mdserver-web/plugins/sphinx/class/sphinxapi.py

#
# $Id$
#
# Python version of Sphinx searchd client (Python API)
#
# Copyright (c) 2006, Mike Osadnik
# Copyright (c) 2006-2016, Andrew Aksyonoff
# Copyright (c) 2008-2016, Sphinx Technologies Inc
# All rights reserved
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Library General Public License. You should
# have received a copy of the LGPL license along with this program; if you
# did not, you can find it at http://www.gnu.org/
#
# WARNING!!!
#
# As of 2015, we strongly recommend to use either SphinxQL or REST APIs
# rather than the native SphinxAPI.
#
# While both the native SphinxAPI protocol and the existing APIs will
# continue to exist, and perhaps should not even break (too much), exposing
# all the new features via multiple different native API implementations
# is too much of a support complication for us.
#
# That said, you're welcome to overtake the maintenance of any given
# official API, and remove this warning ;)
#

from __future__ import print_function
import sys
import select
import socket
import re
from struct import *

if sys.version_info > (3,):
	long = int
	text_type = str
else:
	text_type = unicode

# known searchd commands
SEARCHD_COMMAND_SEARCH		= 0
SEARCHD_COMMAND_EXCERPT		= 1
SEARCHD_COMMAND_UPDATE		= 2
SEARCHD_COMMAND_KEYWORDS	= 3
SEARCHD_COMMAND_PERSIST		= 4
SEARCHD_COMMAND_STATUS		= 5
SEARCHD_COMMAND_FLUSHATTRS	= 7

# current client-side command implementation versions
VER_COMMAND_SEARCH		= 0x120
VER_COMMAND_EXCERPT		= 0x104
VER_COMMAND_UPDATE		= 0x103
VER_COMMAND_KEYWORDS	= 0x100
VER_COMMAND_STATUS		= 0x101
VER_COMMAND_FLUSHATTRS	= 0x100

# known searchd status codes
SEARCHD_OK				= 0
SEARCHD_ERROR			= 1
SEARCHD_RETRY			= 2
SEARCHD_WARNING			= 3

# known ranking modes (extended2 mode only)
SPH_RANK_PROXIMITY_BM15	= 0 # default mode, phrase proximity major factor and BM15 minor one
SPH_RANK_BM15			= 1 # statistical mode, BM15 ranking only (faster but worse quality)
SPH_RANK_NONE			= 2 # no ranking, all matches get a weight of 1
SPH_RANK_WORDCOUNT		= 3 # simple word-count weighting, rank is a weighted sum of per-field keyword occurence counts
SPH_RANK_PROXIMITY		= 4
SPH_RANK_MATCHANY		= 5
SPH_RANK_FIELDMASK		= 6
SPH_RANK_SPH04			= 7
SPH_RANK_EXPR			= 8
SPH_RANK_TOTAL			= 9

# aliases; to be retired
SPH_RANK_PROXIMITY_BM25	= 0
SPH_RANK_BM25			= 1

# known sort modes
SPH_SORT_RELEVANCE		= 0
SPH_SORT_ATTR_DESC		= 1
SPH_SORT_ATTR_ASC		= 2
SPH_SORT_TIME_SEGMENTS	= 3
SPH_SORT_EXTENDED		= 4

# known filter types
SPH_FILTER_VALUES		= 0
SPH_FILTER_RANGE		= 1
SPH_FILTER_FLOATRANGE	= 2
SPH_FILTER_STRING	= 3
SPH_FILTER_STRING_LIST	= 6

# known attribute types
SPH_ATTR_NONE			= 0
SPH_ATTR_INTEGER		= 1
SPH_ATTR_TIMESTAMP		= 2
SPH_ATTR_ORDINAL		= 3
SPH_ATTR_BOOL			= 4
SPH_ATTR_FLOAT			= 5
SPH_ATTR_BIGINT			= 6
SPH_ATTR_STRING			= 7
SPH_ATTR_FACTORS		= 1001
SPH_ATTR_MULTI			= long(0X40000001)
SPH_ATTR_MULTI64		= long(0X40000002)

SPH_ATTR_TYPES = (SPH_ATTR_NONE,
				  SPH_ATTR_INTEGER,
				  SPH_ATTR_TIMESTAMP,
				  SPH_ATTR_ORDINAL,
				  SPH_ATTR_BOOL,
				  SPH_ATTR_FLOAT,
				  SPH_ATTR_BIGINT,
				  SPH_ATTR_STRING,
				  SPH_ATTR_MULTI,
				  SPH_ATTR_MULTI64)

