API Reference

KalyChain provides comprehensive APIs for interacting with the blockchain. This section covers available access methods and API endpoints.

Access Methods

KalyChain supports multiple API protocols:

Protocol	Transport	Use Case
JSON-RPC	HTTP, WebSocket, IPC	General blockchain interaction
RPC Pub/Sub	WebSocket	Real-time event subscriptions
GraphQL	HTTP	Complex queries, reduced overhead

Enabling API Access

Enable APIs using command-line options when starting your node:

kaly --rpc-http-enabled \
     --rpc-ws-enabled \
     --graphql-http-enabled \
     --rpc-http-host=0.0.0.0 \
     --rpc-http-port=8545

Available Options

Option	Description	Default
--rpc-http-enabled	Enable JSON-RPC over HTTP	false
--rpc-ws-enabled	Enable JSON-RPC over WebSocket	false
--graphql-http-enabled	Enable GraphQL over HTTP	false
--rpc-http-host	HTTP API host	127.0.0.1
--rpc-ws-host	WebSocket API host	127.0.0.1
--graphql-http-host	GraphQL API host	127.0.0.1
--rpc-http-port	HTTP API port	8545
--rpc-ws-port	WebSocket API port	8546
--graphql-http-port	GraphQL API port	8547

Default Ports

Service	Port
JSON-RPC HTTP	8545
JSON-RPC WebSocket	8546
GraphQL HTTP	8547

Security

Host Allowlist

By default, KalyChain only accepts connections from localhost and 127.0.0.1. To allow other hosts:

kaly --host-allowlist=example.com,api.example.com

For development only (not recommended for production):

kaly --host-allowlist="*"

CORS Configuration

Configure Cross-Origin Resource Sharing for browser access:

kaly --rpc-http-cors-origins="https://app.example.com"

Authentication

For production APIs, enable authentication:

kaly --rpc-http-authentication-enabled \
     --rpc-http-authentication-credentials-file=auth.toml

See Hyperledger Besu Authentication for detailed configuration.

Remote Access

When exposing APIs remotely, always:

• Use a firewall to restrict access
• Enable authentication
• Use HTTPS via a reverse proxy
• Set specific host allowlists

API Method Categories

Ethereum Standard Methods

Namespace	Description
eth_	Core Ethereum operations
net_	Network information
web3_	Client utilities

KalyChain Methods

Namespace	Description
qbft_	QBFT consensus operations
txpool_	Transaction pool queries
admin_	Node administration
debug_	Debugging utilities

Quick Examples

Get Block Number

curl -X POST --data '{
  "jsonrpc":"2.0",
  "method":"eth_blockNumber",
  "params":[],
  "id":1
}' -H "Content-Type: application/json" http://localhost:8545

Get Balance

curl -X POST --data '{
  "jsonrpc":"2.0",
  "method":"eth_getBalance",
  "params":["0xYourAddress", "latest"],
  "id":1
}' -H "Content-Type: application/json" http://localhost:8545

Send Raw Transaction

curl -X POST --data '{
  "jsonrpc":"2.0",
  "method":"eth_sendRawTransaction",
  "params":["0xSignedTransactionHex"],
  "id":1
}' -H "Content-Type: application/json" http://localhost:8545

Not Supported

KalyChain (like Besu) does not support:

• Account Management — No private key storage. Use eth_sendRawTransaction with externally signed transactions.
• Whisper Protocol — Peer-to-peer messaging (deprecated).
• Swarm Protocol — Distributed storage.

In This Section

• JSON-RPC — HTTP and WebSocket JSON-RPC.
• GraphQL — GraphQL queries.
• RPC Pub/Sub — WebSocket subscriptions.

Further Reading

• Hyperledger Besu API Reference — Complete method documentation.
• Events and Logs — Working with contract events.