partition_handler.py

#!/usr/bin/python

from gevent import monkey
monkey.patch_all()
import logging
import gevent
from gevent.coros import BoundedSemaphore
from kafka import KafkaClient, KeyedProducer, SimpleConsumer, common
from uveserver import UVEServer
import os
import json
import copy
import traceback
import uuid
import struct
import socket
import discoveryclient.client as client 
from pysandesh.util import UTCTimestampUsec
import select
import redis
from collections import namedtuple

PartInfo = namedtuple("PartInfo",["ip_address","instance_id","acq_time","port"])

def sse_pack(d):
    """Pack data in SSE format"""
    buffer = ''
    for k in ['event','data']:
        if k in d.keys():
            buffer += '%s: %s\n' % (k, d[k])
    return buffer + '\n'

class UveCacheProcessor(object):
    def __init__(self, logger, rpass):
        self._logger = logger
        self._rpass = rpass
        self._partkeys = {}
        self._typekeys = {}
        self._uvedb = {} 
        self._agp = {}

    def update_agp(self, agp):
        self._agp = agp

    def get_cache_list(self, tables, filters, patterns, keysonly):
        if not tables:
            tables = self._uvedb.keys()

        filters = filters or {}
        tfilter = filters.get('cfilt')
        ackfilter = filters.get('ackfilt')
        uve_list = {}
        try:
            tqual = {}
            tfilter = tfilter or {}

            # Build a per-table set of all keys matching tfilter
            for typ in tfilter:
                for table in tables:
                    if not table in tqual:
                        tqual[table] = set()
                    if typ in self._typekeys:
                        if table in self._typekeys[typ]:
                            tqual[table].update(self._typekeys[typ][table])

            for table in tables:
                if not table in self._uvedb:
                    continue  
                barekeys = set()
                for bk in self._uvedb[table].keys():
                    if len(tfilter) != 0:
                        if not bk in tqual[table]:
                            continue
                    if patterns:
                        kfilter_match = False
                        for pattern in patterns:
                            if pattern.match(bk):
                                kfilter_match = True
                                break
                        if not kfilter_match:
                            continue
                    barekeys.add(bk)
                    
                brsp = self._get_uve_content(table, barekeys,\
                        tfilter, ackfilter, keysonly)
                if len(brsp) != 0:
                    if keysonly:
                        uve_list[table] = set(brsp.keys())
                    else:
                        uve_list[table] = brsp
        except Exception as ex:
            template = "Exception {0} in uve list proc. Arguments:\n{1!r}"
            messag = template.format(type(ex).__name__, ex.args)
            self._logger.error("%s : traceback %s" % \
                              (messag, traceback.format_exc()))
        return uve_list

    def _get_uve_content(self, table, barekeys, tfilter, ackfilter, keysonly):
        brsp = {}
        uveparts = {}
        for barekey in barekeys:
            part = self._uvedb[table][barekey]["__SOURCE__"]["partition"]
            if not part in uveparts:
                uveparts[part] = set()
            uveparts[part].add(barekey)
        
        for pkey,pvalue in uveparts.iteritems():
            pi = self._agp[pkey]
            lredis = redis.StrictRedis(
                    host=pi.ip_address, 
                    port=pi.port,
                    password=self._rpass,
                    db=7, socket_timeout=90)
            ppe = lredis.pipeline()
            luves = list(uveparts[pkey])
            for elem in luves:
                if len(tfilter) != 0:
                    ltypes = tfilter.keys()
                    ppe.hmget("AGPARTVALUES:%s:%d:%s:%s" % \
                        (pi.instance_id, pkey, table, elem),
                        *ltypes)
                else:
                    ppe.hgetall("AGPARTVALUES:%s:%d:%s:%s" % \
                        (pi.instance_id, pkey, table, elem))
            pperes = ppe.execute()
            for uidx in range(0,len(luves)):
                uvestruct = {}
                if len(tfilter) != 0:
                    for tidx in range(0,len(ltypes)):
                        if not pperes[uidx][tidx]:
                            continue
                        afilter_list = tfilter[ltypes[tidx]]
                        ppeval = json.loads(pperes[uidx][tidx])
                        if len(afilter_list) == 0:
                            uvestruct[ltypes[tidx]] = ppeval
                        else:      
                            for akey, aval in ppeval.iteritems():
                                if akey not in afilter_list:
                                    continue
                                else:
                                    if not ltypes[tidx] in uvestruct:
                                        uvestruct[ltypes[tidx]] = {}
                                    uvestruct[ltypes[tidx]][akey] = aval
                else:
                    for tk,tv in pperes[uidx].iteritems():
                        uvestruct[tk] = json.loads(tv)

