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Introduction toHyperledger Composer

Simon Stone, Maintainer, IBM@mrsimonstone

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Blockchain for business

• Blockchain builds on basic business concepts

– Business Networks connect businesses

– Assets flow over business networks

– Transactions describe asset exchange

– Participants submit transactions

– Contracts define the rules for transactions

– The ledger is a log of transactions

• Blockchain provides a shared, replicated ledger

– Consensus, immutability, finality, provenance

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Hyperledger Fabric

• Hyperledger Fabric is a Blockchain technology that provides a technical

foundation for transactional applications across business networks:

– Smart contracts (chaincode) are executed on a distributed network

– Transaction input goes into an immutable ledger

– Transaction output goes to a data store (world state) or is published via events

• Hyperledger Fabric v1.1 was released by the community in March 2018

– Includes Node.js chaincode support, connection profile format, amongst other features.

– v1.2-rc1 released this week!

• Includes APIs for building smart contracts and client applications:

– Low level of abstraction; means that applications must be built from the ground up

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Hyperledger Fabric

• Smart contracts can provide loosely defined function based interfaces:

– “functionName”, “arg1”, “arg2”, “arg3” … “argX”

– Untyped, meaning that application development is harder

– However, provides most flexibility to the solution developer

• Smart contracts can store data in the “world state”, a key/value map stored and

managed by the blockchain network:

Key Value

CAR_1 decf546257be19758776 …

CAR_2 06aad4d65205cedb0633 ...

CAR_3 33eee744edb6688bea68 …

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Smart contracts/chaincode today

• Too much boilerplate code, not enough focus on the important business logic.

Business logic

Data validation

Access control

RPC interface

Error handling

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Hyperledger Composer

• Hyperledger Composer is a framework to accelerate the development of

applications built on top of Blockchain platforms such as Hyperledger Fabric:

– Emphasis on quick solution creation and business-centric vocabulary

– Start from the business level; model network assets, participants, and transactions

– Build applications that use business centric APIs to invoke transactions that create,

update, and delete assets and transfer them between participants

– Assets, participants, and transactions are recorded on the Blockchain in the world state

in registries

– Easily integrate Blockchain with existing business processes and systems of record

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Extensive, familiar, and open development toolset

CLI utilities

Data modelling JavaScript

business logicWeb playground

Editor support Integration

$ composer

Client libraries

composer-client

composer-admin

Code generation

Mike

Arium Logistics

Employee

Debbie

VDA Regulations

Administrator

Paul

Buyer/Owner

Tommen

Insurer

Vada

Police

Alex

Agency for Vehicle

Standards

B L O C K C H A I N

Tommen

Insurer

Vada

Police

Alex

Agency for Vehicle

Standards

Mike

Arium Logistics

Employee

Debbie

VDA Regulations

Administrator

Paul

Buyer/Owner

B L O C K C H A I N

Tommen

Insurer

Vada

Police

Alex

Agency for Vehicle

Standards

Mike

Arium Logistics

Employee

Debbie

VDA Regulations

Administrator

Paul

Buyer/Owner

Mobile

App

B L O C K C H A I N

Tommen

Insurer

Vada

Police

Alex

Agency for Vehicle

Standards

Mike

Arium Logistics

Employee

Debbie

VDA Regulations

Administrator

Paul

Buyer/Owner

Mobile

App

Enterprise

Integration

Tools

ERP

IoT

B L O C K C H A I N

Tommen

Insurer

Vada

Police

Alex

Agency for Vehicle

Standards

Mike

Arium Logistics

Employee

Debbie

VDA Regulations

Administrator

Paul

Buyer/Owner

Business

Rules

Analytics

Mobile

App

Enterprise

Integration

Tools

ERP

IoT

B L O C K C H A I N

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Links

• Hyperledger: https://www.hyperledger.org/

• Hyperledger Fabric: https://hyperledger-fabric.readthedocs.io/

• Hyperledger Composer: https://hyperledger.github.io/composer/

• Cloud playground: https://composer-playground.mybluemix.net/

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Community

• You can come and speak to us as well!

• Chat to us using Rocket.Chat at https://chat.hyperledger.org

– #fabric and #composer channels

• Ask questions on Stack Overflow

– hyperledger-fabric and hyperledger-composer tags

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Thank you!