def __init__(self, id = -1, config = None):
self.id = id
self.set_config(config)
# inner data structure
self.input = Input()
self.context_database = ContextDatabase()
self.assorted_context_database = AssortedContextDatabase()
self.output = Output()
self.context_history = ContextHistory()
# instance variables for debugging purposes
self.new_aggregate = None
self.filtered_singles = None
self.data = None
self.average = None
class ContextAggregator(object):
"""database class"""
AGGREGATION_MODE = 0
SINGLE_ONLY_MODE = 1
MAX_TAU = "max_tau"
PM = "propagation_mode"
defaults = {MAX_TAU:0, PM:AGGREGATION_MODE}
def is_single_only_mode(self):
return self.configuration(ContextAggregator.PM) == ContextAggregator.SINGLE_ONLY_MODE
def is_aggregation_mode(self):
return self.configuration(ContextAggregator.PM) == ContextAggregator.AGGREGATION_MODE
#
# Initialization and Reset
#
def __init__(self, id = -1, config = None):
self.id = id
self.set_config(config)
# inner data structure
self.input = Input()
self.context_database = ContextDatabase()
self.assorted_context_database = AssortedContextDatabase()
self.output = Output()
self.context_history = ContextHistory()
# instance variables for debugging purposes
self.new_aggregate = None
self.filtered_singles = None
self.data = None
self.average = None
def get_data(self):
return self.data
def __reset(self):
self.input.reset()
self.context_database.reset()
self.assorted_context_database.reset()
self.output.reset()
self.context_history.reset()
def reset(self):
"""reset is for garbage collection in multiple data simulation.
This is done for releasing memory for another simulation.
"""
self.__reset()
gc.collect()
#
# Sample
#
def get_sample(self):
return self.configuration("sample")
def get_sample_data(self):
sample = self.get_sample()
if sample is None:
return None # sampled_value = -2 # default value is -1
# [] works as an API
return sample[self.id]
#
# Input
#
def get_input_dictionary(self):
return self.input.dictionary
def initalize_before_iteration(self):
"""initialization is needed for starting execution of dataflow
"""
self.input.reset()
#
# Configuration methods
#
def get_config(self):
return self.config
def set_config(self, config):
self.config = process_default_values(config, ContextAggregator.defaults)
return self.config
def get_current_sample(self):
return self.current_sample
def configuration(self, key):
if key in self.config:
return self.config[key]
else:
return None
#
# Database
#
def set_database(self, singles, aggregates, timestamp = 0):
"""TODO: update information based on the time stamp
"""
self.context_database.set(singles, aggregates, timestamp)
def get_database_singles(self, timestamp=0):
return self.context_database.get_singles(timestamp)
def get_database_aggregates(self, timestamp=0):
return self.context_database.get_aggregates(timestamp)
def get_singles(self, timestamp=0):
return self.context_database.get_singles(timestamp)
#return self.assorted_context_database.get_singles(timestamp)
def get_aggregates(self, timestamp=0):
return self.context_database.get_aggregates(timestamp)
def get_primes(self, timestamp=0):
return self.assorted_context_database.get_primes(timestamp)
def get_non_primes(self, timestamp=0):
return self.assorted_context_database.get_non_primes(timestamp)
def get_selected_non_primes(self, timestamp=0):
return self.assorted_context_database.get_selected_non_primes(timestamp)
def get_new_aggregate(self):
return self.new_aggregate
def get_filtered_singles(self):
return self.filtered_singles
###################################
# STATIC METHODS
###################################
@staticmethod
def create_new_aggregate(contexts, timestamp=0):
"""Given contexts (a list of a set of contexts, create a context that collects all
the information in them)
Things to consider: we pack the single context with Context.SPECIAL_CONTEXT (let's say it as x), because