                if ackfilter is not None:
                    if "UVEAlarms" in uvestruct and \
                            "alarms" in uvestruct["UVEAlarms"]:
                        alarms = []
                        for alarm in uvestruct["UVEAlarms"]["alarms"]:
                            ack = "false"
                            if "ack" in alarm:
                                if alarm["ack"]:
                                    ack = "true"
                                else:
                                    ack = "false"
                            if ack == ackfilter:
                                alarms.append(alarm)
                        if not len(alarms):
                            del uvestruct["UVEAlarms"]
                        else:
                            uvestruct["UVEAlarms"]["alarms"] = alarms

                if len(uvestruct) != 0: 
                    if keysonly:
                        brsp[luves[uidx]] = None
                    else:
                        brsp[luves[uidx]] = uvestruct
        return brsp
      
    def get_cache_uve(self, key, filters):
        rsp = {}
        try:
            filters = filters or {}
            tfilter = filters.get('cfilt')
            tfilter = tfilter or {}
            ackfilter = filters.get('ackfilt')

            barekey = key.split(":",1)[1]
            table = key.split(":",1)[0]
             
            if table not in self._uvedb:
                return rsp
            if barekey not in self._uvedb[table]:
                return rsp
            
            brsp = self._get_uve_content(table, set([barekey]),\
                    tfilter, ackfilter, False)
            if barekey in brsp:
                rsp = brsp[barekey]

        except Exception as ex:
            template = "Exception {0} in uve cache proc. Arguments:\n{1!r}"
            messag = template.format(type(ex).__name__, ex.args)
            self._logger.error("%s : traceback %s" % \
                              (messag, traceback.format_exc()))
        return rsp

    def store_uve(self, partno, pi, key, typ, value):
        barekey = key.split(":",1)[1]
        table = key.split(":",1)[0]

        if partno not in self._partkeys:
            self._partkeys[partno] = set()

        self._partkeys[partno].add(key)

        if table not in self._uvedb:
            self._uvedb[table] = {}
        if barekey not in self._uvedb[table]:
            self._uvedb[table][barekey] = {}

        if typ is None:
            # delete the entire UVE
            self._partkeys[partno].remove("%s:%s" % \
                (table, barekey))
            for typ1 in self._typekeys.keys():
                if table in self._typekeys[typ1]:
                    if barekey in self._typekeys[typ1][table]:
                        self._typekeys[typ1][table].remove(barekey)
                    if len(self._typekeys[typ1][table]) == 0:
                        del self._typekeys[typ1][table]
            del self._uvedb[table][barekey]
        else:
            if not typ in self._typekeys:
                self._typekeys[typ] = {}
            if not typ in self._uvedb[table][barekey]:
                self._uvedb[table][barekey][typ] = None
            if value is None:
                # remove one type of this UVE
                del self._uvedb[table][barekey][typ]
                if table in self._typekeys[typ]:
                    if barekey in self._typekeys[typ][table]:
                        self._typekeys[typ][table].remove(barekey)
                    if len(self._typekeys[typ][table]) == 0:
                        del self._typekeys[typ][table]
            else:
                self._uvedb[table][barekey][typ] = value
                if not table in self._typekeys[typ]:
                    self._typekeys[typ][table] = set()
                self._typekeys[typ][table].add(barekey)
            self._uvedb[table][barekey]["__SOURCE__"] = \
                    {'instance_id':pi.instance_id, 'ip_address':pi.ip_address, \
                     'partition':partno}

