README.md

cchain

Blockchain implementation(to store digital cheque transfers) based on apache cassandra distributed database. We implemented all consensus based on cassandra cluster with scala language

Set up and run

1. Run cassandra

docker run -d -p 9160:9160 -p 9042:9042 erangaeb/cassandra:0.2

2. Connects to cassandra(cqlsh)

# command
cqlsh <docker host> 9042 --cqlversion="3.4.4"

# example
cqlsh localhost 9042 --cqlversion="3.4.4"

3. Create keyspace

CREATE KEYSPACE cchain WITH REPLICATION = {'class' : 'SimpleStrategy', 'replication_factor': 1}

4. Create tables

CREATE TYPE IF NOT EXISTS cchain.cheque (
  bank_id TEXT,
  id UUID,
  amount INT,
  img TEXT
);

CREATE TYPE IF NOT EXISTS cchain.transaction (
  bank_id TEXT,
  id UUID,
  cheque_bank_id UUID,
  cheque_id TEXT,
  cheque_amount INT,
  cheque_img TEXT,
  from_acc TEXT,
  to_acc TEXT,
  timestamp BIGINT,
  digsig TEXT
);

CREATE TYPE IF NOT EXISTS cchain.signature (
  bank_id TEXT,
  digsig TEXT
);

CREATE TABLE IF NOT EXISTS cchain.cheques (
  bank_id TEXT,
  id UUID,
  amount INT,
  img TEXT,

  PRIMARY KEY(bank_id, id)
);

CREATE TABLE IF NOT EXISTS cchain.transactions (
  bank_id TEXT,
  id UUID,
  cheque_bank_id UUID,
  cheque_id TEXT,
  cheque_amount INT,
  cheque_img TEXT,
  from_acc TEXT,
  to_acc TEXT,
  timestamp BIGINT,
  digsig TEXT,

  PRIMARY KEY(bank_id, id)
);

CREATE TABLE IF NOT EXISTS cchain.blocks (
  bank_id TEXT,
  id UUID,
  transactions SET<frozen <transaction>>,
  timestamp BIGINT,
  merkle_root TEXT,
  pre_hash TEXT,
  hash TEXT,
  signatures SET<frozen <signature>>,

  PRIMARY KEY(bank_id, id)
);

CREATE TABLE IF NOT EXISTS cchain.keys (
  bank_id TEXT,
  id UUID,
  transactions SET<frozen <transaction>>,
  signatures SET<frozen <signature>>,
  timestamp BIGINT,

  PRIMARY KEY(bank_id, id)
);

CREATE CUSTOM INDEX IF NOT EXISTS transactions_index ON cchain.transactions ()
USING 'com.stratio.cassandra.lucene.Index'
WITH OPTIONS = {
  'refresh_seconds': '1',
  'schema': '{
    fields: {
      bank_id: {type: "string"},
      id: {type: "uuid"},
      from_acc: {type: "string"},
      to_acc: {type: "string"},
      cheque_id: {type: "string"}
    }
  }'
};

5. Run zchain

Run via docker compose