# known grouping functions
SPH_GROUPBY_DAY	 		= 0
SPH_GROUPBY_WEEK		= 1
SPH_GROUPBY_MONTH		= 2
SPH_GROUPBY_YEAR		= 3
SPH_GROUPBY_ATTR		= 4
SPH_GROUPBY_ATTRPAIR	= 5


class SphinxClient:
	def __init__ (self):
		"""
		Create a new client object, and fill defaults.
		"""
		self._host			= 'localhost'					# searchd host (default is "localhost")
		self._port			= 9312							# searchd port (default is 9312)
		self._path			= None							# searchd unix-domain socket path
		self._socket		= None
		self._offset		= 0								# how much records to seek from result-set start (default is 0)
		self._limit			= 20							# how much records to return from result-set starting at offset (default is 20)
		self._weights		= []							# per-field weights (default is 1 for all fields)
		self._sort			= SPH_SORT_RELEVANCE			# match sorting mode (default is SPH_SORT_RELEVANCE)
		self._sortby		= bytearray()					# attribute to sort by (defualt is "")
		self._min_id		= 0								# min ID to match (default is 0)
		self._max_id		= 0								# max ID to match (default is UINT_MAX)
		self._filters		= []							# search filters
		self._groupby		= bytearray()					# group-by attribute name
		self._groupfunc		= SPH_GROUPBY_DAY				# group-by function (to pre-process group-by attribute value with)
		self._groupsort		= str_bytes('@group desc')		# group-by sorting clause (to sort groups in result set with)
		self._groupdistinct	= bytearray()					# group-by count-distinct attribute
		self._maxmatches	= 1000							# max matches to retrieve
		self._cutoff		= 0								# cutoff to stop searching at
		self._retrycount	= 0								# distributed retry count
		self._retrydelay	= 0								# distributed retry delay
		self._indexweights	= {}							# per-index weights
		self._ranker		= SPH_RANK_PROXIMITY_BM15		# ranking mode
		self._rankexpr		= bytearray()					# ranking expression for SPH_RANK_EXPR
		self._maxquerytime	= 0								# max query time, milliseconds (default is 0, do not limit)
		self._timeout = 1.0									# connection timeout
		self._fieldweights	= {}							# per-field-name weights
		self._select		= str_bytes('*')				# select-list (attributes or expressions, with optional aliases)
		self._query_flags	= SetBit ( 0, 6, True )			# default idf=tfidf_normalized
		self._predictedtime = 0								# per-query max_predicted_time
		self._outerorderby = bytearray()					# outer match sort by
		self._outeroffset = 0								# outer offset
		self._outerlimit = 0								# outer limit
		self._hasouter = False								# sub-select enabled
		self._tokenfilterlibrary = bytearray()						# token_filter plugin library name
		self._tokenfiltername = bytearray()						# token_filter plugin name
		self._tokenfilteropts = bytearray()						# token_filter plugin options
		
		self._error			= ''							# last error message
		self._warning		= ''							# last warning message
		self._reqs			= []							# requests array for multi-query
		
	def __del__ (self):
		if self._socket:
			self._socket.close()


	def GetLastError (self):
		"""
		Get last error message (string).
		"""
		return self._error


	def GetLastWarning (self):
		"""
		Get last warning message (string).
		"""
		return self._warning


	def SetServer (self, host, port = None):
		"""
		Set searchd server host and port.
		"""
		assert(isinstance(host, str))
		if host.startswith('/'):
			self._path = host
			return
		elif host.startswith('unix://'):
			self._path = host[7:]
			return
		self._host = host
		if isinstance(port, int):
			assert(port>0 and port<65536)
			self._port = port
		self._path = None

	def SetConnectTimeout ( self, timeout ):
		"""
		Set connection timeout ( float second )
		"""
		assert (isinstance(timeout, float))
		# set timeout to 0 make connaection non-blocking that is wrong so timeout got clipped to reasonable minimum
		self._timeout = max ( 0.001, timeout )
					
	def _Connect (self):
		"""
		INTERNAL METHOD, DO NOT CALL. Connects to searchd server.
		"""
		if self._socket:
			# we have a socket, but is it still alive?
			sr, sw, _ = select.select ( [self._socket], [self._socket], [], 0 )

			# this is how alive socket should look
			if len(sr)==0 and len(sw)==1:
				return self._socket

			# oops, looks like it was closed, lets reopen
			self._socket.close()
			self._socket = None

		try:
			if self._path:
				af = socket.AF_UNIX
				addr = self._path
				desc = self._path
			else:
				af = socket.AF_INET
				addr = ( self._host, self._port )
				desc = '%s;%s' % addr
			sock = socket.socket ( af, socket.SOCK_STREAM )
			sock.settimeout ( self._timeout )
			sock.connect ( addr )
		except socket.error as msg:
			if sock:
				sock.close()
			self._error = 'connection to %s failed (%s)' % ( desc, msg )
			return

		v = unpack('>L', sock.recv(4))[0]
		if v<1:
			sock.close()
			self._error = 'expected searchd protocol version, got %s' % v
			return

		# all ok, send my version
		sock.send(pack('>L', 1))
		return sock


	def _GetResponse (self, sock, client_ver):
		"""
		INTERNAL METHOD, DO NOT CALL. Gets and checks response packet from searchd server.
		"""
		(status, ver, length) = unpack('>2HL', sock.recv(8))
		response = bytearray()
		left = length
		while left>0:
			chunk = sock.recv(left)
			if chunk:
				response += chunk
				left -= len(chunk)
			else:
				break

		if not self._socket:
			sock.close()

		# check response
		read = len(response)
		if not response or read!=length:
			if length:
				self._error = 'failed to read searchd response (status=%s, ver=%s, len=%s, read=%s)' \
					% (status, ver, length, read)
			else:
				self._error = 'received zero-sized searchd response'
			return None