    def clear_partition(self, partno, clear_cb):

        if partno not in self._partkeys:
            self._partkeys[partno] = set()
            return

        for key in self._partkeys[partno]:
            barekey = key.split(":",1)[1]
            table = key.split(":",1)[0]

            del self._uvedb[table][barekey]
            
            # Look in the "types" index and remove this UVE
            for tkey in self._typekeys.keys():
                if table in self._typekeys[tkey]:
                    if barekey in self._typekeys[tkey][table]:
                        self._typekeys[tkey][table].remove(barekey)
                        if len(self._typekeys[tkey][table]) == 0:
                            del self._typekeys[tkey][table]
                        if len(self._typekeys[tkey]) == 0:
                            del self._typekeys[tkey]
            clear_cb(key) 
        self._partkeys[partno] = set()

class UveStreamPart(gevent.Greenlet):
    def __init__(self, partno, logger, cb, pi, rpass, content = True, 
                tablefilt = None, cfilter = None, patterns = None):
        gevent.Greenlet.__init__(self)
        self._logger = logger
        self._cb = cb
        self._pi = pi
        self._partno = partno
        # We need to keep track of UVE contents only for streaming case
        self._content = content
        self._rpass = rpass
        self._tablefilt = None
        if tablefilt:
            self._tablefilt = set(tablefilt)
        self._cfilter = None
        if cfilter:
            self._cfilter = set(cfilter.keys())
        self._patterns = patterns

    def syncpart(self, redish):
        inst = self._pi.instance_id
        part = self._partno
        keys = list(redish.smembers("AGPARTKEYS:%s:%d" % (inst, part)))
        ppe = redish.pipeline()
        lkeys = []
        for key in keys:
            table, barekey = key.split(":",1)
            if self._tablefilt:
                if not table in self._tablefilt:
                    continue
            if self._patterns:
                kfilter_match = False
                for pattern in self._patterns:
                    if pattern.match(barekey):
                        kfilter_match = True
                        break
                if not kfilter_match:
                    continue
            lkeys.append(key)
            # We need to load full UVE contents for streaming case
            # For DBCache case, we only need the struct types
            if self._content:
                ppe.hgetall("AGPARTVALUES:%s:%d:%s" % (inst, part, key))
            else:
                ppe.hkeys("AGPARTVALUES:%s:%d:%s" % (inst, part, key))
        pperes = ppe.execute()
        idx=0
        for res in pperes:
            if self._content:
                for tk,tv in res.iteritems():
                    if self._cfilter:
                        if not tk in self._cfilter:
                            continue
                    self._cb(self._partno, self._pi, lkeys[idx], tk, json.loads(tv))
            else:
                for telem in res:
                    if self._cfilter:
                        if not telem in self._cfilter:
                            continue
                    self._cb(self._partno, self._pi, lkeys[idx], telem, {})

