Dragonchain blockchain platform - simplified integration of advanced blockchain features
Python PLpgSQL Thrift Shell
Latest commit 5c17c72 Jan 7, 2017 @j0j0r0 j0j0r0 committed on GitHub added crypto module docs (#83)

README.md

Dragonchain

The Dragonchain platform attempts to simplify integration of real business applications onto a blockchain. Providing features such as easy integration, protection of business data, fixed 5 second blocks, currency agnosticism, and interop features, Dragonchain shines a new and interesting light on blockchain technology.

No blockchain expertise required!

Project Goals

  1. Ease of integration of existing systems
  2. Ease of development for traditional engineers and coders unfamiliar with blockchain, distributed systems, and cryptography
  3. Client server style and simple RESTful integration points for business integration
  4. Simple architecture (flexible and usable for unforeseen applications)
  5. Provide protection of business data by default
  6. Allow business focused control of processes
  7. Fixed length period blocks
  8. Short/fast blocks
  9. Currency agnostic blockchain (multi­currency support)
  10. No base currency
  11. Interoperability with other blockchains public and private
  12. Adoption of standards as they become available (see ​W3C Blockchain Community Group blockchain standardization​)

Quick Links

Support

Maintainer

Joe Roets (j03) joe@dragonchain.org

Setup and Installation

Database Setup

Requires Postgres 9.4+

cd <Dragonchain Home>/sql
createuser blocky
createdb -O blocky blockchain
psql -U blocky -d blockchain -a -f depl.sql

Python Dependencies

Dragonchain utilized Python 2.7

To install Python library dependencies, run the following:

pip install -r requirements.txt

Code Generation

Message classes and RMI services are generated by thrift templates. If you have Apache Thrift installed you can regenerate these classes by using the gen_thrift setup command:

python setup.py gen_thrift

Keys

mkdir pki
  • Signing Key Generation openssl ecparam -name secp224r1 -genkey -out <Dragonchain Home>/pki/sk.pem
  • Verifying Key Generation openssl ec -in pki/sk.pem -pubout -out <Dragonchain Home>/pki/pk.pem
  • The signing key must be kept private. The pki directory is listed in .gitignore to prevent accidentally pushing keys to a public repository.

Logs

Pre-create a directory for log files before execution.

mkdir logs

Execution

Set the PYTHONPATH variable

export PYTHONPATH=/path/to/dragonchain

Transaction Service

python <Dragonchain Home>/blockchain/transaction_svc.py --private-key <Dragonchain Home>/pki/sk.pem --public-key <Dragonchain Home>/pki/pk.pem

Query Service

python <Dragonchain Home>/blockchain/query_svc.py [-p port] //defaults to 8080

Example Query

localhost:8080/transaction/?create_ts=1475155787 //timestamp in Unix Epoch timecode
    - create_ts can be replaced with any of the header fields in a transaction

Blockchain Processor

python <Dragonchain Home>/blockchain/processing.py --private-key <Dragonchain Home>/pki/sk.pem --public-key <Dragonchain Home>/pki/pk.pem

--private-key (required - signing key for transaction service and processing module)
--public-key  (required)
--host        (defaults to localhost)
--port, -p    (defaults to 8080)
--phase       (required)

Configuration

Configuration within yaml files within configs directory.

Environment Variables

BLOCKCHAIN_DB_HOSTNAME = Hostname of the database instance (default localhost)

BLOCKCHAIN_DB_PORT = Port of the database server (default 5432)

BLOCKCHAIN_DB_USERNAME = Database username (default blocky)

BLOCKCHAIN_DB_PASSWORD = Database password (default None)

BLOCKCHAIN_DB_NAME = Blockchain database (default blockchain, also selects .yaml config and log file with same name)

Contribution

Dragonchain uses a standard Feature Branch Workflow.

All feature development should take place in Git branch dedicated to that feature. A feature branch should be named starting with the ticket ID followed by a dash and a short description.

Issues are tracked within Github: Dragonchain Issues

Formatting

Code should follow the PEP 8 Style Guide for Python code where possible.

Contributors

Disclaimer

The comments, views, and opinions expressed in this forum are those of the authors and do not necessarily reflect the official policy or position of the Walt Disney Company, Disney Connected and Advanced Technologies, or any affiliated companies.

All code contained herein is provided “AS IS” without warranties of any kind. Any implied warranties of non-infringement, merchantability, and fitness for a particular purpose are expressly disclaimed by the author(s).

License

Copyright 2016 Disney Connected and Advanced Technologies

Licensed under the Apache License, Version 2.0 (the "Apache License")
with the following modification; you may not use this file except in
compliance with the Apache License and the following modification to it:
Section 6. Trademarks. is deleted and replaced with:

     6. Trademarks. This License does not grant permission to use the trade
        names, trademarks, service marks, or product names of the Licensor
        and its affiliates, except as required to comply with Section 4(c) of
        the License and to reproduce the content of the NOTICE file.

You may obtain a copy of the Apache License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the Apache License with the above modification is
distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied. See the Apache License for the specific
language governing permissions and limitations under the Apache License.