Microservice framework based on native Node.js HTTP module and AMQP protocol with express middleware & built-in prometheus. 🔬 🐇
$ npm i micromq$ RABBIT_URL=amqp://localhost node tests/apps/users.js &
$ RABBIT_URL=amqp://localhost node tests/apps/balances.js &
$ RABBIT_URL=amqp://localhost PORT=3000 node tests/apps/gateway.js &
$ PORT=3000 npm testThere are some simple examples.
options<Object>
This method creates gateway.
const Gateway = require('micromq/gateway');
const gateway = new Gateway({
microservices: ['users', 'orders'],
rabbit: {
url: 'amqp://localhost:5672',
},
requests: {
timeout: 5000,
},
});This method creates RPC action.
const Gateway = require('micromq/gateway');
const { Users } = require('./db');
const gateway = new Gateway({ ... });
gateway.action('increase_balance', async (meta, res) => {
if (!meta.amount || Number.isNaN(+meta.amount)) {
res.status(400);
res.json({ error: 'Bad data' });
return;
}
await Users.updateOne({
userId: meta.userId,
}, {
$inc: {
balance: meta.amount,
},
});
res.json({ ok: true });
});
gateway.listen(3000);const MicroMQ = require('micromq');
const app = new MicroMQ({ ... });
app.post('/deposit', (req, res) => {
// send rpc action to the gateway
res.json({
server: {
action: 'increase_balance',
meta: {
userId: 1,
amount: 500,
},
},
});
});
app.start();This method creates application event (read more).
const MicroMQ = require('micromq');
const app = new MicroMQ({ ... });
// register event
app.on('error', (err, req, res) => {
console.error(err); // 'Random error!'
});
app.use(async (req, res, next) => {
try {
await next();
} catch (err) {
res.status(err.status || 500);
res.json({ error: err.message || 'Server error' });
// emit event
app.emit('error', err, req, res);
}
});
app.post('/throw', (req, res) => {
throw 'Random error!';
});
app.start();name<string> Event name...args<...any> - Arguments
This method emits application event.
This method enables prometheus monitoring.
const Gateway = require('micromq/gateway');
const gateway = new Gateway({ ... });
// start prometheus with default /metrics endpoint & without credentials
gateway.enablePrometheus();
// start prometheus with /users/metrics endpoint & without credentials
gateway.enablePrometheus('/users/metrics');
// start prometheus with /users/metrics endpoint & credentials
gateway.enablePrometheus('/users/metrics', {
user: 'admin',
password: 'admin',
});
// start prometheus with default /metrics endpoint & credentials
gateway.enablePrometheus({
user: 'admin',
password: 'admin',
});
gateway.listen(3000);...middlewares<...function> Middlewares
This method adds middlewares.
This method creates endpoint for all HTTP-methods.
This method creates endpoint with needed method.
- returns: <function>
This method returns middleware for express.
const express = require('express');
const bodyParser = require('body-parser');
const Gateway = require('micromq/gateway');
const users = require('./routers/users');
const app = express();
const gateway = new Gateway({ ... });
app.use(bodyParser.json());
// apply middleware
app.use(gateway.middleware());
// monolith router
app.use('/users', users);
// delegate requests to the microservice
app.use('/orders', (req, res) => res.delegate('orders'));port<number> Port for listen.
This method creates HTTP-server and starts listen needed port.
options<Object>
This method creates microservice.
const MicroMQ = require('micromq');
const app = new MicroMQ({
microservice: 'users',
rabbit: {
url: 'amqp://localhost:5672',
},
});This method creates RPC action.
const MicroMQ = require('micromq');
const { Users } = require('./db');
const app = new MicroMQ({ ... });
app.action('new_deposit', async (meta, res) => {
await Users.updateOne({
userId: meta.userId,
}, {
$inc: {
level: 1,
},
});
res.json({ ok: true });
});
app.start();This method enables prometheus monitoring.
const MicroMQ = require('micromq');
const app = new MicroMQ({ ... });
// start prometheus with default /metrics endpoint & without credentials
app.enablePrometheus();
// start prometheus with /users/metrics endpoint & without credentials
app.enablePrometheus('/users/metrics');
// start prometheus with /users/metrics endpoint & credentials
app.enablePrometheus('/users/metrics', {
user: 'admin',
password: 'admin',
});
// start prometheus with default /metrics endpoint & credentials
app.enablePrometheus({
user: 'admin',
password: 'admin',
});
app.start();...middlewares<...function> Middlewares
This method adds middlewares.
This method creates endpoint for all HTTP-methods.
This method creates endpoint with needed method.
name<string> Microservice for askquery<Object>- returns: <Promise<Object>> { status: <number>, response: <any> }
This method asks other microservice.
const MicroMQ = require('micromq');
const app = new MicroMQ({
...,
microservices: ['balances'],
});
app.get('/users/me/info', async (req, res) => {
// ask microservice endpoint
const { response } = await app.ask('balances', {
path: '/balances/me',
method: 'get',
params: {
userId: req.params.id,
},
});
// ask microservice action
const { response } = await app.ask('balances', {
server: {
action: 'new_deposit',
meta: {
amount: 250,
},
},
});
res.json({
id: req.params.id,
name: `${req.session.first_name} ${req.session.last_name}`,
balance: response.amount,
});
});
app.start();port<number> Port for listen.
This method creates HTTP-server and starts listen needed port. The usual use case for this method is run tests.
This method starts microservice.