1. We can recover the aggregate without the x, whenever x is available.
2. We can cover larger aggregate even when x is lost (or unavailable with any reason).
>>> s1 = set([Context(value=1.0, cohorts=[0])])
>>> c1 = set([Context(value=1.0, cohorts=[1,2])])
>>> c = ContextAggregator.create_new_aggregate([c1,s1])
>>> c.value
1.0
>>> c.get_cohorts_as_set() == set([0,1,2])
True
>>> c = ContextAggregator.create_new_aggregate([s1, c1, set(), set()])
>>> c.value
"""
sum = 0.0
elements = set()
for context_set in contexts:
for c in context_set:
sum += c.value * len(c)
elements = elements.union(c.get_cohorts_as_set())
value = sum / len(elements)
c = Context(value=value, cohorts=elements, hopcount=Context.AGGREGATED_CONTEXT, timestamp=timestamp)
return c
@staticmethod
def remove_same_id_singles(singles):
"""
>>> singles = {Context(value=1.0, cohorts={1}, hopcount=1), Context(value=1.0, cohorts={1}, hopcount=2), Context(value=1.0, cohorts={1}, hopcount=3)}
>>> c = ContextAggregator.remove_same_id_singles(singles)
>>> len(c)
1
>>> s = list(c)[0]
>>> s.hopcount == 1
True
"""
# It can happen that the same context with a change in hopcount can exist
singles_dictionary = {}
for s in singles:
key = s.get_id()
if key not in singles_dictionary:
singles_dictionary[key] = []
singles_dictionary[key].append(s)
result = set()
for key, values in singles_dictionary.items():
if len(values) == 1:
result.add(values[0])
else:
result.add(sorted(values, key=lambda m: m.hopcount)[0])
return result
@staticmethod
def remove_same_id_aggregates(aggregates):
"""
>>> aggregates = {Context(value=1.0, cohorts={1,2,3}, hopcount=1), Context(value=1.0, cohorts={1,2,3}, hopcount=2), Context(value=1.0, cohorts={1,2,3}, hopcount=3)}
>>> c = ContextAggregator.remove_same_id_aggregates(aggregates)
>>> len(c)
1
>>> print list(c)[0]
v(1.00):c([1,2,3]):h(1):t(0)
"""
# It can happen that the same context with a change in hopcount can exist
aggr_dictionary = {}
for s in aggregates:
key = frozenset(s.get_cohorts_as_set())
if key in aggr_dictionary:
hopcount = aggr_dictionary[key].hopcount
# only the newest (smallest number) wins
if s.hopcount < hopcount:
aggr_dictionary[key] = s
else:
aggr_dictionary[key] = s
result = set(aggr_dictionary.values())
return result
@staticmethod
def filter_singles_by_hopcount(singles, configuration):
"""Out of many input/stored singles, filter out the singles to send
based on configuration.
"""
max_tau = configuration(ContextAggregator.MAX_TAU)
results = set()
for s in singles:
if s.hopcount == Context.SPECIAL_CONTEXT or 0 <= s.hopcount <= max_tau:
results.add(s)
if configuration("propagate_recovered_singles"):
if s.hopcount == Context.RECOVERED_CONTEXT:
context = copy(s)
context.hopcount = 0
results.add(context)
return results
@staticmethod
def sample(samples=None, timestamp=0):
"""Sampling means read (acuquire) data at timestamp, and create a single context out of the data
"""
#samples = self.get_sample_data()
if samples is None:
return -1, False
else:
#samples = self.config["sample"][self.id]
if type(samples) is tuple:
# the order is important as samples are modified into a tuple to a list
special_flags = samples[1]
samples = samples[0] # now it's list
else:
special_flags = [False] * len(samples)
length = len(samples)
if length > timestamp:
sampled_value = samples[timestamp]
special_flag = special_flags[timestamp]
else:
special_flag = False
#self.current_sample = sampled_value
return sampled_value, special_flag
@staticmethod
def get_score(cohorts, sent_history_as_set):
"""Returns the number of elements cohorts - sent_history_as_set
>>> a = {1,2,3,4}
>>> b = {4,5,6,7}
>>> ContextAggregator.get_score(a, b)
3
"""
return len(cohorts - sent_history_as_set)
@staticmethod
def get_output_from_nps(aggregates, history, neighbors):
"""Find the aggregate that has the largest set of contexts that are not sent to neighbors
>>> a = {Context(value=1.0, cohorts=[1,2,3]), Context(value=1.0, cohorts=[1,2,3,4]), Context(value=1.0, cohorts=[1,2,3,4,5])}
>>> h = {1:[[],[1,3]], 2:[[],[1,3]]}
>>> neighbors = [1,2]
>>> r = ContextAggregator.get_output_from_nps(a, h, neighbors)
>>> same(r[1], [[],[1,2,3,4,5]])
True
"""
if len(aggregates) == 0: return {}
if len(neighbors) == 0: return {}
result = {}
for n in neighbors:
