Closing amqp promise connection after publishing? - node.js

Question

I'm trying to work out how to close my promise based connections after publishing messages.
I've tried to extrapolate away shared code for my sender and my receiver, so I have a connection file like this:
connector.js
const amqp = require('amqplib');
class Connector {
constructor(RabbitMQUrl) {
this.rabbitMQUrl = RabbitMQUrl;
}
connect() {
return amqp.connect(this.rabbitMQUrl)
.then((connection) => {
this.connection = connection;
process.once('SIGINT', () => {
this.connection.close();
});
return this.connection.createChannel();
})
.catch( (err) => {
console.error('Errrored here');
console.error(err);
});
}
}
module.exports = new Connector(
`amqp://${process.env.AMQP_HOST}:5672`
);
Then my publisher/sender looks like this:
publisher.js
const connector = require('./connector');
class Publisher {
constructor(exchange, exchangeType) {
this.exchange = exchange;
this.exchangeType = exchangeType;
this.durabilityOptions = {
durable: true,
autoDelete: false,
};
}
publish(msg) {
connector.connect()
.then( (channel) => {
let ok = channel.assertExchange(
this.exchange,
this.exchangeType,
this.durabilityOptions
);
return ok
.then( () => {
channel.publish(this.exchange, '', Buffer.from(msg));
return channel.close();
})
.catch( (err) => {
console.error(err);
});
});
}
}
module.exports = new Publisher(
process.env.AMQP_EXCHANGE,
process.env.AMQP_TOPIC
);
But as said, I can't quite work out how to close my connection after calling publish().

Answer 1

You could add a close() function to connector:
close() {
if (this.connection) {
console.log('Connector: Closing connection..');
this.connection.close();
}
}
Publisher:
class Publisher {
constructor(exchange, exchangeType) {
this.exchange = exchange;
this.exchangeType = exchangeType;
this.durabilityOptions = {
durable: true,
autoDelete: false,
};
}
connect() {
return connector.connect().then( (channel) => {
console.log('Connecting..');
return channel.assertExchange(
this.exchange,
this.exchangeType,
this.durabilityOptions
).then (() => {
this.channel = channel;
return Promise.resolve();
}).catch( (err) => {
console.error(err);
});;
});
}
disconnect() {
return this.channel.close().then( () => { return connector.close();});
}
publish(msg) {
this.channel.publish(this.exchange, '', Buffer.from(msg));
};
}
Test.js
'use strict'
const connector = require('./connector');
const publisher = require('./publisher');
publisher.connect().then(() => {
publisher.publish('message');
publisher.publish('message2');
publisher.disconnect();
});