		# check status
		if status==SEARCHD_WARNING:
			wend = 4 + unpack ( '>L', response[0:4] )[0]
			self._warning = bytes_str(response[4:wend])
			return response[wend:]

		if status==SEARCHD_ERROR:
			self._error = 'searchd error: ' + bytes_str(response[4:])
			return None

		if status==SEARCHD_RETRY:
			self._error = 'temporary searchd error: ' + bytes_str(response[4:])
			return None

		if status!=SEARCHD_OK:
			self._error = 'unknown status code %d' % status
			return None

		# check version
		if ver<client_ver:
			self._warning = 'searchd command v.%d.%d older than client\'s v.%d.%d, some options might not work' \
				% (ver>>8, ver&0xff, client_ver>>8, client_ver&0xff)

		return response


	def _Send ( self, sock, req ):
		"""
		INTERNAL METHOD, DO NOT CALL. send request to searchd server.
		"""
		total = 0
		while True:
			sent = sock.send ( req[total:] )
			if sent<=0:
				break
				
			total = total + sent
		
		return total
		

	def SetLimits (self, offset, limit, maxmatches=0, cutoff=0):
		"""
		Set offset and count into result set, and optionally set max-matches and cutoff limits.
		"""
		assert ( type(offset) in [int,long] and 0<=offset<16777216 )
		assert ( type(limit) in [int,long] and 0<limit<16777216 )
		assert(maxmatches>=0)
		self._offset = offset
		self._limit = limit
		if maxmatches>0:
			self._maxmatches = maxmatches
		if cutoff>=0:
			self._cutoff = cutoff


	def SetMaxQueryTime (self, maxquerytime):
		"""
		Set maximum query time, in milliseconds, per-index. 0 means 'do not limit'.
		"""
		assert(isinstance(maxquerytime,int) and maxquerytime>0)
		self._maxquerytime = maxquerytime


	def SetRankingMode ( self, ranker, rankexpr='' ):
		"""
		Set ranking mode.
		"""
		assert(ranker>=0 and ranker<SPH_RANK_TOTAL)
		self._ranker = ranker
		self._rankexpr = str_bytes(rankexpr)


	def SetSortMode ( self, mode, clause='' ):
		"""
		Set sorting mode.
		"""
		assert ( mode in [SPH_SORT_RELEVANCE, SPH_SORT_ATTR_DESC, SPH_SORT_ATTR_ASC, SPH_SORT_TIME_SEGMENTS, SPH_SORT_EXTENDED] )
		assert ( isinstance ( clause, (str,text_type) ) )
		self._sort = mode
		self._sortby = str_bytes(clause)


	def SetFieldWeights (self, weights):
		"""
		Bind per-field weights by name; expects (name,field_weight) dictionary as argument.
		"""
		assert(isinstance(weights,dict))
		for key,val in list(weights.items()):
			assert(isinstance(key,str))
			AssertUInt32 ( val )
		self._fieldweights = weights


	def SetIndexWeights (self, weights):
		"""
		Bind per-index weights by name; expects (name,index_weight) dictionary as argument.
		"""
		assert(isinstance(weights,dict))
		for key,val in list(weights.items()):
			assert(isinstance(key,str))
			AssertUInt32(val)
		self._indexweights = weights


	def SetIDRange (self, minid, maxid):
		"""
		Set IDs range to match.
		Only match records if document ID is beetwen $min and $max (inclusive).
		"""
		assert(isinstance(minid, (int, long)))
		assert(isinstance(maxid, (int, long)))
		assert(minid<=maxid)
		self._min_id = minid
		self._max_id = maxid


	def SetFilter ( self, attribute, values, exclude=0 ):
		"""
		Set values set filter.
		Only match records where 'attribute' value is in given 'values' set.
		"""
		assert(isinstance(attribute, str))
		assert iter(values)

		for value in values:
			AssertInt32 ( value )

		self._filters.append ( { 'type':SPH_FILTER_VALUES, 'attr':attribute, 'exclude':exclude, 'values':values } )

		
	def SetFilterString ( self, attribute, value, exclude=0 ):
		"""
		Set string filter.
		Only match records where 'attribute' value is equal
		"""
		assert(isinstance(attribute, str))
		assert(isinstance(value, str))

		
		self._filters.append ( { 'type':SPH_FILTER_STRING, 'attr':attribute, 'exclude':exclude, 'value':value } )

		
	def SetFilterStringList ( self, attribute, value, exclude=0 ):
		"""
		Set string list filter.
		"""
		assert(isinstance(attribute, str))
		assert(iter(value))

		for v in value:
			assert(isinstance(v, str))
		
		self._filters.append ( { 'type':SPH_FILTER_STRING_LIST, 'attr':attribute, 'exclude':exclude, 'values':value } )
		

	def SetFilterRange (self, attribute, min_, max_, exclude=0 ):
		"""
		Set range filter.
		Only match records if 'attribute' value is beetwen 'min_' and 'max_' (inclusive).
		"""
		assert(isinstance(attribute, str))
		AssertInt32(min_)
		AssertInt32(max_)
		assert(min_<=max_)

		self._filters.append ( { 'type':SPH_FILTER_RANGE, 'attr':attribute, 'exclude':exclude, 'min':min_, 'max':max_ } )