# get the aggregation
sent_history_as_set = set(history[n][1])
scores = {}
for a in aggregates:
cohorts = a.get_cohorts_as_set()
key = str(list(cohorts))
scores[key] = ContextAggregator.get_score(cohorts, sent_history_as_set)
keys = sorted(scores, key=lambda e: -scores[e])
# when sending only one context
if scores[keys[0]] > 0:
winner = eval(keys[0])
result[n] = [[],winner]
else:
result[n] = [[],[]]
return result
#self.context_database.aggregates, self.context_history.get(timestamp), neighbors)
###################################
# DATA FLOW
###################################
def application_disseminate_when_above_average(self, new_aggregate, filtered_singles, timestamp, iteration):
"""Application
Given average, compare the average with the sensor data to create and replace the single context
Side effect: filtered_singles are modified when necessary
"""
average = new_aggregate.value
variation = self.get_data() - average
percentage_variation = abs(variation)/average*100.0
if "threshold" not in self.config:
threshold = sys.maxint
else:
threshold = self.config["threshold"]
if percentage_variation > threshold: # Threshold is 50 as now
context = Context(value=self.get_data(), cohorts=[self.id], hopcount=Context.SPECIAL_CONTEXT, timestamp=timestamp)
print "Weird, diesseminate myself %d %d" % (self.id, iteration)
# it just compares the id and hopcount is ignored in comparison
remove_if_in(context, filtered_singles)
#
# WARINING! Side effect here!
#
filtered_singles.add(context)
# the single context in the db should be updated
self.context_database.update_context_hopcount(self.id, Context.SPECIAL_CONTEXT)
return filtered_singles
def get_new_info(self, singles, filtered_singles, primes, selected_non_primes, timestamp, iteration):
"""Given singles/primes/non_primes return new_info in standard form, and newly created new_aggregates
* singles are needed to make maximal aggregates
* filtered_singles are needed to identify what singles are to sent
new_aggregate is None when there is no new aggregates created
"""
if len(singles) == 1 and primes == set() and selected_non_primes == set(): # there is only one single context
singles = contexts_to_standard(singles)
new_info = add_standards(singles, [[],[]]) # standard operation
new_aggregate = None
else:
# from singles/primes/non_primes get new aggregated contexts
new_aggregate = ContextAggregator.create_new_aggregate(contexts=[singles, primes, selected_non_primes], timestamp=timestamp)
filtered_singles = self.application_disseminate_when_above_average(new_aggregate, filtered_singles, timestamp, iteration)
# we need to generate the new_info in the form of standard
a = contexts_to_standard({new_aggregate})
s = contexts_to_standard(filtered_singles)
new_info = add_standards(a, s)
return new_info, new_aggregate
def set_database_and_return(self, result, new_aggregates, singles, aggregates, primes, non_primes, selected_non_primes, timestamp):
self.new_aggregate = new_aggregates
self.set_database(singles, aggregates, timestamp=timestamp)
self.assorted_context_database.set(singles, primes, non_primes, selected_non_primes, timestamp)
return result, singles, aggregates, new_aggregates
def dataflow_aggregations_mode(self, neighbors, timestamp, iteration):
"""
"""
# 1. collect all the contexts
input_contexts = self.get_received_data()
db_singles = self.get_database_singles(timestamp)
db_aggregates = self.get_database_aggregates(timestamp)
input_singles, input_aggregates = separate_single_and_group_contexts(input_contexts)
history = self.context_history.get(timestamp)
inputs_in_standard_form = self.input.get_in_standard_from()
unique_singles = ContextAggregator.remove_same_id_singles(input_singles.union(db_singles))
unique_aggregates = ContextAggregator.remove_same_id_aggregates(input_aggregates.union(db_aggregates))
union_contexts = unique_aggregates | unique_singles
disaggregator = Disaggregator(union_contexts)
# 3. Run disaggregator
try_count = 0
disaggregated_aggregates_set = set()
# It tries 10 times with different disaggregation setup, and give up
# giving up means that it does not find the output
while True:
try_count += 1
if try_count > 5:
#print "Did my best node(%d) - %d" % (self.id, try_count)
break
else:
pass
#if try_count > 1:
