Search_Engine/test_merge.py

117 lines
3.5 KiB
Python

import json
from posting import Posting
import math
import sys
import random
from nltk.corpus import words
random_list = [1,2,3,4,5,6,7,8,9,10]
test_data = words.words()
random.shuffle(test_data)
def random_posting(id):
return Posting(id,random.choice(random_list),random.choice(random_list),[random.choice(random_list),random.choice(random_list),random.choice(random_list),random.choice(random_list),
random.choice(random_list),random.choice(random_list),random.choice(random_list),random.choice(random_list)])
class Node():
index_value = 'Something'
postings = list()
class Index():
length = 0
index = list()
def random_partial_index(name):
part_index = Index()
part_index.index = list()
part_index.length = 0
with open(name +'.partial', 'w') as f:
for i in range(1000):
node1 = Node()
node1.index_value = random.choice(test_data).lower()
node1.postings = list()
for i in range(10):
node1.postings.append(random_posting(i))
jsonStr = json.dumps(node1, default=lambda o: o.__dict__,sort_keys=False)
part_index.index.append((node1.index_value,f.tell()))
f.write(jsonStr + '\n')
part_index.length = part_index.length + 1
part_index.index.sort(key=lambda y:y[0])
jsonStr =json.dumps(part_index, default=lambda o: o.__dict__,sort_keys=False)
with open(name + '.index','w') as f:
f.write(jsonStr)
def merge(partial_indices):
partial_files = list()
partial_index_files = list()
parital_index_indices = list()
merged_index = open("merged_index.full",'w')
num_indices = len(partial_indices)
#Full Index.Index and Length
full_index = Index()
full_index.index = list()
full_index.length = 0
for partial_index in partial_indices:
file = open(partial_index+'.partial','r')
partial_files.append(file)
index = open(partial_index+'.index','r')
partial_index_files.append(index)
for partial_index_file in partial_index_files:
partial_index_file.seek(0,0)
parital_index_indices.append(json.loads(partial_index_file.readline()))
#Start all indexes at 0
for partial_file in partial_files:
partial_file.seek(0,0)
pointers = [0]*num_indices
while(True):
#Get all values from all indices to find min
value = None
values = list()
for i in range(num_indices):
if pointers[i] < parital_index_indices[i]['length']:
values.append(parital_index_indices[i]['index'][pointers[i]][0])
if(len(values) == 0):
break
value = min(values)
#Get data from the min value of all indices if exists then save to mergedIndex
if value == None:
print("I have crashed some how by not getting min value")
break
node = Node()
node.index_value = value
for i in range(num_indices):
if pointers[i] < parital_index_indices[i]['length'] and parital_index_indices[i]['index'][pointers[i]][0] == value:
to_seek = parital_index_indices[i]['index'][pointers[i]][1]
partial_files[i].seek(to_seek,0)
json_value = partial_files[i].readline()
temp_node = json.loads(json_value)
node.postings = node.postings + temp_node['postings']
pointers[i] = pointers[i] + 1
node.postings.sort(key=lambda y:y['doc_id'])
full_index.index.append((value,merged_index.tell()))
full_index.length = full_index.length + 1
jsonStr = json.dumps(node,default=lambda o: o.__dict__,sort_keys=False)
merged_index.write(jsonStr + '\n')
full_index.index.sort(key=lambda y:y[0])
jsonStr =json.dumps(full_index, default=lambda o: o.__dict__,sort_keys=False)
with open("merged_index.index" ,'w') as f:
f.write(jsonStr)