@hyperbitjs/rpc

@hyperbitjs/rpc

Hyperbit - RPC

A simple, typed JSON-RPC client for any JSON-RPC service.

Install

# Using npm
npm install @hyperbitjs/rpc

# Using yarn
yarn add @hyperbitjs/rpc

Optional setup:

• Copy rpc/.env.example to .env and fill values before running examples.

30-Second Quick Start

import { createClient } from '@hyperbitjs/rpc';

const rpc = createClient({
  url: process.env.RPC_URL,
  username: process.env.RPC_USER,
  password: process.env.RPC_PASSWORD,
});

const info = await rpc.requestOrThrow('getblockchaininfo');
console.log(info);

One-line env setup

import { createClientFromEnv } from '@hyperbitjs/rpc';

const rpc = createClientFromEnv();
const info = await rpc.requestOrThrow('getblockchaininfo');
console.log(info);

Run the example script after building:

npm run build
node examples/from-env.mjs

Quick Start (Any JSON-RPC Node)

import { Client, createClient } from '@hyperbitjs/rpc';

const client = createClient({
  url: 'http://127.0.0.1:9050',
  username: 'username',
  password: 'password',
});

const response = await client.request('getchaintips');

if (Client.isRpcError(response)) {
  console.error('RPC error', response);
} else {
  console.log('RPC result', response);
}

Same call with params

const tx = await client.request('getrawtransaction', ['<txid>', true]);

if (!Client.isRpcError(tx)) {
  console.log(tx);
}

Throw-on-error usage

import { Client } from '@hyperbitjs/rpc';

const client = new Client({
  url: 'http://127.0.0.1:9050',
  auth: { username: 'username', password: 'password' },
});

const blockCount = await client.requestOrThrow('getblockcount');
console.log(blockCount);

Batch requests

const results = await client.batchRequest([
  { method: 'getblockcount' },
  { method: 'getdifficulty' },
]);

console.log(results);

API Reference

• new Client(config) - create RPC client instance.
• createClient(config) - ergonomic factory function.
• createClientFromConfig(config) - create client from optional/partial config with required URL enforcement.
• createClientFromEnv(env?) - create client from RPC_* env vars.
• client.request(method, params?, requestConfig?) - returns result or RpcError.
• client.requestOrThrow(method, params?, requestConfig?) - throws on error.
• Client.isRpcError(value) - type-safe error guard.

Config

• url (required): RPC endpoint.
• username / password (optional): basic auth credentials.
• auth (optional): { username, password } alternative to username/password fields.
• headers (optional): custom request headers.
• httpOptions (optional): default Axios request options.

Error handling

request() returns either a result or a typed RpcError.

Common error types:

• ValidationError: invalid local call data (for example empty method name).
• RpcError: server responded with an RPC/HTTP error.
• ServerUnreachable: node could not be reached (bad URL, node down, etc.).

Best practice implementation pattern

const result = await client.request('getblockcount');

if (Client.isRpcError(result)) {
  // centralize logging/telemetry here
  console.error(result.type, result.message, result.description);
  return;
}

console.log(result);

Troubleshooting

1) ServerUnreachable

What it means:

• Your app cannot reach the node at the configured URL.

Quick checks:

• Confirm the node process is running.
• Confirm URL/port are correct for your RPC service.
• Make sure firewall/container networking allows access.

2) Auth errors (401 / 403)

What it means:

• Credentials are invalid or missing.

Quick checks:

• Verify rpcuser and rpcpassword in your node config.
• Verify your app is using the same username/password.
• Prefer one auth style only:
  • auth: { username, password }
  • or username + password

3) ValidationError

What it means:

• Local request is invalid before sending.

Quick checks:

• Ensure method name is a non-empty string.
• Ensure params are array/object values expected by the RPC method.

4) Method-level RPC errors

What it means:

• Node was reached, but RPC call failed (bad params, unknown method, wallet state, etc.).

Quick checks:

• Try the same method directly in your node RPC console.
• Double-check method name and parameter order.
• Log error.code, error.message, and error.description from RpcError.

Production checklist

• Timeouts: set timeout explicitly (for example 15000–30000) based on your SLA.
• Retries: use small retry counts (retries: 1 or 2) and short retryDelay for transient failures.
• Logging: use logLevel: 'warn' or logLevel: 'error' in production to reduce noise.
• Secrets: load RPC credentials from environment variables, never hard-code in source.
• Health checks: run a lightweight call like getblockcount on startup/readiness checks.
• Error handling: centralize handling for ServerUnreachable, RpcError, and ValidationError.
• Batch safety: validate batch inputs and handle partial failures before assuming all responses succeeded.

Example production config:

import { createClient } from '@hyperbitjs/rpc';

export const rpc = createClient({
  url: process.env.RPC_URL,
  username: process.env.RPC_USER,
  password: process.env.RPC_PASSWORD,
  timeout: 20000,
  retries: 1,
  retryDelay: 750,
  logLevel: 'warn',
});

Overview

This project lives at rpc and is part of the broader multi-project workspace. Description: No description provided yet.

Purpose

• Deliver the core capability owned by this project.
• Provide stable commands and interfaces for other apps/packages in the workspace.
• Keep implementation details localized so changes stay maintainable.

Architecture Notes

• Type: Project
• Package manager metadata source: package.json
• Runtime entry hints: dist/index.cjs

Setup

1. Install dependencies from this directory:

npm install

1. Run key scripts as needed (see script table below).
2. Environment template exists at .env.example.

NPM Scripts

Script	Command
clean	node -e "require('fs').rmSync('dist',{recursive:true,force:true})"
build	vite build
prebuild	npm run clean
test	vitest --run
test:watch	vitest
lint	eslint .
lint:fix	eslint . --fix && prettier --write .
format	prettier --write .
type-check	tsc --noEmit

Dependencies

Production

• axios: ^1.7.0

Development

• @typescript-eslint/eslint-plugin: ^7.18.0
• @typescript-eslint/parser: ^7.18.0
• eslint: ^8.57.0
• prettier: ^3.3.3
• typescript: ~5.5.4
• vite: ^6.4.1
• vitest: ^4.0.18

Configuration

• Primary config source: package.json
• Environment template: .env.example
• Add project-specific operational notes to MEMORY_BANK.md.

Development Workflow

1. Make changes in focused modules.
2. Run the smallest relevant script/test first.
3. Run full validation scripts before merging.
4. Update this README and memory bank whenever behavior/contracts change.

Testing and Validation

• Prefer script-driven checks from the table above (for example: test, build, lint).
• If this project has no tests yet, add smoke checks and document them in MEMORY_BANK.md.

LLM Context

When using an LLM coding assistant in this folder, always include:

• Exact target file paths and expected behavior changes.
• Validation command(s) run after edits.
• Runtime/config assumptions (.env, API keys, ports, external services).

Memory Bank

See MEMORY_BANK.md for operational context, commands, and troubleshooting notes.