# print "(host %d) try count %d" % (self.id, try_count)
# It's in the while loop, and it means that it tries to find different aggregation.
# It again tries to find 10 times to find a new set of aggregation data
attempt_count = 10
found_new = False
for i in range(attempt_count):
disaggregated_singles, disaggregated_aggregates = disaggregator.run()
if not disaggregated_aggregates:
found_new = True # Not technically correct, but it will not cause an error due to just breaking out
break
aggregates_token = str(aggregated_contexts_to_list_of_standard(disaggregated_aggregates))
if aggregates_token not in disaggregated_aggregates_set:
found_new = True
#if i > 0:
# print "Host (%d): trying %d(th) with token %s" % (self.id, i, aggregates_token, )
disaggregated_aggregates_set.add(aggregates_token)
break
if not found_new:
#print "Host (%d): Not found the new aggregates history (%d)" % (self.id, len(disaggregated_aggregates_set))
break
# remove generated redundancies
disaggregated_singles = ContextAggregator.remove_same_id_singles(disaggregated_singles)
disaggregated_aggregates = ContextAggregator.remove_same_id_aggregates(disaggregated_aggregates)
filtered_singles = ContextAggregator.filter_singles_by_hopcount(disaggregated_singles, self.configuration)
if not disaggregated_aggregates: # no aggregates and treat the same as singles only case
# 3. The code is the same as singles except the singles are filtered out
primes = set()
non_primes = set()
selected_non_primes = set()
param = {
"singles":disaggregated_singles,
"filtered_singles":filtered_singles,
"primes":primes,
"selected_non_primes":selected_non_primes,
"timestamp":timestamp,
"iteration":iteration
}
new_info, new_aggregates = self.get_new_info(**param)
selector_result = OutputSelector(inputs=inputs_in_standard_form, context_history=history, new_info=new_info, neighbors=neighbors).run()
return self.set_database_and_return(selector_result, new_aggregates, disaggregated_singles, disaggregated_aggregates, primes, non_primes, selected_non_primes, timestamp)
primes, non_primes = get_prime(disaggregated_aggregates)
if not non_primes: # only primes
assert primes is not None, "No primes and non-primes, it's an error condition"
non_primes = set()
selected_non_primes = set()
param = {
"singles":disaggregated_singles,
"filtered_singles":filtered_singles,
"primes":primes,
"selected_non_primes":selected_non_primes,
"timestamp":timestamp,
"iteration":iteration
}
new_info, new_aggregates = self.get_new_info(**param)
selector_result = OutputSelector(inputs=inputs_in_standard_form, context_history=history, new_info=new_info, neighbors=neighbors).run()
res_val = self.set_database_and_return(selector_result, new_aggregates, disaggregated_singles, disaggregated_aggregates, primes, non_primes, selected_non_primes, timestamp)
if not is_empty_dictionary(selector_result):
return res_val
# try again if there is no output
continue
# for non-prime cases
previous_selection = self.assorted_context_database.get_selected_non_primes(timestamp)
selected_non_primes_list = GreedyMaxCover().run(non_primes, previous_selection)
# the greedy max cover can return multiple candidates for the case when
# there is nothing to send to the neighboring nodes
for i, selected_non_primes in enumerate(selected_non_primes_list):
param = {
"singles":disaggregated_singles,
"filtered_singles":filtered_singles,
"primes":primes,
"selected_non_primes":selected_non_primes,
"timestamp":timestamp,
"iteration":iteration
}
if not selected_non_primes:
#print "SHOOT %s" % aggregated_contexts_to_list_of_standard(selected_non_primes)
break
if i > 0:
print "(host %d) %d try with %s" % (self.id, i, aggregated_contexts_to_list_of_standard(selected_non_primes))
new_info, new_aggregates = self.get_new_info(**param)
selector_result = OutputSelector(inputs=inputs_in_standard_form, context_history=history, new_info=new_info, neighbors=neighbors).run()
