Created
May 25, 2012 16:04
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Recover deleted data from mongo DB database
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"""A little script to recover deleted recording of a mongoDB db file | |
There's no optimization but it work and has saved me | |
""" | |
import struct | |
import bson | |
import pymongo | |
import sys | |
def decode_chunck(chunck): | |
"Try to decode a chunck" | |
#if not bson.is_valid(chunck): | |
# return None | |
try: | |
result = bson.decode_all(chunck)[0] | |
if not result: | |
return None | |
else: | |
# if there's all the searched field, return it | |
if 'field_1' in result and 'field_2' in result and 'field_3' in result: | |
return result | |
except Exception: | |
return None | |
return None | |
def generate_chunck(data, pos=0): | |
"Generator to create chunck" | |
print "open at: %s" % pos | |
f= open(data,'rb') | |
a=f.read() | |
size = len(a) | |
while pos < size: | |
# Progress indicator | |
if pos % 1024 ==0: | |
print pos | |
# Determine the size of the possible bson encoded data | |
bson_size = struct.unpack("<I", a[pos:pos + 4])[0] | |
# If it's more than 2KB reject it (perfect for me) | |
if bson_size > 2*1024: | |
# Continue tu search in the file | |
pos += 1 | |
continue | |
# If the bson is bigger than the file, reject it | |
if bson_size+pos > size-1: | |
pos += 1 | |
continue | |
# A bson should end by \x00 | |
# http://bsonspec.org/#/specification | |
if a[pos+bson_size] != '\x00': | |
pos += 1 | |
continue | |
# Chunck it | |
chunck = a[pos:pos+bson_size] | |
pos += 1 | |
yield chunck | |
# create connection | |
connection = pymongo.Connection('localhost', 27017) | |
# Connect to MongoDB in order to reinsert the data | |
db = connection.recover_db | |
collection = db.recover_collection | |
# argv[1] = the file to recover | |
# argv[2] = Where to start in the file | |
for chunck in generate_chunck(sys.argv[1], int(sys.argv[2])): | |
result = decode_chunck(chunck) | |
if result: | |
print "insert" | |
collection.insert(result) | |
Could you please show sample of argv1 and argv2?
and Where can found the file in both argv ?
Thank you in advance.
This didn't work for me on Mongo 2.4, apparently the file format has changed and now mongo overwrites the object size with \xee\xee\xee\xee. I have a gist here: https://gist.github.com/guss77/f8e610cfddbe02c07896 that modifies the above code to try to guess at the recoverable size of an object.
Showing : ./recover.py: line 8: syntax error near unexpected token (' ./recover.py: line 8:
def decode_chunck(chunck):
@egguy can u please give an example for argv[1] and argv[2], since i dont know which file do we have to feed it.
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hi man, this is to recover some data of one database, but can not recover a drop database, is it?