	def SetFilterFloatRange (self, attribute, min_, max_, exclude=0 ):
		assert(isinstance(attribute,str))
		assert(isinstance(min_,float))
		assert(isinstance(max_,float))
		assert(min_ <= max_)
		self._filters.append ( {'type':SPH_FILTER_FLOATRANGE, 'attr':attribute, 'exclude':exclude, 'min':min_, 'max':max_} ) 


	def SetGroupBy ( self, attribute, func, groupsort='@group desc' ):
		"""
		Set grouping attribute and function.
		"""
		assert(isinstance(attribute, (str,text_type)))
		assert(func in [SPH_GROUPBY_DAY, SPH_GROUPBY_WEEK, SPH_GROUPBY_MONTH, SPH_GROUPBY_YEAR, SPH_GROUPBY_ATTR, SPH_GROUPBY_ATTRPAIR] )
		assert(isinstance(groupsort, (str,text_type)))

		self._groupby = str_bytes(attribute)
		self._groupfunc = func
		self._groupsort = str_bytes(groupsort)


	def SetGroupDistinct (self, attribute):
		assert(isinstance(attribute,(str,text_type)))
		self._groupdistinct = str_bytes(attribute)


	def SetRetries (self, count, delay=0):
		assert(isinstance(count,int) and count>=0)
		assert(isinstance(delay,int) and delay>=0)
		self._retrycount = count
		self._retrydelay = delay


	def SetSelect (self, select):
		assert(isinstance(select, (str,text_type)))
		self._select = str_bytes(select)


	def SetQueryFlag ( self, name, value ):
		known_names = [ "reverse_scan", "sort_method", "max_predicted_time", "boolean_simplify", "idf", "global_idf" ]
		flags = { "reverse_scan":[0, 1], "sort_method":["pq", "kbuffer"],"max_predicted_time":[0], "boolean_simplify":[True, False], "idf":["normalized", "plain", "tfidf_normalized", "tfidf_unnormalized"], "global_idf":[True, False] }
		assert ( name in known_names )
		assert ( value in flags[name] or ( name=="max_predicted_time" and isinstance(value, (int, long)) and value>=0))
		
		if name=="reverse_scan":
			self._query_flags = SetBit ( self._query_flags, 0, value==1 )
		if name=="sort_method":
			self._query_flags = SetBit ( self._query_flags, 1, value=="kbuffer" )
		if name=="max_predicted_time":
			self._query_flags = SetBit ( self._query_flags, 2, value>0 )
			self._predictedtime = int(value)
		if name=="boolean_simplify":
			self._query_flags= SetBit ( self._query_flags, 3, value )
		if name=="idf" and ( value=="plain" or value=="normalized" ) :
			self._query_flags = SetBit ( self._query_flags, 4, value=="plain" )
		if name=="global_idf":
			self._query_flags= SetBit ( self._query_flags, 5, value )
		if name=="idf" and ( value=="tfidf_normalized" or value=="tfidf_unnormalized" ) :
			self._query_flags = SetBit ( self._query_flags, 6, value=="tfidf_normalized" )

	def SetOuterSelect ( self, orderby, offset, limit ):
		assert(isinstance(orderby, (str,text_type)))
		assert(isinstance(offset, (int, long)))
		assert(isinstance(limit, (int, long)))
		assert ( offset>=0 )
		assert ( limit>0 )

		self._outerorderby = str_bytes(orderby)
		self._outeroffset = offset
		self._outerlimit = limit
		self._hasouter = True

	def SetTokenFilter ( self, library, name, opts='' ):
		assert(isinstance(library, str))
		assert(isinstance(name, str))
		assert(isinstance(opts, str))

		self._tokenfilterlibrary = str_bytes(library)
		self._tokenfiltername = str_bytes(name)
		self._tokenfilteropts = str_bytes(opts)
		

	def ResetFilters (self):
		"""
		Clear all filters (for multi-queries).
		"""
		self._filters = []


	def ResetGroupBy (self):
		"""
		Clear groupby settings (for multi-queries).
		"""
		self._groupby = bytearray()
		self._groupfunc = SPH_GROUPBY_DAY
		self._groupsort = str_bytes('@group desc')
		self._groupdistinct = bytearray()

	def ResetQueryFlag (self):
		self._query_flags = SetBit ( 0, 6, True ) # default idf=tfidf_normalized
		self._predictedtime = 0
		
	def ResetOuterSelect (self):
		self._outerorderby = bytearray()
		self._outeroffset = 0
		self._outerlimit = 0
		self._hasouter = False

	def Query (self, query, index='*', comment=''):
		"""
		Connect to searchd server and run given search query.
		Returns None on failure; result set hash on success (see documentation for details).
		"""
		assert(len(self._reqs)==0)
		self.AddQuery(query,index,comment)
		results = self.RunQueries()
		self._reqs = [] # we won't re-run erroneous batch

		if not results or len(results)==0:
			return None
		self._error = results[0]['error']
		self._warning = results[0]['warning']
		if results[0]['status'] == SEARCHD_ERROR:
			return None
		return results[0]


