It is a Blockchain-based application designed to manage property transactions using digital currency. This system facilitates secure and transparent property trading through blockchain technology, ensuring data integrity with cryptographic methods like HMAC , hash functions and Merkle trees and consensus algorithms like proof of work.

Steps to run

• default.py contains some default properties and users for the purpose of testing, more users and properties may be registered by choosing appropriate options in menu

• Menu has options for various operations that may be carried out as part of the functioning of a real estate management system.

Details About Contents of files

1. block.py: Blockchain Management

• Class BlockChain: Manages the entire blockchain, maintaining a list of blocks and transactions.

• new_block(self, previous_hash=None, transaction=None): Creates a new block with transactions, assigns a Merkle root, and computes the block's hash. previous_hash: The hash of the previous block in the chain. transaction: Optional transaction details to include in the block.

• hash(block): Computes and returns a SHA-256 hash of the block. block: The block data to hash.

• last_block(self): Returns the most recent block in the blockchain.

• get_block(self, index): Retrieves a block by its index in the chain.

• get_chain(self): Returns the entire blockchain as a list of blocks.

• get_transaction_by_user(self, username): Returns all transactions in which user with username was involved

• mine_block_POW(self , block): Proof of work Consensus to verify the transaction block before adding it to the chain

• is_chain_valid(self): Check if chain has been tampered by computing and comparing hashes of blocks with prev hash of next block

2. hmac_.py: Security

Contains utilities to implement HMAC for securing transactions. It provides functions to generate and verify HMACs ensuring the authenticity and integrity of messages.

3. main.py: Main Application Entry

Serves as the entry point for running the application. Initializes the blockchain and handles user interactions such as registering users, adding properties, and processing transactions.

4. merkle_tree.py: Merkle Tree Implementation

• Class MerkleTree: Implements a Merkle tree to summarize and verify transaction data efficiently.

• getRootHash(): Calculates and returns the root hash of the Merkle tree, representing a summary of all transactions.

5. models.py: Data Models

• Class User: Represents a user in the system with attributes like username, password, assets, and digital wealth.

  • add_property(self, property): Registers a new property to the user's list of assets.

  • remove_property(self, property): Removes a property from the user's assets and adjusts their digital wealth accordingly.

  • register_property(self, property): List a property as a user and set name , price

  • addMoney(self, amount): Add money to wallet , check balance

• Class Transaction: Handles the logic for buying and selling properties between users.

  • to_string(self): Returns a string representation of the transaction details.

• Class Property: Represents a property with attributes like name, owner, and value.

  • viewProperties(self): View All Listed properties with details

  -getProperty get details of a specific property

GROUP DETAILS -

Aryan Saluja 2021A7PS2947H Kushagra Patni 2021A3PS2985H Shreya Kumar 2021A7PS1508H Varayuru Pranava Sukrutha 2020A8PS0695H Divyank Shrivastav 2020A1PS2187H