Story Blockchain

In this project , I have implemented blockchain technology with python. Here the data can not be changed or modify.So the database file can be share with anyone. If the person changes the database , we can detect it very easily.

Installation

Install python 3.6 or higher version. And run this command

  pip install pycryptodome

Documentation

Add a writer

code

from lib.Writer import Writer

objWriter=Writer()
print(objWriter.add(name="Argha Nilanjon Nondi",nId="12992749084",description="New member",level=3,char="0"))

if the level=3 and char="0" then the hash will start with 000.The time to add a new writer will depends on the level . If the level is increased , the time will be increased as well.

output

{
   "private_key": "2d2d2d2d2d424547494e205253412050524956415445204b45592d2d2d2d2d0a4d4949435851494241414b42675143764a57786177......", 
   "public_key": "2d2d2d2d2d424547494e205055424c4943204b45592d2d2d2d2d0a4d494......"
}

Here public_key is saved on ledger.sqlite but the private_key is not saved on ledger.sqlite. A user must save it on their computer and they should not share it with anyone but public_key can be shared with anyone

Verify the Writers chain

code

from lib.Writer import Writer

objWriter=Writer()
print(objWriter.verify())

output 1

True

If anybody does not modify the data of the table named 'Writers' of 'Ledger.sqlite'

output 2

False

If anybody modifies the data of the table named 'Writers' of 'Ledger.sqlite'

Add a story

code

from lib.Story import Story

privateKey="""2d2d2d2d2d424547494e205253412050524956415445204b45592d2d2d..."""
objStory=Story()
print(objStory.add(privateKey=privateKey,storyName="Doctor Sleep",storyDescription="A horror thriller book",level=3,char="0"))

if the level=3 and char="0" then the hash will start with 000.The time to add a new writer will depends on the level . If the level is increased , the time will be increased as well. Here hash is not the signature.

output

7011f882ad281ec19f300a4c9017961338f48ecacdcbb4b370dda34eaae5e9601......

It is the signature of a story and it can be shared with anyone.

Verify the Stories chain

code

from lib.Story import Story

objWriter=Story()
print(objWriter.verify())

output 1

True

If anybody does not modify the data of the table named 'Stories' of 'Ledger.sqlite'

output 2

False

If anybody modifies the data of the table named 'Stories' of 'Ledger.sqlite

Verify a signature

code

from lib.Story import Story

signature="5f9dc207c0577846a40cf5c4fecb4b781d7980482e4b6fa62cfb63514be01d581535d59da29a....."

publicKey="""2d2d2d2d2d424547494e205055424c4943204b45592d2d2d2d2d0a4d4947664d413047......."""

objStory=Story()
print(objStory.check_signature(signature=signature,publicKey=publicKey))

output 1

True

If anybody does not modify the data of the table named 'Stories' of 'Ledger.sqlite' or the signature is connected to public key

output 2

False

If anybody modifies the data of the table named 'Stories' of 'Ledger.sqlite or the signature is not connected to public key

Built with

python
sql
sqlite
- blockchain
- cryptography

Note

If you open the 'Ledger.sqlite' , you can not find the private key . So the database is a public ledger and it can shared with anyone.
The level argument indeicates the hash complexity . The level argument is an integer type and it has the range of 1 to 64.
You can change the 'getHash(data=,num=)' function in 'SecretCrypto/init.py' so that the hacker can not guess how hashes are being generated.
I said earlier that you can share the 'Ledger.sqlite' with anyone but I will suggest that do not share the python scripts.
You can use the pattern in other scenarios. Like storing hash of files .