res_val = self.set_database_and_return(selector_result, new_aggregates, disaggregated_singles, disaggregated_aggregates, primes, non_primes, selected_non_primes, timestamp)
if not is_empty_dictionary(selector_result):
return res_val
# try to send the NP that has the largest unsent data
result = ContextAggregator.get_output_from_nps(self.context_database.get_aggregates(timestamp), self.context_history.get(timestamp), neighbors)
if result:
return result, disaggregated_singles, disaggregated_aggregates, new_aggregates
# with all my efforts, no output found just return none
return self.set_database_and_return(dict(), new_aggregates, disaggregated_singles, disaggregated_aggregates, primes, non_primes, selected_non_primes, timestamp)
def dataflow_singles_mode(self, neighbors, timestamp, iteration):
"""
Assumption: 1. there exist input_contexts
"""
# 1. collect all the contexts
input_contexts = self.get_received_data()
db_singles = self.get_database_singles(timestamp)
inputs_in_standard_form = self.input.get_in_standard_from()
history = self.context_history.get(timestamp)
# 2. union, remove the redundancies
combined_singles = ContextAggregator.remove_same_id_singles(input_contexts.union(db_singles))
# 3. Run the selector with proper inputs
new_info = contexts_to_standard(combined_singles)
selector_result = OutputSelector(inputs=inputs_in_standard_form, context_history=history, new_info=new_info, neighbors=neighbors).run()
return self.set_database_and_return(
result = selector_result,
new_aggregates = None,
singles = combined_singles,
aggregates = set(), primes = set(), non_primes = set(), selected_non_primes = set(), timestamp = timestamp)
def is_this_new_timestamp(self, timestamp=0):
"""Checks if this is the start of timestamp, initially context database has {} in it,
when it has any kind of data, it implies it's not new timestamp anymore
>>> c = ContextAggregator()
>>> c.is_this_new_timestamp()
True
>>> c.set_database(set(), set())
>>> c.is_this_new_timestamp()
False
"""
if timestamp not in self.context_database.timestamp: return True
else:
return self.context_database.timestamp[timestamp] == {}
def get_received_data(self, from_node = None):
"""Returns the received data from node_index
>>> d = ContextAggregator()
>>> d.receive(1, {Context(value=1.0, cohorts=[0,1,2]), Context(value=4.0, cohorts=[3], hopcount = 1)})
>>> d.receive(2, {Context(value=2.0, cohorts=[0], hopcount=1), Context(value=4.0, cohorts=[4], hopcount = 10)})
>>> r = d.get_received_data()
>>> r = contexts_to_standard(r)
>>> same(r, [[0,3,4], [0,1,2]])
True
"""
if from_node is not None:
return self.input[from_node]
result = set()
for i in self.input.get_senders():
result |= self.input[i]
return result
def available_input_contexts(self):
"""Returns the received data from node_index
>>> d = ContextAggregator()
>>> d.receive(1, {Context(value=1.0, cohorts=[0,1,2]), Context(value=4.0, cohorts=[3], hopcount = 1)})
>>> d.receive(2, {Context(value=2.0, cohorts=[0], hopcount=1), Context(value=4.0, cohorts=[4], hopcount = 10)})
>>> d.available_input_contexts()
True
>>> d = ContextAggregator()
>>> d.available_input_contexts()
False
"""
return len(self.get_received_data()) > 0
###################################
# API
###################################
def is_nothing_to_send(self):
return is_empty_dictionary(self.output.dictionary)
def send(self, neighbor = None, timestamp=0):
"""
1. update the history
2. returns contexts in Context object
>>> c0 = ContextAggregator(0)
>>> r = c0.process_to_set_output(neighbors=[1], timestamp = 0)
>>> same(r, {1: [[0], []]})
True
>>> c1 = ContextAggregator(1)
>>> r = c1.process_to_set_output(neighbors=[0], timestamp = 0)
>>> same(r, {0: [[1], []]})
True
>>> r0 = c0.send(timestamp=0)
>>> same(contexts_to_standard(r0[1]), [[0], []])
True
>>> r1 = c1.send(neighbor=0, timestamp=0)
