The project here is a final project submitted for the cryptocurrency course. It proposes a proof of concept for a decentralized news platform that integrates third-party fact-checkers as well as crowdsourced community evaluations. Such a platform relies on the community to evaluate and verify the authenticity of a news article. With this approach, we hope that the news storage and evaluation process would be secure yet not controlled by a single organization or entity; it also encourages the community to get more involved in societal development and informed on social issues.

The project has implemented a simple blockchain structure in Python. It covers some of the core features of a typical blockchain, including transactions, proof-of-work, mining, etc. It incorporated the Merkle tree structure into the block for the storage of user-submitted evaluations. Essentially, each block would contain articles/claims with evaluations/ratings coming from third-parties (Google Fact Checking API) and users.

The project uses pipenv to manage library dependencies. To install the dependencies, please type the following command into the terminal:

pipenv install

After successfully installing the dependencies, blockchain.py can be executed with the following command:

pipenv run python src/blockchain.py

The command would display a sample output containing the Merkle tree as well as the constructed blocks in the form of a dictionary.

We have also attempted to implement a simple API for the blockchain.py with FastAPI in main.py. Due to the time constraint, it is only a basic API that covers the functions like adding transactions and mining. To execute and have a simple API framework running on the localhost, you can type the following command into the terminal:

pipenv run uvicorn src.main:node --reload

You can also visit http://127.0.0.1:8000/#docs to see a visual representation of the framework.

To run the test cases for the project, please type the following command:

pipenv run pytest tests

[{'hash': '0026d3b0417944aced50f4a54d778e3a84fd736792fe9afb1491be8108e29468',
  'index': 1,
  'news': {'mean': 3.5,
           'review': ['False',
                      'False',
                      'Pants on Fire',
                      'False',
                      'Lacks Context',
                      'Out of Context',
                      'False',
                      'False',
                      'No Evidence',
                      'Distorts the Facts'],
           'stdev': 1.8708286933869707,
           'value': 'coronavirus is a hoax',
           'variance': 3.5},
  'nonce': 229,
  'previous_hash': '008f6bcb16941fe8e92280815931b780efd9b178bf082f4cf7177bf8e5310091',
  'timestamp': '2021-02-12 04:02:17.933808',
  'transactions': 'ecc3e0e80e48af9c78cec2a446399b2a98ecda6dbf7ef6446cfbf3730feff804'},
 {'hash': '00f7d7932f8f12af37de848c06e890f50b3fcfc437ce8f080dbabf24c52a1e31',
  'index': 2,
  'news': {'mean': 8.5,
           'review': ['The Pfizer vaccine has an efficacy rate of over 90%. '
                      'The 99.96% figure is not an efficacy rate but the '
                      'proportion of people vaccinated in Israel who did not '
                      'later test positive for the virus.',
                      'Mostly true'],
           'stdev': 3.605551275463989,
           'value': 'vaccine is good',
           'variance': 13.0},
  'nonce': 578,
  'previous_hash': '0026d3b0417944aced50f4a54d778e3a84fd736792fe9afb1491be8108e29468',
  'timestamp': '2021-02-12 04:02:18.517646',
  'transactions': 'd165578d6b1b487d31e7029de4140f4c6144f2fb13026f3d7d277eccb7248ddb'}]