Hyperledger-Operated Blockchain Integration: Writing, Deploying and Testing Custom Chaincode

Blockchain is a specific Distributed Ledger Technology (DLT) that is an emerging technology currently disrupting various fields. The aim of this paper is to explore ways to harness the advantages of blockchain while being implemented to existing systems. A permissioned blockchain can be established through Hyperledger Fabric (HLF) that utilizes ledgers that are interacted upon by a chaincode. An HLF network was established to investigate the custom chaincode. The scenario of the project was grounded on the functions performed in a web-based property inventory management system that uses a centralized database. The chaincode in the project was written using JavaScript and Node.js was used to create the whole chaincode source. A channel was built between the nodes of the blockchain where the chaincode was deployed. Subsequently, to open a gateway to the network, multiple Representational State Transfer (RST) Application Programming Interface (API) were created. Several gateway endpoints were tested through Insomnia, a cross-platform API client for RST. The tests performed employed various request methods (GET, POST, PUT, and DELETE) which resulted in evidence that the custom chaincode is fully functional and adheres to the OpenAPI specification. The paper concludes that it is highly feasible and advantageous to integrate a blockchain into an existing Web 2.0 system. Most functions and business logic in existing traditional systems can be reflected in a chaincode with proper planning and execution. In the future, other aspects of the blockchain network will be explored further.