            idx += 1
        
    def _run(self):
        lredis = None
        pb = None
        pause = False
        while True:
            try:
                if pause:
                    gevent.sleep(2)
                    pause = False
                lredis = redis.StrictRedis(
                        host=self._pi.ip_address,
                        port=self._pi.port,
                        password=self._rpass,
                        db=7, socket_timeout=90)
                pb = lredis.pubsub()
                inst = self._pi.instance_id
                part = self._partno
                pb.subscribe('AGPARTPUB:%s:%d' % (inst, part))
                self.syncpart(lredis)
                for message in pb.listen():
                    if message["type"] != "message":
                        continue
                    dataline = message["data"]
                    try:
                        elems = json.loads(dataline)
                    except:
                        self._logger.error("AggUVE Parsing failed: %s" % str(message))
                        continue
                    else:
                         self._logger.info("AggUVE loading: %s" % str(elems))
                    if self._content:
                        ppe = lredis.pipeline()
                    lelems = []
                    for elem in elems:
                        table, barekey = elem["key"].split(":",1)
                        if self._tablefilt:
                            if not table in self._tablefilt:
                                continue
                        if self._patterns:
                            kfilter_match = False
                            for pattern in self._patterns:
                                if pattern.match(barekey):
                                    kfilter_match = True
                                    break
                            if not kfilter_match:
                                continue
                        if elem["type"] and self._cfilter:
                            if not elem["type"] in self._cfilter:
                                continue
                        lelems.append(elem)
                        if self._content:
                            # This UVE was deleted
                            if elem["type"] is None:
                                ppe.exists("AGPARTVALUES:%s:%d:%s" % \
                                    (inst, part, elem["key"]))
                            else:
                                ppe.hget("AGPARTVALUES:%s:%d:%s" % \
                                    (inst, part, elem["key"]), elem["type"])

                    # We need to execute this pipeline read only if we are
                    # keeping track of UVE contents (streaming case)
                    if self._content:
                        pperes = ppe.execute()
                    idx = 0
                    for elem in lelems:

                        key = elem["key"]
                        typ = elem["type"]
                        vdata = None

                        if not typ is None:
                            if self._content:
                                vjson = pperes[idx]
                                if vjson is None:
                                    vdata = None
                                else:
                                    vdata = json.loads(vjson)
                            else:
                                vdata = {}

                        self._cb(self._partno, self._pi, key, typ, vdata)
                        idx += 1

            except gevent.GreenletExit:
                break
            except Exception as ex:
                template = "Exception {0} in uve stream proc. Arguments:\n{1!r}"
                messag = template.format(type(ex).__name__, ex.args)
                self._logger.error("%s : traceback %s" % \
                                  (messag, traceback.format_exc()))
                lredis = None
                if pb is not None:
                    pb.close()
                    pb = None
                    pause = True
        return None

class UveStreamer(gevent.Greenlet):
    def __init__(self, logger, q, rfile, agp_cb, rpass,\
            tablefilt = None, cfilter = None, patterns = None,
            USP_class = UveStreamPart):
        gevent.Greenlet.__init__(self)
        self._logger = logger
        self._q = q
        self._rfile = rfile
        self._agp_cb = agp_cb
        self._agp = {}
        self._parts = {}
        self._rpass = rpass
        self._ccb = None
        self._uvedbcache = UveCacheProcessor(self._logger, rpass)
        self._USP_class = USP_class
        self._tablefilt = tablefilt
        self._cfilter = cfilter
        self._patterns = patterns

    def get_uve(self, key, filters=None):
        return False, self._uvedbcache.get_cache_uve(key, filters)

    def get_uve_list(self, utab, filters, patterns, keysonly = True):
        return self._uvedbcache.get_cache_list(utab, filters, patterns, keysonly)

    def clear_callback(self, key):
        if self._q:
            dt = {'key':key, 'type':None}
            msg = {'event': 'update', 'data':json.dumps(dt)}
            self._q.put(sse_pack(msg))

    def partition_callback(self, partition, pi, key, type, value):
        # gevent is non-premptive; we don't need locks
        if self._q:
            dt = {'key':key, 'type':type}
            if not type is None:
                dt['value'] = value
            msg = {'event': 'update', 'data':json.dumps(dt)}
            self._q.put(sse_pack(msg))
            # If this stream is being used for SSE, we have the UVE value,
            # but do not need to report it to the cache
            if not value is None:
                value = {}

        self._uvedbcache.store_uve(partition, pi, key, type, value)
        
