@hapi/nes

nes

nes adds native WebSocket support to hapi-based application servers. Instead of treating the WebSocket connections as a separate platform with its own security and application context, nes builds on top of the existing hapi architecture to provide a flexible and organic extension.

Protocol version: 2.4.x (different from module version)

• API
• Protocol
• Examples
  • Route invocation
  • Subscriptions
  • Broadcast
  • Route authentication
  • Subscription filter
• Browser Client

API

The full client and server API is available in the API documentation.

Protocol

The nes protocol is described in the Protocol documentation.

Examples

Route invocation

Server

const Hapi = require('@hapi/hapi');
const Nes = require('@hapi/nes');

const server = new Hapi.Server();

const start = async () => {

    await server.register(Nes);
    server.route({
        method: 'GET',
        path: '/h',
        config: {
            id: 'hello',
            handler: (request, h) => {

                return 'world!';
            }
        }
    });

    await server.start();
};

start();

Client

const Nes = require('@hapi/nes');

var client = new Nes.Client('ws://localhost');

const start = async () => {

    await client.connect();
    const payload = await client.request('hello');  // Can also request '/h'
    // payload -> 'world!'
};

start();

Subscriptions

Server

const Hapi = require('@hapi/hapi');
const Nes = require('@hapi/nes');

const server = new Hapi.Server();

const start = async () => {

    await server.register(Nes);
    server.subscription('/item/{id}');
    await server.start();
    server.publish('/item/5', { id: 5, status: 'complete' });
    server.publish('/item/6', { id: 6, status: 'initial' });
};

start();

Client

const Nes = require('@hapi/nes');

const client = new Nes.Client('ws://localhost');
const start = async () => {

    await client.connect();
    const handler = (update, flags) => {

        // update -> { id: 5, status: 'complete' }
        // Second publish is not received (doesn't match)
    };

    client.subscribe('/item/5', handler);
};

start();

Broadcast

Server

const Hapi = require('@hapi/hapi');
const Nes = require('@hapi/nes');

const server = new Hapi.Server();

const start = async () => {

    await server.register(Nes);
    await server.start();
    server.broadcast('welcome!');
};

start();

Client

const Nes = require('@hapi/nes');

const client = new Nes.Client('ws://localhost');
const start = async () => {

    await client.connect();
    client.onUpdate = (update) => {

        // update -> 'welcome!'
    };
};

start();

Route authentication

Server

const Hapi = require('@hapi/hapi');
const Basic = require('@hapi/basic');
const Bcrypt = require('bcrypt');
const Nes = require('@hapi/nes');

const server = new Hapi.Server();

const start = async () => {

    await server.register([Basic, Nes]);

    // Set up HTTP Basic authentication

    const users = {
        john: {
            username: 'john',
            password: '$2a$10$iqJSHD.BGr0E2IxQwYgJmeP3NvhPrXAeLSaGCj6IR/XU5QtjVu5Tm',   // 'secret'
            name: 'John Doe',
            id: '2133d32a'
        }
    };

    const validate = async (request, username, password) => {

        const user = users[username];
        if (!user) {
            return { isValid: false };
        }

        const isValid = await Bcrypt.compare(password, user.password);
        const  credentials = { id: user.id, name: user.name };
        return { isValid, credentials };
    };

    server.auth.strategy('simple', 'basic', { validate });

    // Configure route with authentication

    server.route({
        method: 'GET',
        path: '/h',
        config: {
            id: 'hello',
            handler: (request, h) => {

                return `Hello ${request.auth.credentials.name}`;
            }
        }
    });

    await server.start();
};

start();

Client

const Nes = require('@hapi/nes');

const client = new Nes.Client('ws://localhost');
const start = async () => {

    await client.connect({ auth: { headers: { authorization: 'Basic am9objpzZWNyZXQ=' } } });
    const payload = await client.request('hello')  // Can also request '/h'
    // payload -> 'Hello John Doe'
};

start();

Subscription filter

Server

const Hapi = require('@hapi/hapi');
const Basic = require('@hapi/basic');
const Bcrypt = require('bcrypt');
const Nes = require('@hapi/nes');

const server = new Hapi.Server();

const start = async () => {

    await server.register([Basic, Nes]);

    // Set up HTTP Basic authentication

    const users = {
        john: {
            username: 'john',
            password: '$2a$10$iqJSHD.BGr0E2IxQwYgJmeP3NvhPrXAeLSaGCj6IR/XU5QtjVu5Tm',   // 'secret'
            name: 'John Doe',
            id: '2133d32a'
        }
    };

    const validate = async (request, username, password) => {

        const user = users[username];
        if (!user) {
            return { isValid: false };
        }

        const isValid = await Bcrypt.compare(password, user.password);
        const  credentials = { id: user.id, name: user.name };
        return { isValid, credentials };
    };

    server.auth.strategy('simple', 'basic', 'required', { validate });

    // Set up subscription

    server.subscription('/items', {
        filter: (path, message, options) => {

            return (message.updater !== options.credentials.username);
        }
    });

    await server.start();
    server.publish('/items', { id: 5, status: 'complete', updater: 'john' });
    server.publish('/items', { id: 6, status: 'initial', updater: 'steve' });
};

start();

Client

const Nes = require('@hapi/nes');

const client = new Nes.Client('ws://localhost');

// Authenticate as 'john'

const start = async () => {

    await client.connect({ auth: { headers: { authorization: 'Basic am9objpzZWNyZXQ=' } } });
    const handler = (err, update) => {

        // First publish is not received (filtered due to updater key)
        // update -> { id: 6, status: 'initial', updater: 'steve' }
    };

    client.subscribe('/items', handler);
};

start();

Browser Client

When you require('@hapi/nes') it loads the full module and adds a lot of extra code that is not needed for the browser. The browser will only need the nes client. If you are using CommonJS you can load the client with require('@hapi/nes/lib/client').