	def AddQuery (self, query, index='*', comment=''):
		"""
		Add query to batch.
		"""
		# build request
		# 6 == match_mode extended2
		req = bytearray()
		req.extend(pack('>5L', self._query_flags, self._offset, self._limit, 6, self._ranker))
		if self._ranker==SPH_RANK_EXPR:
			req.extend(pack('>L', len(self._rankexpr)))
			req.extend(self._rankexpr)
		req.extend(pack('>L', self._sort))
		req.extend(pack('>L', len(self._sortby)))
		req.extend(self._sortby)

		query = str_bytes(query)
		assert(isinstance(query,bytearray))

		req.extend(pack('>L', len(query)))
		req.extend(query)

		req.extend(pack('>L', len(self._weights)))
		for w in self._weights:
			req.extend(pack('>L', w))
		index = str_bytes(index)
		assert(isinstance(index,bytearray))
		req.extend(pack('>L', len(index)))
		req.extend(index)
		req.extend(pack('>L',1)) # id64 range marker
		req.extend(pack('>Q', self._min_id))
		req.extend(pack('>Q', self._max_id))
		
		# filters
		req.extend ( pack ( '>L', len(self._filters) ) )
		for f in self._filters:
			attr = str_bytes(f['attr'])
			req.extend ( pack ( '>L', len(f['attr'])) + attr)
			filtertype = f['type']
			req.extend ( pack ( '>L', filtertype))
			if filtertype == SPH_FILTER_VALUES:
				req.extend ( pack ('>L', len(f['values'])))
				for val in f['values']:
					req.extend ( pack ('>q', val))
			elif filtertype == SPH_FILTER_RANGE:
				req.extend ( pack ('>2q', f['min'], f['max']))
			elif filtertype == SPH_FILTER_FLOATRANGE:
				req.extend ( pack ('>2f', f['min'], f['max']))
			elif filtertype == SPH_FILTER_STRING:
				val = str_bytes(f['value'])
				req.extend ( pack ( '>L', len(val) ) )
				req.extend ( val )
			elif filtertype == SPH_FILTER_STRING_LIST:
				req.extend ( pack ('>L', len(f['values'])))
				for sval in f['values']:
					val = str_bytes( sval )
					req.extend ( pack ( '>L', len(val) ) )
					req.extend(val)
			req.extend ( pack ( '>L', f['exclude'] ) )

		# group-by, max-matches, group-sort
		req.extend ( pack ( '>2L', self._groupfunc, len(self._groupby) ) )
		req.extend ( self._groupby )
		req.extend ( pack ( '>2L', self._maxmatches, len(self._groupsort) ) )
		req.extend ( self._groupsort )
		req.extend ( pack ( '>LLL', self._cutoff, self._retrycount, self._retrydelay))
		req.extend ( pack ( '>L', len(self._groupdistinct)))
		req.extend ( self._groupdistinct)

		# geoanchor point
		req.extend ( pack ('>L', 0) )

		# per-index weights
		req.extend ( pack ('>L',len(self._indexweights)))
		for indx,weight in list(self._indexweights.items()):
			indx = str_bytes(indx)
			req.extend ( pack ('>L',len(indx)) + indx + pack ('>L',weight))

		# max query time
		req.extend ( pack ('>L', self._maxquerytime) )

		# per-field weights
		req.extend ( pack ('>L',len(self._fieldweights) ) )
		for field,weight in list(self._fieldweights.items()):
			field = str_bytes(field)
			req.extend ( pack ('>L',len(field)) + field + pack ('>L',weight) )

		# comment
		comment = str_bytes(comment)
		req.extend ( pack('>L',len(comment)) + comment )

		# attribute overrides
		req.extend ( pack('>L', 0) )

		# select-list
		req.extend ( pack('>L', len(self._select)) )
		req.extend ( self._select )
		if self._predictedtime>0:
			req.extend ( pack('>L', self._predictedtime ) )

		# outer
		req.extend ( pack('>L',len(self._outerorderby)) + self._outerorderby )
		req.extend ( pack ( '>2L', self._outeroffset, self._outerlimit ) )
		if self._hasouter:
			req.extend ( pack('>L', 1) )
		else:
			req.extend ( pack('>L', 0) )

		# token_filter
		req.extend ( pack('>L',len(self._tokenfilterlibrary)) + self._tokenfilterlibrary )
		req.extend ( pack('>L',len(self._tokenfiltername)) + self._tokenfiltername )
		req.extend ( pack('>L',len(self._tokenfilteropts)) + self._tokenfilteropts )
			
		# send query, get response

		self._reqs.append(req)
		return


	def RunQueries (self):
		"""
		Run queries batch.
		Returns None on network IO failure; or an array of result set hashes on success.
		"""
		if len(self._reqs)==0:
			self._error = 'no queries defined, issue AddQuery() first'
			return None

		sock = self._Connect()
		if not sock:
			return None

		req = bytearray()
		for r in self._reqs:
			req.extend(r)
		length = len(req)+8
		req_all = bytearray()
		req_all.extend(pack('>HHLLL', SEARCHD_COMMAND_SEARCH, VER_COMMAND_SEARCH, length, 0, len(self._reqs)))
		req_all.extend(req)
		self._Send ( sock, req_all )

		response = self._GetResponse(sock, VER_COMMAND_SEARCH)
		if not response:
			return None

		nreqs = len(self._reqs)

