n8n/packages/nodes-base/nodes/MQTT/MqttTrigger.node.ts
कारतोफ्फेलस्क्रिप्ट™ 7a4e9ef5fa
refactor: Remove n8n-core dependency in nodes-base (no-changelog) (#5649)
2023-03-09 18:13:15 +01:00

181 lines
4.5 KiB
TypeScript

import type {
ITriggerFunctions,
IDataObject,
INodeType,
INodeTypeDescription,
ITriggerResponse,
} from 'n8n-workflow';
import { NodeOperationError } from 'n8n-workflow';
import mqtt from 'mqtt';
export class MqttTrigger implements INodeType {
description: INodeTypeDescription = {
displayName: 'MQTT Trigger',
name: 'mqttTrigger',
icon: 'file:mqtt.svg',
group: ['trigger'],
version: 1,
description: 'Listens to MQTT events',
defaults: {
name: 'MQTT Trigger',
},
inputs: [],
outputs: ['main'],
credentials: [
{
name: 'mqtt',
required: true,
},
],
properties: [
{
displayName: 'Topics',
name: 'topics',
type: 'string',
default: '',
description:
'Topics to subscribe to, multiple can be defined with comma. Wildcard characters are supported (+ - for single level and # - for multi level). By default all subscription used QoS=0. To set a different QoS, write the QoS desired after the topic preceded by a colom. For Example: topicA:1,topicB:2',
},
{
displayName: 'Options',
name: 'options',
type: 'collection',
placeholder: 'Add Option',
default: {},
options: [
{
displayName: 'JSON Parse Body',
name: 'jsonParseBody',
type: 'boolean',
default: false,
description: 'Whether to try parse the message to an object',
},
{
displayName: 'Only Message',
name: 'onlyMessage',
type: 'boolean',
default: false,
description: 'Whether to return only the message property',
},
],
},
],
};
async trigger(this: ITriggerFunctions): Promise<ITriggerResponse> {
const credentials = await this.getCredentials('mqtt');
const topics = (this.getNodeParameter('topics') as string).split(',');
const topicsQoS: IDataObject = {};
for (const data of topics) {
const [topic, qos] = data.split(':');
topicsQoS[topic] = qos ? { qos: parseInt(qos, 10) } : { qos: 0 };
}
const options = this.getNodeParameter('options') as IDataObject;
if (!topics) {
throw new NodeOperationError(this.getNode(), 'Topics are mandatory!');
}
const protocol = (credentials.protocol as string) || 'mqtt';
const host = credentials.host as string;
const brokerUrl = `${protocol}://${host}`;
const port = (credentials.port as number) || 1883;
const clientId =
(credentials.clientId as string) || `mqttjs_${Math.random().toString(16).substr(2, 8)}`;
const clean = credentials.clean as boolean;
const ssl = credentials.ssl as boolean;
const ca = credentials.ca as string;
const cert = credentials.cert as string;
const key = credentials.key as string;
const rejectUnauthorized = credentials.rejectUnauthorized as boolean;
let client: mqtt.MqttClient;
if (!ssl) {
const clientOptions: mqtt.IClientOptions = {
port,
clean,
clientId,
};
if (credentials.username && credentials.password) {
clientOptions.username = credentials.username as string;
clientOptions.password = credentials.password as string;
}
client = mqtt.connect(brokerUrl, clientOptions);
} else {
const clientOptions: mqtt.IClientOptions = {
port,
clean,
clientId,
ca,
cert,
key,
rejectUnauthorized,
};
if (credentials.username && credentials.password) {
clientOptions.username = credentials.username as string;
clientOptions.password = credentials.password as string;
}
client = mqtt.connect(brokerUrl, clientOptions);
}
const manualTriggerFunction = async () => {
await new Promise((resolve, reject) => {
client.on('connect', () => {
client.subscribe(topicsQoS as mqtt.ISubscriptionMap, (err, _granted) => {
if (err) {
reject(err);
}
client.on('message', (topic: string, message: Buffer | string) => {
let result: IDataObject = {};
message = message.toString();
if (options.jsonParseBody) {
try {
message = JSON.parse(message.toString());
} catch (error) {}
}
result.message = message;
result.topic = topic;
if (options.onlyMessage) {
//@ts-ignore
result = [message as string];
}
this.emit([this.helpers.returnJsonArray(result)]);
resolve(true);
});
});
});
client.on('error', (error) => {
reject(error);
});
});
};
if (this.getMode() === 'trigger') {
await manualTriggerFunction();
}
async function closeFunction() {
client.end();
}
return {
closeFunction,
manualTriggerFunction,
};
}
}