Modeling a Business Network Using Hyperledger Composer

Hyperledger Composer is a set of collaboration tools for business owners and developers that make it easy to write chaincode for Hyperledger Fabric and decentralized applications (DApps). With Composer, you can quickly build POC and deploy chaincode to the blockchain in a short amount of time. Hyperledger Composer consists of the following toolsets:

• A modeling language called CTO: A domain modeling language that defines a business model, concept, and function for a business network definition
• Playground: Rapid configuration, deployment, and testing of a business network
• command-line interface (CLI) tools: The client command-line tool is used to integrate business network with Hyperledger Fabric

In this chapter, we will explore the Composer business network and development components, including implementing models, transaction logic, access control, and query definitions. We will set up a development environment, and cover the use of the Hyperledger Playground for testing. We will also write client-side code and call chaincode using the client SDK.

In this chapter, we will cover the following recipes:

• The Hyperledger Composer business network and development components
• Setting up the Hyperledger Composer prerequisites environment
• Setting up the development environment
• Configuring a Composer business network
• Implementing models, transaction logic, access control, and query definitions

• Deploying, testing, and exporting business network archives using the Composer command-line interface 
• Interacting with Composer through the RESTful API