		# parse response
		max_ = len(response)
		p = 0

		results = []
		for i in range(0,nreqs,1):
			result = {}
			results.append(result)

			result['error'] = ''
			result['warning'] = ''
			status = unpack('>L', response[p:p+4])[0]
			p += 4
			result['status'] = status
			if status != SEARCHD_OK:
				length = unpack('>L', response[p:p+4])[0]
				p += 4
				message = bytes_str(response[p:p+length])
				p += length

				if status == SEARCHD_WARNING:
					result['warning'] = message
				else:
					result['error'] = message
					continue

			# read schema
			fields = []
			attrs = []

			nfields = unpack('>L', response[p:p+4])[0]
			p += 4
			while nfields>0 and p<max_:
				nfields -= 1
				length = unpack('>L', response[p:p+4])[0]
				p += 4
				fields.append(bytes_str(response[p:p+length]))
				p += length

			result['fields'] = fields

			nattrs = unpack('>L', response[p:p+4])[0]
			p += 4
			while nattrs>0 and p<max_:
				nattrs -= 1
				length = unpack('>L', response[p:p+4])[0]
				p += 4
				attr = bytes_str(response[p:p+length])
				p += length
				type_ = unpack('>L', response[p:p+4])[0]
				p += 4
				attrs.append([attr,type_])

			result['attrs'] = attrs

			# read match count
			count = unpack('>L', response[p:p+4])[0]
			p += 4
			id64 = unpack('>L', response[p:p+4])[0]
			p += 4
		
			# read matches
			result['matches'] = []
			while count>0 and p<max_:
				count -= 1
				if id64:
					doc, weight = unpack('>QL', response[p:p+12])
					p += 12
				else:
					doc, weight = unpack('>2L', response[p:p+8])
					p += 8

				match = { 'id':doc, 'weight':weight, 'attrs':{} }
				for i in range(len(attrs)):
					if attrs[i][1] == SPH_ATTR_FLOAT:
						match['attrs'][attrs[i][0]] = unpack('>f', response[p:p+4])[0]
					elif attrs[i][1] == SPH_ATTR_BIGINT:
						match['attrs'][attrs[i][0]] = unpack('>q', response[p:p+8])[0]
						p += 4
					elif attrs[i][1] == SPH_ATTR_STRING:
						slen = unpack('>L', response[p:p+4])[0]
						p += 4
						match['attrs'][attrs[i][0]] = ''
						if slen>0:
							match['attrs'][attrs[i][0]] = bytes_str(response[p:p+slen])
						p += slen-4
					elif attrs[i][1] == SPH_ATTR_FACTORS:
						slen = unpack('>L', response[p:p+4])[0]
						p += 4
						match['attrs'][attrs[i][0]] = ''
						if slen>0:
							match['attrs'][attrs[i][0]] = response[p:p+slen-4]
							p += slen-4
						p -= 4
					elif attrs[i][1] == SPH_ATTR_MULTI:
						match['attrs'][attrs[i][0]] = []
						nvals = unpack('>L', response[p:p+4])[0]
						p += 4
						for n in range(0,nvals,1):
							match['attrs'][attrs[i][0]].append(unpack('>L', response[p:p+4])[0])
							p += 4
						p -= 4
					elif attrs[i][1] == SPH_ATTR_MULTI64:
						match['attrs'][attrs[i][0]] = []
						nvals = unpack('>L', response[p:p+4])[0]
						nvals = nvals/2
						p += 4
						for n in range(0,nvals,1):
							match['attrs'][attrs[i][0]].append(unpack('>q', response[p:p+8])[0])
							p += 8
						p -= 4
					else:
						match['attrs'][attrs[i][0]] = unpack('>L', response[p:p+4])[0]
					p += 4

				result['matches'].append ( match )

			result['total'], result['total_found'], result['time'], words = unpack('>4L', response[p:p+16])

			result['time'] = '%.3f' % (result['time']/1000.0)
			p += 16

			result['words'] = []
			while words>0:
				words -= 1
				length = unpack('>L', response[p:p+4])[0]
				p += 4
				word = bytes_str(response[p:p+length])
				p += length
				docs, hits = unpack('>2L', response[p:p+8])
				p += 8

				result['words'].append({'word':word, 'docs':docs, 'hits':hits})
		
		self._reqs = []
		return results
	

	def BuildExcerpts (self, docs, index, words, opts=None):
		"""
		Connect to searchd server and generate exceprts from given documents.
		"""
		if not opts:
			opts = {}

		assert(isinstance(docs, list))
		assert(isinstance(index, (str,text_type)))
		assert(isinstance(words, (str,text_type)))
		assert(isinstance(opts, dict))

		sock = self._Connect()

		if not sock:
			return None

		# fixup options
		opts.setdefault('before_match', '<b>')
		opts.setdefault('after_match', '</b>')
		opts.setdefault('chunk_separator', ' ... ')
		opts.setdefault('html_strip_mode', 'index')
		opts.setdefault('limit', 256)
		opts.setdefault('limit_passages', 0)
		opts.setdefault('limit_words', 0)
		opts.setdefault('around', 5)
		opts.setdefault('start_passage_id', 1)
		opts.setdefault('passage_boundary', 'none')