    def set_cleanup_callback(self, cb):
        self._ccb = cb

    def _run(self):
        inputs = [ self._rfile ]
        outputs = [ ]
        if self._q:
            msg = {'event': 'init', 'data':json.dumps(None)}
            self._q.put(sse_pack(msg))
        self._logger.error("Starting UveStreamer")
        while True:
            try:
                if self._rfile is not None:
                    readable, writable, exceptional = \
                        select.select(inputs, outputs, inputs, 1)
                    if (readable or writable or exceptional):
                        break
                else:
                    gevent.sleep(1)
                newagp = self._agp_cb()
                set_new, set_old = set(newagp.keys()), set(self._agp.keys())
                intersect = set_new.intersection(set_old)
                # deleted parts
                for elem in set_old - intersect:
                    self.partition_stop(elem)
                    self._uvedbcache.clear_partition(elem, self.clear_callback)
                # new parts
                for elem in set_new - intersect:
                    self._uvedbcache.clear_partition(elem, self.clear_callback)
                    self.partition_start(elem, newagp[elem])
                # changed parts
                for elem in intersect:
                    if self._agp[elem] != newagp[elem]:
                        self.partition_stop(elem)
                        self._uvedbcache.clear_partition(elem, self.clear_callback)
                        self.partition_start(elem, newagp[elem])
                self._agp = copy.deepcopy(newagp)
                self._uvedbcache.update_agp(self._agp)
            except gevent.GreenletExit:
                break
        self._logger.error("Stopping UveStreamer")
        for part, pi in self._agp.iteritems():
            self.partition_stop(part)
            self._uvedbcache.clear_partition(elem, self.clear_callback)
        if self._q:
            msg = {'event': 'stop', 'data':json.dumps(None)}
            self._q.put(sse_pack(msg))
        if callable(self._ccb):
            self._ccb(self) #remove myself

    def partition_start(self, partno, pi):
        self._logger.error("Starting agguve part %d using %s" % (partno, pi))
        # If we are doing streaming, full UVE contents are needed
        # Otherwise, we only need key/type information for DBCache case
        if self._q:
            content = True
        else:
            content = False
        self._parts[partno] = self._USP_class(partno, self._logger,
            self.partition_callback, pi, self._rpass, content,
            self._tablefilt, self._cfilter, self._patterns)
        self._parts[partno].start()

    def partition_stop(self, partno):
        self._logger.error("Stopping agguve part %d" % partno)
        self._parts[partno].kill()
        del self._parts[partno]
            
class PartitionHandler(gevent.Greenlet):
    def __init__(self, brokers, group, topic, logger, limit):
        gevent.Greenlet.__init__(self)
        self._brokers = brokers
        self._group = group
        self._topic = topic
        self._logger = logger
        self._limit = limit
        self._uvedb = {}
        self._partoffset = 0
        self._kfk = None

    def msg_handler(self, mlist):
        self._logger.info("%s Reading %s" % (self._topic, str(mlist)))
        return True

    def _run(self):
	pcount = 0
        pause = False
        while True:
            try:
                if pause:
                    gevent.sleep(2)
                    pause = False
                self._logger.error("New KafkaClient %s" % self._topic)
                self._kfk = KafkaClient(self._brokers , "kc-" + self._topic)
                try:
                    consumer = SimpleConsumer(self._kfk, self._group, self._topic, buffer_size = 4096*4, max_buffer_size=4096*32)
                    #except:
                except Exception as ex:
                    template = "Consumer Failure {0} occured. Arguments:\n{1!r}"
                    messag = template.format(type(ex).__name__, ex.args)
                    self._logger.error("Error: %s trace %s" % \
                        (messag, traceback.format_exc()))
                    raise RuntimeError(messag)

                self._logger.error("Starting %s" % self._topic)