>>> same(contexts_to_standard(r1[0]), [[1], []])
True
"""
result = {}
output_dictionary = self.output.dictionary
# if neighbor is None:
# for o in output_dictionary:
# single_contexts = self.output.generate_single_contexts(o=o, single_contexts=self.get_database_singles(timestamp))
# aggregate_context = self.output.generate_aggregate_contexts(o=o, aggregate_contexts={self.new_aggregate} | self.get_database_aggregates(timestamp))
# result[o] = single_contexts | aggregate_context
# self.context_history.add_to_history(node_number=o, value=output_dictionary[o], timestamp=timestamp)
# else:
assert type(neighbor) in [int, long]
assert neighbor in output_dictionary
#assert self.new_aggregate is not None, "aggregate is None"
# TODO
# Duplication of code
o = neighbor
single_contexts = self.output.generate_single_contexts(o=o, single_contexts=self.get_database_singles(timestamp))
#print self.get_database_aggregates(timestamp)
if not self.new_aggregate:
new_aggregate = set()
else:
new_aggregate = {self.new_aggregate}
aggregate_context = self.output.generate_aggregate_contexts(o=o, aggregate_contexts= (new_aggregate | self.get_database_aggregates(timestamp)))
result[o] = single_contexts | aggregate_context
self.context_history.add_to_history(node_number=o, value=output_dictionary[o], timestamp=timestamp)
return result
def receive(self, from_node, contexts, timestamp=0):
"""receive_data
1. Stores the information who sent what
2. Increase the hopcount when the context is a single context
>>> d = ContextAggregator()
>>> # two contexts are received
>>> r = d.receive(1, {Context(value=1.0, cohorts=[0,1,2]), Context(value=1.0, cohorts=[0,1,3])})
>>> same(d.get_received_data(1), [[0,1,2],[0,1,3]])
True
>>>
"""
contexts = Context.increase_hop_count(contexts)
self.input[from_node] = contexts
received_info = contexts_to_standard(contexts)
self.context_history.add_to_history(node_number=from_node, value=received_info, timestamp=timestamp)
def process_to_set_output(self, neighbors=None, timestamp=0, iteration=0):
"""Process method is a generalized code for propagating contexts.
Input:
* neighbors : a dictionary that maps id -> standard contexts
* timestamp : currrent timestamp
Output:
* output dictionary: a dictionary that maps id -> standard contexts
1. When it is the first time of the propagation at timestamp, it samples the data
2. When it is not the first, it invokes the run() method
>>> a = ContextAggregator(1) # id == 1
>>> same(a.process_to_set_output(neighbors=[10,20,30]), {10: [[1], []], 20: [[1], []], 30: [[1], []]})
True
>>> same(contexts_to_standard(a.get_database_singles()), [[1],[]])
True
>>> same(a.get_database_aggregates(), [])
True
>>> a.get_input_dictionary() == {}
True
"""
if self.is_this_new_timestamp(timestamp):
sampled_data, special_flag = ContextAggregator.sample(self.get_sample_data(), timestamp)
# store the sampled data for comparison purposes
self.data = sampled_data
hopcount = 0
if special_flag:
hopcount = Context.SPECIAL_CONTEXT
context = Context(value=sampled_data, cohorts=[self.id], hopcount=hopcount, timestamp=timestamp)
self.set_database(singles={context}, aggregates=set(), timestamp=timestamp)
# store the context in the history and process
result = {}
for h in neighbors:
result[h] = [[self.id],[]]
else:
# process the early return
result = {}
if self.available_input_contexts(): # input_contexts: # if there is no inputs
if self.is_aggregation_mode():
result, combined_singles, combined_aggregates, new_aggregates = self.dataflow_aggregations_mode(neighbors, timestamp, iteration)
else:
result, combined_singles, combined_aggregates, new_aggregates = self.dataflow_singles_mode(neighbors, timestamp, iteration)
# this also reset the actual_sent_dictionary
self.output.set_dictionary(result)
# WARNING! Don't forget the input is cleared after the process_to_set_output() call
self.initalize_before_iteration()
return result
