/* eslint-disable n8n-nodes-base/node-filename-against-convention */ import type { IDataObject, IDeferredPromise, IExecuteResponsePromiseData, INodeExecutionData, INodeProperties, INodeType, INodeTypeDescription, IRun, ITriggerFunctions, ITriggerResponse, } from 'n8n-workflow'; import { NodeOperationError } from 'n8n-workflow'; import { rabbitDefaultOptions } from './DefaultOptions'; import { MessageTracker, rabbitmqConnectQueue } from './GenericFunctions'; export class RabbitMQTrigger implements INodeType { description: INodeTypeDescription = { displayName: 'RabbitMQ Trigger', name: 'rabbitmqTrigger', // eslint-disable-next-line n8n-nodes-base/node-class-description-icon-not-svg icon: 'file:rabbitmq.png', group: ['trigger'], version: 1, description: 'Listens to RabbitMQ messages', eventTriggerDescription: '', defaults: { name: 'RabbitMQ Trigger', }, triggerPanel: { header: '', executionsHelp: { inactive: "While building your workflow, click the 'listen' button, then trigger a Rabbit MQ event. This will trigger an execution, which will show up in this editor.

Once you're happy with your workflow, activate it. Then every time a change is detected, the workflow will execute. These executions will show up in the executions list, but not in the editor.", active: "While building your workflow, click the 'listen' button, then trigger a Rabbit MQ event. This will trigger an execution, which will show up in this editor.

Your workflow will also execute automatically, since it's activated. Every time a change is detected, this node will trigger an execution. These executions will show up in the executions list, but not in the editor.", }, activationHint: "Once you’ve finished building your workflow, activate it to have it also listen continuously (you just won’t see those executions here).", }, inputs: [], outputs: ['main'], credentials: [ { name: 'rabbitmq', required: true, }, ], properties: [ { displayName: 'Queue / Topic', name: 'queue', type: 'string', default: '', placeholder: 'queue-name', description: 'The name of the queue to read from', }, { displayName: 'Options', name: 'options', type: 'collection', default: {}, placeholder: 'Add Option', options: [ { displayName: 'Content Is Binary', name: 'contentIsBinary', type: 'boolean', default: false, description: 'Whether to save the content as binary', }, { displayName: 'Delete From Queue When', name: 'acknowledge', type: 'options', options: [ { name: 'Execution Finishes', value: 'executionFinishes', description: 'After the workflow execution finished. No matter if the execution was successful or not.', }, { name: 'Execution Finishes Successfully', value: 'executionFinishesSuccessfully', description: 'After the workflow execution finished successfully', }, { name: 'Immediately', value: 'immediately', description: 'As soon as the message got received', }, { name: 'Specified Later in Workflow', value: 'laterMessageNode', description: 'Using a RabbitMQ node to remove the item from the queue', }, ], default: 'immediately', description: 'When to acknowledge the message', }, { displayName: 'JSON Parse Body', name: 'jsonParseBody', type: 'boolean', displayOptions: { hide: { contentIsBinary: [true], }, }, default: false, description: 'Whether to parse the body to an object', }, { displayName: 'Only Content', name: 'onlyContent', type: 'boolean', displayOptions: { hide: { contentIsBinary: [true], }, }, default: false, description: 'Whether to return only the content property', }, { displayName: 'Parallel Message Processing Limit', name: 'parallelMessages', type: 'number', default: -1, displayOptions: { hide: { acknowledge: ['immediately'], }, }, description: 'Max number of executions at a time. Use -1 for no limit.', }, ...rabbitDefaultOptions, ].sort((a, b) => { if ( (a as INodeProperties).displayName.toLowerCase() < (b as INodeProperties).displayName.toLowerCase() ) { return -1; } if ( (a as INodeProperties).displayName.toLowerCase() > (b as INodeProperties).displayName.toLowerCase() ) { return 1; } return 0; }) as INodeProperties[], }, { displayName: "To delete an item from the queue, insert a RabbitMQ node later in the workflow and use the 'Delete from queue' operation", name: 'laterMessageNode', type: 'notice', displayOptions: { show: { '/options.acknowledge': ['laterMessageNode'], }, }, default: '', }, ], }; async trigger(this: ITriggerFunctions): Promise { const queue = this.getNodeParameter('queue') as string; const options = this.getNodeParameter('options', {}) as IDataObject; const channel = await rabbitmqConnectQueue.call(this, queue, options); let parallelMessages = options.parallelMessages !