestId = %d, '
'contentLength = %d' %
(sock.fileno(), self.type, self.requestId,
self.contentLength))
if self.contentLength:
try:
self.contentData, length = self._recvall(sock,
self.contentLength)
except:
raise EOFError
if length < self.contentLength:
raise EOFError
if self.paddingLength:
try:
self._recvall(sock, self.paddingLength)
except:
raise EOFError
def _sendall(sock, data):
"""
Writes data to a socket and does not return until all the data is sent.
"""
length = len(data)
while length:
try:
if isinstance(data, str):
sent = sock.send(data.encode('utf8'))
else:
sent = sock.send(data)
except socket.error as e:
if e[0] == errno.EAGAIN:
select.select([], [sock], [])
continue
else:
raise
data = data[sent:]
length -= sent
_sendall = staticmethod(_sendall)
def write(self, sock):
"""Encode and write a Record to a socket."""
self.paddingLength = - self.contentLength & 7
if __debug__:
_debug(9, 'write: fd = %d, type = %d, requestId = %d, '
'contentLength = %d' %
(sock.fileno(), self.type, self.requestId,
self.contentLength))
header = struct.pack(FCGI_Header, self.version, self.type,
self.requestId, self.contentLength,
self.paddingLength)
self._sendall(sock, header)
if self.contentLength:
self._sendall(sock, self.contentData)
if self.paddingLength:
self._sendall(sock, '\x00' * self.paddingLength)
class FCGIApp(object):
def __init__(self, connect=None, host=None, port=None, filterEnviron=True):
if host is not None:
assert port is not None
connect = (host, port)
self._connect = connect
self._filterEnviron = filterEnviron
def __call__(self, environ, start_response=None):
# For sanity's sake, we don't care about FCGI_MPXS_CONN
# (connection multiplexing). For every request, we obtain a new
# transport socket, perform the request, then discard the socket.
# This is, I believe, how mod_fastcgi does things...
sock = self._getConnection()
# Since this is going to be the only request on this connection,
# set the request ID to 1.
requestId = 1
# Begin the request
rec = Record(FCGI_BEGIN_REQUEST, requestId)
rec.contentData = struct.pack(FCGI_BeginRequestBody, FCGI_RESPONDER, 0)
rec.contentLength = FCGI_BeginRequestBody_LEN
rec.write(sock)
# Filter WSGI environ and send it as FCGI_PARAMS
if self._filterEnviron:
params = self._defaultFilterEnviron(environ)
else:
params = self._lightFilterEnviron(environ)
# TODO: Anything not from environ that needs to be sent also?
self._fcgiParams(sock, requestId, params)
self._fcgiParams(sock, requestId, {})
# Transfer wsgi.input to FCGI_STDIN
#content_length = int(environ.get('CONTENT_LENGTH') or 0)
s = ''
while True:
#chunk_size = min(content_length, 4096)
#s = environ['wsgi.input'].read(chunk_size)
#content_length -= len(s)
rec = Record(FCGI_STDIN, requestId)
rec.contentData = s
rec.contentLength = len(s)
rec.write(sock)
if not s:
break
# Empty FCGI_DATA stream
rec = Record(FCGI_DATA, requestId)
rec.write(sock)
# Main loop. Process FCGI_STDOUT, FCGI_STDERR, FCGI_END_REQUEST
# records from the application.
result = []
err = ''
while True:
inrec = Record()
inrec.read(sock)
if inrec.type == FCGI_STDOUT:
if inrec.contentData:
result.append(inrec.contentData)
else:
# TODO: Should probably be pedantic and no longer
# accept FCGI_STDOUT records?"
pass
elif inrec.type == FCGI_STDERR:
# Simply forward to wsgi.errors
err += inrec.contentData.decode('utf8')
#environ['wsgi.errors'].write(inrec.contentData)
elif inrec.type == FCGI_END_REQUEST:
# TODO: Process appStatus/protocolStatus fields?
break
# Done with this transport socket, close it. (FCGI_KEEP_CONN was not
# set in the FCGI_BEGIN_REQUEST record we sent above. So the
# application is expected to do the same.)
sock.close()
result = b''.join(result)
# Parse response headers from FCGI_STDOUT
status = '200 OK'
headers = []
pos = 0
while True:
eolpos = result.find(b'\n', pos)
if eolpos < 0:
break
line = result[pos:eolpos - 1]
pos = eolpos + 1
# strip in case of CR. NB: This will also strip other
# whitespace...
line = line.strip()
# Empty line signifies end of headers
if not line:
break
# TODO: Better error handling
header, value = line.split(b':', 1)
header = header.strip().lower()
value = value.strip()
if header == 'status':
# Special handling of Status header
status = value
if status.find(b' ') < 0:
# Append a dummy reason phrase if one was not provided
status += ' FCGIApp'
else:
headers.append((header, value))
result = result[pos:]
# Set WSGI status, headers, and return result.
#start_response(status, headers)
#return [result]
return status, headers, result, err
def _getConnection(self):
if self._connect is not None:
# The simple case. Create a socket and connect to the
# application.
if isinstance(self._connect, str):
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
sock.connect(self._connect)
elif hasattr(socket, 'create_connection'):
sock = socket.create_connection(self._connect)
else:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(self._connect)
return sock
# To be done when I have more time...
raise NotImplementedError(
'Launching and managing FastCGI programs not yet implemented')
def _fcgiGetValues(self, sock, vars): # @ReservedAssignment
# Construct FCGI_GET_VALUES record
outrec = Record(FCGI_GET_VALUES)
data = []
for name in vars:
data.append(encode_pair(name, ''))
data = b''.join(data)
outrec.contentData = data
outrec.contentLength = len(data)
outrec.write(sock)
# Await response
inrec = Record()
inrec.read(sock)
result = {}
if inrec.type == FCGI_GET_VALUES_RESULT:
pos = 0
while pos < inrec.contentLength:
pos, (name, value) = decode_pair(inrec.contentData, pos)
result[name] = value
return result
def _fcgiParams(self, sock, requestId, params):
#print params
rec = Record(FCGI_PARAMS, requestId)
data = []
for name, value in params.items():
data.append(encode_pair(name, value))
data = ''.join(data)
rec.contentData = data
rec.contentLength = len(data)
rec.write(sock)
_environPrefixes = ['SERVER_', 'HTTP_', 'REQUEST_', 'REMOTE_', 'PATH_',
'CONTENT_', 'DOCUMENT_', 'SCRIPT_']
_environCopies = ['SCRIPT_NAME', 'QUERY_STRING', 'AUTH_TYPE']
_environRenames = {}
def _defaultFilterEnviron(self, environ):
result = {}
for n in environ.keys():
for p in self._environPrefixes:
if n.startswith(p):
result[n] = environ[n]
if n in self._environCopies:
result[n] = environ[n]
if n in self._environRenames:
result[self._environRenames[n]] = environ[n]
return result
def _lightFilterEnviron(self, environ):
result = {}
for n in environ.keys():
if n.upper() == n:
result[n] = environ[n]
return result
Zerion Mini Shell 1.0