JSON-RPC

This document introduces the common problems and operation methods of JuChain node construction and JSON-RPC API calls, which is suitable for developers to quickly integrate and troubleshoot.

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Quick Start

1. Supported operating systems

JuChain nodes support mainstream Linux distributions (such as Ubuntu, CentOS), macOS, and Windows (WSL is recommended).

2. Get the node program

• Endpoint : https://testnet-rpc.juchain.org

• Example (query block height):

  curl -X POST -H "Content-Type: application/json" --data '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}' https://testnet-rpc.juchain.org

• response :

  {"jsonrpc":"2.0","id":1,"result":"0x1a2b3c"}

3. Quickly start a full node

Take Linux as an example:

wget https://github.com/juchain/juchain/releases/download/vX.Y.Z/juchain-linux-amd64.tar.gz
tar -xzvf juchain-linux-amd64.tar.gz
cd juchain
./juchain --network mainnet

• --network mainnet indicates the main network, and the test network can be used --network testnet .

4. Node synchronization time

The time for the first full synchronization depends on the network bandwidth and hard disk performance, and usually takes from several hours to a day. It is recommended to use an SSD hard disk to increase the synchronization speed.

5. Check the node synchronization status

After starting the node, the terminal will continue to output information such as block height. You can also query the synchronization status through the RPC API:

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_syncing","params":[],"id":1}' https://testnet-rpc.juchain.org

6. Open Node RPC Service

Add parameters when starting the node:

./juchain --rpc --rpcaddr 0.0.0.0 --rpcport 8545

• --rpc Enable RPC service

• --rpcaddr Set the listening address

• --rpcport set port

7. Troubleshooting common node issues

• The port is occupied : Please check whether ports 8545, 30303, etc. are occupied by other programs.

• Synchronization stuck : Try restarting the node or checking the network connection.

• Data corruption : Try deleting the data directory and resynchronizing (note the backup key).

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JSON-RPC API calls

1. Supported APIs

JuChain is compatible with Ethereum JSON-RPC API. Common interfaces include eth_blockNumber , eth_getBalance , eth_sendRawTransaction , etc.

2. Call RPC via curl

Query block height:

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}' https://rpc.juchain.org

Check account balance:

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYourAddress","latest"],"id":1}' https://rpc.juchain.org

3. Web3.js/ethers.js connection example

Web3.js：

const Web3 = require('web3');
const web3 = new Web3('https://rpc.juchain.org');
web3.eth.getBlockNumber().then(console.log);

ethers.js：

import { ethers } from "ethers";
const provider = new ethers.providers.JsonRpcProvider("https://rpc.juchain.org");
provider.getBlockNumber().then(console.log);

4. WebSocket support

Mainnet WebSocket address: wss://ws.juchain.org Testnet WebSocket address: ws://testnet-ws.juchain.org

5. Listen to on-chain events

Take ethers.js as an example:

const provider = new ethers.providers.WebSocketProvider("wss://ws.juchain.org");
provider.on("block", (blockNumber) => {
  console.log("New block:", blockNumber);
});

6. Common API call errors and troubleshooting

• Return 403/401 : Please check whether the RPC node is open to the public or whether there are any access restrictions.

• Timeout/No response : Check the network connection or whether the node has completed synchronization.

• Data format error : Please ensure that the request body is in the standard JSON-RPC format.

API Request Limits Update (2025.07.25)

1. Request Rate Limit

Interface Restriction: A rate limit has been applied to the eth_getLogs and eth_getFilterLogs interfaces. Each interface can be called up to 200 times within a 10-second window. Once the threshold is exceeded, further requests will be denied to maintain system stability.

2. Block Range Limit

Interface Restriction: To improve query efficiency and reduce data load, a block range limit has been introduced for the eth_getLogs and eth_getFilterLogs interfaces. Users must ensure the block range specified in the query does not exceed the configured maximum. Queries exceeding the limit will be rejected.

3. Removal of debug_ Methods

Interface Restriction: All methods under the debug_ namespace are no longer supported and have been completely removed. Examples include: debug_traceTransaction, debug_traceBlock, and other debug-related methods.

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JuChain Network Information

• Mainnet RPC: https://rpc.juchain.org

• Mainnet WebSocket: wss://ws.juchain.org

• Mainnet Chain ID: 210000

• Testnet RPC: https://testnet-rpc.juchain.org

• Testnet WebSocket: ws://testnet-ws.juchain.org

• Testnet Chain ID: 202599

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If you need more detailed node building scripts, API examples, or encounter specific errors, please refer to the developer guide or contact the official community support.