Communication II
Building and Integrating Custom RPC Handlers
The core objective of this module is to guide you through building a fully functional custom RPC handler from scratch, including its registration, validation logic, ledger access routines, error-handling strategy, and complete test suite.
Module overview
Custom RPC handlers are the gateway to extending rippled’s capabilities, enabling developers to introduce new queries, operations, and integrations tailored to specific use cases. Building on the RPC architecture knowledge from the previous module, you will now apply everything you’ve learned to design, implement, and test your own RPC handlers.
In this module
You’ll apply the principles of handler architecture, request flow, authentication, and error-handling patterns to create production-ready RPC handlers.
The implementation process walks you through defining clear function signatures, performing robust input validation, executing ledger queries, and constructing results that follow established XRPL conventions.
A dedicated section on testing introduces strategies to ensure correctness and reliability, using unit tests, mock objects, and integration testing. The module also explores advanced capabilities that go beyond simple request–response logic, including streaming, subscriptions, and batch processing.
Through hands-on exercises, you’ll build a full custom handler from initial registration to end-to-end testing. You’ll also learn best practices for code organization, performance optimization, and documentation standards.
This practical experience serves as a solid foundation for anyone looking to extend rippled’s functionality, build developer tools, or contribute to the broader XRPL ecosystem.
Learning objectives
Handler Implementation
Write complete handler functions with proper signatures, input validation, and result construction.
Ledger Access
Query ledger data, account information, and transaction history through context APIs.
Testing Strategies
Build unit tests, use mock objects, and create integration tests for comprehensive coverage.
Advanced Features
Implement streaming responses, subscription mechanisms, and batch request processing.
Best Practices
Follow established patterns for maintainability, performance, and code quality.
