Ethereum Cookbook

How to do it...

We will now learn how to use JSON-RPC to interact with Ethereum:

1. Build a basic JSON-RPC body with four parameters. The parameters are version, method, parameters, and ID:

{    "jsonrpc":"2.0",    "method":"", // method identifier    "params":[], // list of parameters    "id":0 // id}

2. Use the net_peerCount method to return the number of peers connected to a node:

curl -X POST     --data '{"jsonrpc":"2.0","method":"net_peerCount","params":[],"id":74}'    http://localhost:8545

3. You will get a response like this for all the requests you make. Some requests will return a hex value instead of a decimal/string. You may have to convert it to the required format manually:

{
  "id":74,
  "jsonrpc": "2.0",
  "result": "0x2" // 2
}

4. Create the same request ...