		# build request
		# v.1.0 req

		flags = 1 # (remove spaces)
		if opts.get('exact_phrase'):	flags |= 2
		if opts.get('single_passage'):	flags |= 4
		if opts.get('use_boundaries'):	flags |= 8
		if opts.get('weight_order'):	flags |= 16
		if opts.get('query_mode'):		flags |= 32
		if opts.get('force_all_words'):	flags |= 64
		if opts.get('load_files'):		flags |= 128
		if opts.get('allow_empty'):		flags |= 256
		if opts.get('emit_zones'):		flags |= 512
		if opts.get('load_files_scattered'):	flags |= 1024
		
		# mode=0, flags
		req = bytearray()
		req.extend(pack('>2L', 0, flags))

		# req index
		index = str_bytes(index)
		req.extend(pack('>L', len(index)))
		req.extend(index)

		# req words
		words = str_bytes(words)
		req.extend(pack('>L', len(words)))
		req.extend(words)

		# options
		opts_before_match = str_bytes(opts['before_match'])
		req.extend(pack('>L', len(opts_before_match)))
		req.extend(opts_before_match)

		opts_after_match = str_bytes(opts['after_match'])
		req.extend(pack('>L', len(opts_after_match)))
		req.extend(opts_after_match)

		opts_chunk_separator = str_bytes(opts['chunk_separator'])
		req.extend(pack('>L', len(opts_chunk_separator)))
		req.extend(opts_chunk_separator)

		req.extend(pack('>L', int(opts['limit'])))
		req.extend(pack('>L', int(opts['around'])))
		
		req.extend(pack('>L', int(opts['limit_passages'])))
		req.extend(pack('>L', int(opts['limit_words'])))
		req.extend(pack('>L', int(opts['start_passage_id'])))
		opts_html_strip_mode = str_bytes(opts['html_strip_mode'])
		req.extend(pack('>L', len(opts_html_strip_mode)))
		req.extend(opts_html_strip_mode)
		opts_passage_boundary = str_bytes(opts['passage_boundary'])
		req.extend(pack('>L', len(opts_passage_boundary)))
		req.extend(opts_passage_boundary)

		# documents
		req.extend(pack('>L', len(docs)))
		for doc in docs:
			doc = str_bytes(doc)
			req.extend(pack('>L', len(doc)))
			req.extend(doc)

		# send query, get response
		length = len(req)

		# add header
		req_head = bytearray()
		req_head.extend(pack('>2HL', SEARCHD_COMMAND_EXCERPT, VER_COMMAND_EXCERPT, length))
		req_all = req_head + req
		self._Send ( sock, req_all )

		response = self._GetResponse(sock, VER_COMMAND_EXCERPT )
		if not response:
			return []

		# parse response
		pos = 0
		res = []
		rlen = len(response)

		for i in range(len(docs)):
			length = unpack('>L', response[pos:pos+4])[0]
			pos += 4

			if pos+length > rlen:
				self._error = 'incomplete reply'
				return []

			res.append(bytes_str(response[pos:pos+length]))
			pos += length

		return res


	def UpdateAttributes ( self, index, attrs, values, mva=False, ignorenonexistent=False ):
		"""
		Update given attribute values on given documents in given indexes.
		Returns amount of updated documents (0 or more) on success, or -1 on failure.

		'attrs' must be a list of strings.
		'values' must be a dict with int key (document ID) and list of int values (new attribute values).
		optional boolean parameter 'mva' points that there is update of MVA attributes.
		In this case the 'values' must be a dict with int key (document ID) and list of lists of int values
		(new MVA attribute values).
		Optional boolean parameter 'ignorenonexistent' points that the update will silently ignore any warnings about
		trying to update a column which is not exists in current index schema.

		Example:
			res = cl.UpdateAttributes ( 'test1', [ 'group_id', 'date_added' ], { 2:[123,1000000000], 4:[456,1234567890] } )
		"""
		assert ( isinstance ( index, str ) )
		assert ( isinstance ( attrs, list ) )
		assert ( isinstance ( values, dict ) )
		for attr in attrs:
			assert ( isinstance ( attr, str ) )
		for docid, entry in list(values.items()):
			AssertUInt32(docid)
			assert ( isinstance ( entry, list ) )
			assert ( len(attrs)==len(entry) )
			for val in entry:
				if mva:
					assert ( isinstance ( val, list ) )
					for vals in val:
						AssertInt32(vals)
				else:
					AssertInt32(val)

		# build request
		req = bytearray()
		index = str_bytes(index)
		req.extend( pack('>L',len(index)) + index )

		req.extend ( pack('>L',len(attrs)) )
		ignore_absent = 0
		if ignorenonexistent: ignore_absent = 1
		req.extend ( pack('>L', ignore_absent ) )
		mva_attr = 0
		if mva: mva_attr = 1
		for attr in attrs:
			attr = str_bytes(attr)
			req.extend ( pack('>L',len(attr)) + attr )
			req.extend ( pack('>L', mva_attr ) )

		req.extend ( pack('>L',len(values)) )
		for docid, entry in list(values.items()):
			req.extend ( pack('>Q',docid) )
			for val in entry:
				val_len = val
				if mva: val_len = len ( val )
				req.extend ( pack('>L',val_len ) )
				if mva:
					for vals in val:
						req.extend ( pack ('>L',vals) )

