Can you explain what the JRPC protocol means and how it is used in remote method invocation systems?

JRPC (JSON-RPC) is a remote procedure call protocol that uses JSON for message encoding. It allows a client to invoke methods on a remote server, passing parameters and receiving results in JSON format.

Main features of JSON-RPC:

• Uses JSON for serializing requests and responses.
• Supports calling methods with positional or named parameters.
• Allows receiving a result or error in response to a call.
• Can operate over various transport protocols (HTTP, WebSocket, TCP, etc.).

Example of a JSON-RPC request:

{
  "jsonrpc": "2.0",
  "method": "subtract",
  "params": [42, 23],
  "id": 1
}

Server response:

{
  "jsonrpc": "2.0",
  "result": 19,
  "id": 1
}

In QA and automation testing, JSON-RPC is used for interacting with APIs, allowing to invoke server methods and verify the correctness of responses.