                # Find the offset of the last message that has been queued
                consumer.seek(-1,2)
                try:
                    mi = consumer.get_message(timeout=0.1)
                    consumer.commit()
                except common.OffsetOutOfRangeError:
                    mi = None
                #import pdb; pdb.set_trace()
                self._logger.info("Last Queued for %s is %s" % \
                                  (self._topic,str(mi)))

                # start reading from last previously processed message
                if mi != None:
                    consumer.seek(-1,1)
                else:
                    consumer.seek(0,0)

                if self._limit:
                    raise gevent.GreenletExit

                while True:
                    try:
                        mlist = consumer.get_messages(10,timeout=0.5)
                        if not self.msg_handler(mlist):
                            raise gevent.GreenletExit
                        consumer.commit()
                        pcount += len(mlist) 
                    except TypeError as ex:
                        self._logger.error("Type Error: %s trace %s" % \
                                (str(ex.args), traceback.format_exc()))
                        gevent.sleep(0.1)
                    except common.FailedPayloadsError as ex:
                        self._logger.error("Payload Error: %s" %  str(ex.args))
                        gevent.sleep(0.1)
            except gevent.GreenletExit:
                break
            except AssertionError as ex:
                self._partoffset = ex
                break
            except Exception as ex:
                template = "An exception of type {0} occured. Arguments:\n{1!r}"
                messag = template.format(type(ex).__name__, ex.args)
                self._logger.error("%s : traceback %s" % \
                                  (messag, traceback.format_exc()))
                self.stop_partition()
                pause = True

        self._logger.error("Stopping %s pcount %d" % (self._topic, pcount))
        partdb = self.stop_partition()
        return self._partoffset, partdb

class UveStreamProc(PartitionHandler):
    # Arguments:
    #
    #  brokers   : broker list for kafka bootstrap
    #  partition : partition number
    #  uve_topic : Topic to consume
    #  logger    : logging object to use  
    #  callback  : Callback function for reporting the set of the UVEs
    #              that may have changed for a given notification
    #  rsc       : Callback function to check on collector status
    #              and get sync contents for new collectors
    #  aginst    : instance_id of alarmgen
    #  rport     : redis server port
    #  disc      : discovery client to publish to
    def __init__(self, brokers, partition, uve_topic, logger, callback,
            host_ip, rsc, aginst, rport, group="-workers"):
        super(UveStreamProc, self).__init__(brokers, group, 
            uve_topic, logger, False)
        self._uvedb = {}
        self._uvein = {}
        self._callback = callback
        self._partno = partition
        self._host_ip = host_ip
        self._ip_code, = struct.unpack('>I', socket.inet_pton(
                                        socket.AF_INET, host_ip))
        self.disc_rset = set()
        self._resource_cb = rsc
        self._aginst = aginst
        self._acq_time = UTCTimestampUsec() 
        self._up = True
        self._rport = rport

    def reset_acq_time(self):
        self._acq_time = UTCTimestampUsec()

    def acq_time(self):
        return self._acq_time

    def resource_check(self, msgs):
        '''
        This function compares the known collectors with the
        list from discovery, and syncs UVE keys accordingly
        '''
        newset , coll_delete, chg_res = self._resource_cb(self._partno, self.disc_rset, msgs)
        for coll in coll_delete:
            self._logger.error("Part %d lost collector %s" % (self._partno, coll))
            self.stop_partition(coll)
        if len(chg_res):
            self.start_partition(chg_res)
        self.disc_rset = newset
        
    def stop_partition(self, kcoll=None):
        clist = []
        if not kcoll:
            clist = self._uvedb.keys()
        else:
            clist = [kcoll]
        self._logger.error("Stopping part %d collectors %s" % \
                (self._partno,clist))

