@oneflow/loopback-component-primus

loopback-component-primus

Primus adapter for loopback. It allows you to call loopback's remote methods via websocket.

Getting Started

npm install --save @oneflow/loopback-component-primus

Add the loopback-component-primus component to the server/component-config.json:

"@oneflow/loopback-component-primus": {}

A small change is needed in the server/server.js file, replace:

app.start();

with:

app.server = app.start();

Usage

Call remote methods

The primus client library is exposed at the URL http://<LOOPBACK_URL>/primus/primus.js You will need to import it in your html:

<script type="text/javascript" src="http://<LOOPBACK_URL>/primus/primus.js"></script>

Then, in your code:

const primus = new Primus({
	url: 'http://<LOOPBACK_URL>',
});

Now you will be able to call remote methods using primus.send('invoke', {...});

// Call prototype method:

primus.send('invoke', {
		methodString: 'color.prototype.patchAttributes',
		args: {
			id: 1,
			data: { name: 'black' }
		},
	}, function (err, data) {
		if (err) {
			return alert('Error from server: ' + JSON.stringify(err));
		}

		alert('Record updated: ' + JSON.stringify(data));
	});
		
// Call static method:
primus.send('invoke', {
		methodString: 'color.find',
		args: {
			filter: {
				where: {
					name: 'black'
				}
			}
		},
	}, function (err, data) {
		if (err) return alert('Error from server: ' + JSON.stringify(err));
	
		alert('Find results: ' + JSON.stringify(data));
	});

Remote hooks

Operation hooks will not work with the primus adapter (they work only with the REST adapter). We will use the global remote hooks that works seamless with all adapters. The syntax is slighly different:

app.remotes().before('user.*', function (ctx, next) {
	console.log('methodString', ctx.methodString);
	next();
});

app.remotes().before('**', function (ctx, next) {
	console.log('methodString', ctx.methodString);
	next();
});

Spark

You can find the spark property, in the ctx object.