		# connect, send query, get response
		sock = self._Connect()
		if not sock:
			return None

		length = len(req)
		req_all = bytearray()
		req_all.extend( pack ( '>2HL', SEARCHD_COMMAND_UPDATE, VER_COMMAND_UPDATE, length ) )
		req_all.extend( req )
		self._Send ( sock, req_all )

		response = self._GetResponse ( sock, VER_COMMAND_UPDATE )
		if not response:
			return -1

		# parse response
		updated = unpack ( '>L', response[0:4] )[0]
		return updated


	def BuildKeywords ( self, query, index, hits ):
		"""
		Connect to searchd server, and generate keywords list for a given query.
		Returns None on failure, or a list of keywords on success.
		"""
		assert ( isinstance ( query, str ) )
		assert ( isinstance ( index, str ) )
		assert ( isinstance ( hits, int ) )

		# build request
		req = bytearray()
		query = str_bytes(query)
		req.extend(pack ( '>L', len(query) ) + query)
		index = str_bytes(index)
		req.extend ( pack ( '>L', len(index) ) + index )
		req.extend ( pack ( '>L', hits ) )

		# connect, send query, get response
		sock = self._Connect()
		if not sock:
			return None

		length = len(req)
		req_all = bytearray()
		req_all.extend(pack ( '>2HL', SEARCHD_COMMAND_KEYWORDS, VER_COMMAND_KEYWORDS, length ))
		req_all.extend(req)
		self._Send ( sock, req_all )

		response = self._GetResponse ( sock, VER_COMMAND_KEYWORDS )
		if not response:
			return None

		# parse response
		res = []

		nwords = unpack ( '>L', response[0:4] )[0]
		p = 4
		max_ = len(response)

		while nwords>0 and p<max_:
			nwords -= 1

			length = unpack ( '>L', response[p:p+4] )[0]
			p += 4
			tokenized = response[p:p+length]
			p += length

			length = unpack ( '>L', response[p:p+4] )[0]
			p += 4
			normalized = response[p:p+length]
			p += length

			entry = { 'tokenized':bytes_str(tokenized), 'normalized':bytes_str(normalized) }
			if hits:
				entry['docs'], entry['hits'] = unpack ( '>2L', response[p:p+8] )
				p += 8

			res.append ( entry )

		if nwords>0 or p>max_:
			self._error = 'incomplete reply'
			return None

		return res

	def Status ( self, session=False ):
		"""
		Get the status
		"""

		# connect, send query, get response
		sock = self._Connect()
		if not sock:
			return None

		sess = 1
		if session:
			sess = 0

		req = pack ( '>2HLL', SEARCHD_COMMAND_STATUS, VER_COMMAND_STATUS, 4, sess )
		self._Send ( sock, req )

		response = self._GetResponse ( sock, VER_COMMAND_STATUS )
		if not response:
			return None

		# parse response
		res = []

		p = 8
		max_ = len(response)

		while p<max_:
			length = unpack ( '>L', response[p:p+4] )[0]
			k = response[p+4:p+length+4]
			p += 4+length
			length = unpack ( '>L', response[p:p+4] )[0]
			v = response[p+4:p+length+4]
			p += 4+length
			res += [[bytes_str(k), bytes_str(v)]]

		return res

	### persistent connections

	def Open(self):
		if self._socket:
			self._error = 'already connected'
			return None
		
		server = self._Connect()
		if not server:
			return None

		# command, command version = 0, body length = 4, body = 1
		request = pack ( '>hhII', SEARCHD_COMMAND_PERSIST, 0, 4, 1 )
		self._Send ( server, request )
		
		self._socket = server
		return True

	def Close(self):
		if not self._socket:
			self._error = 'not connected'
			return
		self._socket.close()
		self._socket = None
	
	def EscapeString(self, string):
		return re.sub(r"([=\(\)|\-!@~\"&/\\\^\$\=\<])", r"\\\1", string)


	def FlushAttributes(self):
		sock = self._Connect()
		if not sock:
			return -1

		request = pack ( '>hhI', SEARCHD_COMMAND_FLUSHATTRS, VER_COMMAND_FLUSHATTRS, 0 ) # cmd, ver, bodylen
		self._Send ( sock, request )

		response = self._GetResponse ( sock, VER_COMMAND_FLUSHATTRS )
		if not response or len(response)!=4:
			self._error = 'unexpected response length'
			return -1

		tag = unpack ( '>L', response[0:4] )[0]
		return tag

def AssertInt32 ( value ):
	assert(isinstance(value, (int, long)))
	assert(value>=-2**32-1 and value<=2**32-1)

def AssertUInt32 ( value ):
	assert(isinstance(value, (int, long)))
	assert(value>=0 and value<=2**32-1)

def SetBit ( flag, bit, on ):
	if on:
		flag += ( 1<<bit )
	else:
		reset = 255 ^ ( 1<<bit )
		flag = flag & reset

	return flag

if sys.version_info > (3,):
	def str_bytes(x):
		return bytearray(x, 'utf-8')
else:
	def str_bytes(x):
		if isinstance(x,unicode):
			return bytearray(x, 'utf-8')
		else:
			return bytearray(x)

def bytes_str(x):
	assert (isinstance(x, bytearray))
	return x.decode('utf-8')
	
#
# $Id$
#