        partdb = {}
        chg = {}
        for coll in clist:
            partdb[coll] = {}
            for gen in self._uvedb[coll].keys():
                partdb[coll][gen] = {}
                for tab in self._uvedb[coll][gen].keys():
                    for rkey in self._uvedb[coll][gen][tab].keys():
                        uk = tab + ":" + rkey
                        chg[uk] = None
                        partdb[coll][gen][uk] = \
                            set(self._uvedb[coll][gen][tab][rkey].keys())
                        
            del self._uvedb[coll]
        self._logger.error("Stopping part %d UVEs %s" % \
                (self._partno,str(chg.keys())))
        if kcoll:
            self._callback(self._partno, chg)
        else:
            # If all collectors are being cleared, clear resoures too
            self.disc_rset = set()
            self._up = False

        return partdb

    def start_partition(self, cbdb):
        ''' This function loads the initial UVE database.
            for the partition
        '''
        self._up = True
        self._logger.error("Starting part %d collectors %s" % \
                (self._partno, str(cbdb.keys())))
        uves  = {}
        for kcoll,coll in cbdb.iteritems():
            self._uvedb[kcoll] = {}
            for kgen,gen in coll.iteritems():
                self._uvedb[kcoll][kgen] = {}
                for kk in gen.keys():
                    tabl = kk.split(":",1)
                    tab = tabl[0]
                    rkey = tabl[1]
                    if not tab in self._uvedb[kcoll][kgen]:
                        self._uvedb[kcoll][kgen][tab] = {}
                    self._uvedb[kcoll][kgen][tab][rkey] = {}

                    if not kk in uves:
                        uves[kk] = None
                    for typ, contents in gen[kk].iteritems():
                        self._uvedb[kcoll][kgen][tab][rkey][typ] = {}
                        self._uvedb[kcoll][kgen][tab][rkey][typ]["c"] = 0
                        self._uvedb[kcoll][kgen][tab][rkey][typ]["u"] = \
                                uuid.uuid1(self._ip_code)
                        # TODO: for loading only specific types:
                        #       uves[kk][typ] = contents
                    
        self._logger.error("Starting part %d UVEs %s" % \
                          (self._partno, str(uves.keys())))
        self._callback(self._partno, uves)

    def contents(self):
        return self._uvedb

    def stats(self):
        ''' Return the UVE incoming stats collected over 
            the last time period for this partition 
            Also, the stats should be cleared to prepare
            for the next period of collection.
        '''
        ret_in  = copy.deepcopy(self._uvein)
        self._uvein = {}
        return ret_in

    def msg_handler(self, mlist):
        self.resource_check(mlist)
        for mm in mlist:
            if mm is None:
                continue
            self._logger.debug("%s Reading offset %d" % \
                    (self._topic, mm.offset))
            if not self.msg_handler_single(mm):
                self._logger.info("%s could not handle %s" % \
                    (self._topic, str(mm)))
                return False
        return True

    def msg_handler_single(self, om):
        self._partoffset = om.offset
        chg = {}
        try:
            params = om.message.key.split("|")
            gen = params[2]
            coll = params[3]
            uv = {}
            uv["type"] = params[1]
            uv["key"] = params[0]
            if om.message.value is None or len(om.message.value) == 0:
                uv["value"] = None
            else:
                uv["value"] = json.loads(om.message.value)

            if not self._uvedb.has_key(coll):
                # This partition is not synced yet.
                # Ignore this message
                self._logger.debug("%s Ignoring UVE %s" % (self._topic, str(om)))
                return True

            if not self._uvedb[coll].has_key(gen):
                self._uvedb[coll][gen] = {}

            tabl = uv["key"].split(":",1)
            tab = tabl[0]
            rkey = tabl[1]
            
            if tab not in self._uvedb[coll][gen]:
                self._uvedb[coll][gen][tab] = {}

            if not rkey in self._uvedb[coll][gen][tab]:
                self._uvedb[coll][gen][tab][rkey] = {}
     
