Distributed Ledger Technologies / Blockchain : Software Design Patterns

Written conform to the principles and terminology of Blockchain.

Data Patterns

Merkle Tree

Structure

Instance

Where node[1.1].signature = hash(concatenate(node[1.1.1].toString(),node[1.1.2].toString()))) etc.

Applications

• Git
• Modern File Systems

Merkle Trie / Blockchain

Structure

Instance

Where root[i+1].signature = hash(concatenate(root[i].toString(),block[i].toString())) etc.

Applications

• Blockchain

Block

Applications

• Blockchain

Transaction

Applications

• Blockchain

Behavior Patterns

Singleton

One single instance of:

• data
• behavior
• events

Applications

• Blockchain

(Smart) Contract

Mortal Contract

By default the contracts are immortal. They could trap funds if they cannot be stopped from operation.

Contract Interoperativity

Contract1, 2, 3 are interoperable

Oracle

Observer/Judge

Structure

Usage

A more detailed UML and implementation: ontrack-dapp

Composite Patterns

Twin Contracts

Twin smart contracts usually are born and die together. Also the transcations they initiate are born in synchronicity and atomically in mirror on their respective newtorks.

Contract Factory

Contract of Contracts

A contract that implements contract factory for any number of contracts.

Structure

Usage

Thanks

Diagrams drawn using Nomnoml and JS Sequence Diagrams.