== undefined && options.parallelMessages !== -1 ? parseInt(options.parallelMessages as string, 10) : -1; if (parallelMessages === 0 || parallelMessages < -1) { throw new NodeOperationError( this.getNode(), 'Parallel message processing limit must be greater than zero (or -1 for no limit)', ); } if (this.getMode() === 'manual') { // Do only catch a single message when executing manually, else messages will leak parallelMessages = 1; } let acknowledgeMode = options.acknowledge ? options.acknowledge : 'immediately'; if (parallelMessages !== -1 && acknowledgeMode === 'immediately') { // If parallel message limit is set, then the default mode is "executionFinishes" // unless acknowledgeMode got set specifically. Be aware that the mode "immediately" // can not be supported in this case. acknowledgeMode = 'executionFinishes'; } const messageTracker = new MessageTracker(); let consumerTag: string; let closeGotCalled = false; const startConsumer = async () => { if (parallelMessages !== -1) { await channel.prefetch(parallelMessages); } channel.on('close', () => { if (!closeGotCalled) { this.emitError(new Error('Connection got closed unexpectedly')); } }); const consumerInfo = await channel.consume(queue, async (message) => { if (message !== null) { try { if (acknowledgeMode !== 'immediately') { messageTracker.received(message); } let content: IDataObject | string = message.content.toString(); const item: INodeExecutionData = { json: {}, }; if (options.contentIsBinary === true) { item.binary = { data: await this.helpers.prepareBinaryData(message.content), }; item.json = message as unknown as IDataObject; message.content = undefined as unknown as Buffer; } else { if (options.jsonParseBody === true) { content = JSON.parse(content); } if (options.onlyContent === true) { item.json = content as IDataObject; } else { message.content = content as unknown as Buffer; item.json = message as unknown as IDataObject; } } let responsePromise: IDeferredPromise | undefined = undefined; let responsePromiseHook: IDeferredPromise | undefined = undefined; if (acknowledgeMode !== 'immediately' && acknowledgeMode !== 'laterMessageNode') { responsePromise = await this.helpers.createDeferredPromise(); } else if (acknowledgeMode === 'laterMessageNode') { responsePromiseHook = await this.helpers.createDeferredPromise(); } if (responsePromiseHook) { this.emit([[item]], responsePromiseHook, undefined); } else { this.emit([[item]], undefined, responsePromise); } if (responsePromise && acknowledgeMode !== 'laterMessageNode') { // Acknowledge message after the execution finished await responsePromise.promise().then(async (data: IRun) => { if (data.data.resultData.error) { // The execution did fail if (acknowledgeMode === 'executionFinishesSuccessfully') { channel.nack(message); messageTracker.answered(message); return; } } channel.ack(message); messageTracker.answered(message); }); } else if (responsePromiseHook && acknowledgeMode === 'laterMessageNode') { await responsePromiseHook.promise().then(() => { channel.ack(message); messageTracker.answered(message); }); } else { // Acknowledge message directly channel.ack(message); } } catch (error) { const workflow = this.getWorkflow(); const node = this.getNode(); if (acknowledgeMode !== 'immediately') { messageTracker.answered(message); } this.logger.error( `There was a problem with the RabbitMQ Trigger node "${node.name}" in workflow "${workflow.id}": "${error.message}"`, { node: node.name, workflowId: workflow.id, }, ); } } }); consumerTag = consumerInfo.consumerTag; }; await startConsumer(); // The "closeFunction" function gets called by n8n whenever // the workflow gets deactivated and can so clean up. const closeFunction = async () => { closeGotCalled = true; try { return await messageTracker.closeChannel(channel, consumerTag); } catch (error) { const workflow = this.getWorkflow(); const node = this.getNode(); this.logger.error( `There was a problem closing the RabbitMQ Trigger node connection "${node.name}" in workflow "${workflow.id}": "${error.message}"`, { node: node.name, workflowId: workflow.id, }, ); } }; return { closeFunction, }; } }