            removed = False

            # uv["type"] and uv["value"] can be decoded as follows:

            # uv["type"] refers to a struct name

            # uv["value"] can be one of the following:
            # - None      # This Type has been deleted.
            # - {}        # The Type has a value, which is 
            #               not available in this message.
            #               (this option is only for raw UVE updates)
            # - {<Value>} # The Value of the Type
            #               (this option is only for agg UVE updates)

            if uv["value"] is None:
                if uv["type"] in self._uvedb[coll][gen][tab][rkey]:
                    del self._uvedb[coll][gen][tab][rkey][uv["type"]]
                if not len(self._uvedb[coll][gen][tab][rkey]):
                    del self._uvedb[coll][gen][tab][rkey]
                removed = True

            if not removed: 
                if uv["type"] in self._uvedb[coll][gen][tab][rkey]:
                    self._uvedb[coll][gen][tab][rkey][uv["type"]]["c"] +=1
                else:
                    self._uvedb[coll][gen][tab][rkey][uv["type"]] = {}
                    self._uvedb[coll][gen][tab][rkey][uv["type"]]["c"] = 1
                    self._uvedb[coll][gen][tab][rkey][uv["type"]]["u"] = \
                        uuid.uuid1(self._ip_code)
            chg[uv["key"]] = { uv["type"] : uv["value"] }

            # Record stats on the input UVE Notifications
            if not self._uvein.has_key(tab):
                self._uvein[tab] = {}
            if not self._uvein[tab].has_key(coll):
                self._uvein[tab][coll] = {}
            if not self._uvein[tab][coll].has_key(gen):
                self._uvein[tab][coll][gen] = {}
            if not self._uvein[tab][coll][gen].has_key(uv["type"]):
                self._uvein[tab][coll][gen][uv["type"]] = 1
            else:
                self._uvein[tab][coll][gen][uv["type"]] += 1

        except Exception as ex:
            template = "An exception of type {0} in uve proc . Arguments:\n{1!r}"
            messag = template.format(type(ex).__name__, ex.args)
            self._logger.info("%s" % messag)
            return False
        else:
            self._callback(self._partno, chg)
        return True
           
if __name__ == '__main__':
    logging.basicConfig(level=logging.INFO,
        format='%(asctime)s %(levelname)s %(message)s')

    workers = {}
    brokers = "localhost:9092,localhost:9093,localhost:9094"
    group = "workers"
    
    kafka = KafkaClient(brokers,str(os.getpid()))
    cons = SimpleConsumer(kafka, group, "ctrl")
    cons.provide_partition_info()
    print "Starting control"
    end_ready = False
    while end_ready == False:
	try:
	    while True:
		part, mmm = cons.get_message(timeout=None)
                mm = mmm.message
		print "Consumed ctrl " + str(mm)
                if mm.value == "start":
                    if workers.has_key(mm.key):
                        print "Dup partition %s" % mm.key
                        raise ValueError
                    else:
                        ph = UveStreamProc(brokers, int(mm.key), "uve-" + mm.key, "alarm-x" + mm.key, logging)
                        ph.start()
                        workers[int(mm.key)] = ph
                elif mm.value == "stop":
                    #import pdb; pdb.set_trace()
                    if workers.has_key(int(mm.key)):
                        ph = workers[int(mm.key)]
                        gevent.kill(ph)
                        res,db = ph.get()
                        print "Returned " + str(res)
                        print "State :"
                        for k,v in db.iteritems():
                            print "%s -> %s" % (k,str(v)) 
                        del workers[int(mm.key)]
                else:
                    end_ready = True
                    cons.commit()
		    gevent.sleep(2)
                    break
	except TypeError:
	    gevent.sleep(0.1)
	except common.FailedPayloadsError as ex:
	    print "Payload Error: " + str(ex.args)
	    gevent.sleep(0.1)
    lw=[]
    for key, value in workers.iteritems():
        gevent.kill(value)
        lw.append(value)

    gevent.joinall(lw)
    print "Ending Consumers"