nodester JSON-RPC

JSON-RPC middleware for nodester.

• Follows JSON-RPC 2.0 Specification

Installation

Install with NPM

npm install -S nodester-json-rpc

Usage

nodester-json-rpc can only be used with a nodester router:

const Router = require('nodester/router');
const rpc = require('nodester-json-rpc/rpc');

const Path = require('path');


// For example: ../src/app/providers/Users.provider.js
const providersPath = Path.join(process.cwd(), 'src', 'app', 'providers');
const router = new Router({ providersPath });

// Define a route.
router.add.route(
  v1('post /rpc/users'),
  rpc({ providedBy: 'Users' })
);

Then make a POST request with a body formatted like this:

{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "blockById",
    "params": {
      "id": 24232
    }
}

Running middlewares before the provider method

Pass a before option to run one or more middlewares before the resolved provider method is called — useful for authentication, authorization or request enrichment:

router.add.route(
  v1('post /rpc/users'),
  rpc({
    before: [ authenticate, authorize ],
    providedBy: 'Users'
  })
);

before accepts an array of middlewares, or a single middleware function. Each one receives (req, res, next) and runs in order, after the request has been validated (so req.rpc — holding id, method and params — is already populated):

function authenticate(req, res, next) {
  // Short-circuit by responding here (the provider method won't run):
  if (!req.headers.authorization) {
    return res.status(401).json({ error: 'Unauthorized' });
  }

  // Or call next() to continue to the next middleware / provider method:
  return next();
}

A middleware may:

• call next() to proceed to the next middleware, or — once the chain is exhausted — to the provider method;
• end the response without calling next() to short-circuit the call, so the provider method is skipped;
• throw, or call next(error), to reject — the error is returned as a JSON-RPC error response.

License

MIT

Copyright

Copyright 2024-present Mark Khramko