✨ Add Local File Trigger Node (#2375)

* ✨ Add File System Watch Trigger Node

* ⚡ Improvements

packages/nodes-base/nodes/LocalFileTrigger.node.ts

@@ -0,0 +1,219 @@
+import { ITriggerFunctions } from 'n8n-core';
+import {
+	IDataObject,
+	INodeType,
+	INodeTypeDescription,
+	ITriggerResponse,
+} from 'n8n-workflow';
+
+import { watch } from 'chokidar';
+
+
+export class LocalFileTrigger implements INodeType {
+	description: INodeTypeDescription = {
+		displayName: 'Local File Trigger',
+		name: 'localFileTrigger',
+		icon: 'fa:folder-open',
+		group: ['trigger'],
+		version: 1,
+		subtitle: '=Path: {{$parameter["path"]}}',
+		description: 'Triggers a workflow on file system changes',
+		defaults: {
+			name: 'Local File Trigger',
+			color: '#404040',
+		},
+		inputs: [],
+		outputs: ['main'],
+		properties: [
+			{
+				displayName: 'Trigger on',
+				name: 'triggerOn',
+				type: 'options',
+				options: [
+					{
+						name: 'Changes to a Specific File',
+						value: 'file',
+					},
+					{
+						name: 'Changes Involving a Specific Folder',
+						value: 'folder',
+					},
+				],
+				required: true,
+				default: '',
+			},
+			{
+				displayName: 'File to Watch',
+				name: 'path',
+				type: 'string',
+				displayOptions: {
+					show: {
+						triggerOn: [
+							'file',
+						],
+					},
+				},
+				default: '',
+				placeholder: '/data/invoices/1.pdf',
+			},
+			{
+				displayName: 'Folder to Watch',
+				name: 'path',
+				type: 'string',
+				displayOptions: {
+					show: {
+						triggerOn: [
+							'folder',
+						],
+					},
+				},
+				default: '',
+				placeholder: '/data/invoices',
+			},
+			{
+				displayName: 'Watch for',
+				name: 'events',
+				type: 'multiOptions',
+				displayOptions: {
+					show: {
+						triggerOn: [
+							'folder',
+						],
+					},
+				},
+				options: [
+					{
+						name: 'File Added',
+						value: 'add',
+						description: 'Triggers whenever a new file was added',
+					},
+					{
+						name: 'File Changed',
+						value: 'change',
+						description: 'Triggers whenever a file was changed',
+					},
+					{
+						name: 'File Deleted',
+						value: 'unlink',
+						description: 'Triggers whenever a file was deleted',
+					},
+					{
+						name: 'Folder Added',
+						value: 'addDir',
+						description: 'Triggers whenever a new folder was added',
+					},
+					{
+						name: 'Folder Deleted',
+						value: 'unlinkDir',
+						description: 'Triggers whenever a folder was deleted',
+					},
+				],
+				required: true,
+				default: [],
+				description: 'The events to listen to',
+			},
+
+			{
+				displayName: 'Options',
+				name: 'options',
+				type: 'collection',
+				placeholder: 'Add Option',
+				default: {},
+				options: [
+					{
+						displayName: 'Include Linked Files/Folders',
+						name: 'followSymlinks',
+						type: 'boolean',
+						default: true,
+						description: 'When activated, linked files/folders will also be watched (this includes symlinks, aliases on MacOS and shortcuts on Windows). Otherwise only the links themselves will be monitored).',
+					},
+					{
+						displayName: 'Ignore',
+						name: 'ignored',
+						type: 'string',
+						default: '',
+						placeholder: '**/*.txt',
+						description: 'Files or paths to ignore. The whole path is tested, not just the filename. Supports <a href="https://github.com/micromatch/anymatch">Anymatch</a>- syntax.',
+					},
+					{
+						displayName: 'Max Folder Depth',
+						name: 'depth',
+						type: 'options',
+						options: [
+							{
+								name: 'Unlimited',
+								value: -1,
+							},
+							{
+								name: '5 Levels Down',
+								value: 5,
+							},
+							{
+								name: '4 Levels Down',
+								value: 4,
+							},
+							{
+								name: '3 Levels Down',
+								value: 3,
+							},
+							{
+								name: '2 Levels Down',
+								value: 2,
+							},
+							{
+								name: '1 Levels Down',
+								value: 1,
+							},
+							{
+								name: 'Top Folder Only',
+								value: 0,
+							},
+						],
+						default: -1,
+						description: 'How deep into the folder structure to watch for changes',
+					},
+				],
+			},
+
+		],
+	};
+
+
+	async trigger(this: ITriggerFunctions): Promise<ITriggerResponse> {
+		const triggerOn = this.getNodeParameter('triggerOn') as string;
+		const path = this.getNodeParameter('path') as string;
+		const options = this.getNodeParameter('options', {}) as IDataObject;
+
+		let events: string[];
+		if (triggerOn === 'file') {
+			events = [ 'change' ];
+		} else {
+			events = this.getNodeParameter('events', []) as string[];
+		}
+
+		const watcher = watch(path, {
+			ignored: options.ignored,
+			persistent: true,
+			ignoreInitial: true,
+			followSymlinks: options.followSymlinks === undefined ? true : options.followSymlinks as boolean,
+			depth: [-1, undefined].includes(options.depth as number) ? undefined : options.depth as number,
+		});
+
+		const executeTrigger = (event: string, path: string) => {
+			this.emit([this.helpers.returnJsonArray([{ event,path }])]);
+		};
+
+		for (const eventName of events) {
+			watcher.on(eventName, path => executeTrigger(eventName, path));
+		}
+
+		function closeFunction() {
+			return watcher.close();
+		}
+
+		return {
+			closeFunction,
+		};
+
+	}
+}

packages/nodes-base/package.json

@@ -469,6 +469,7 @@
       "dist/nodes/Line/Line.node.js",
       "dist/nodes/LingvaNex/LingvaNex.node.js",
       "dist/nodes/LinkedIn/LinkedIn.node.js",
+      "dist/nodes/LocalFileTrigger.node.js",
       "dist/nodes/Magento/Magento2.node.js",
       "dist/nodes/MailerLite/MailerLite.node.js",
       "dist/nodes/MailerLite/MailerLiteTrigger.node.js",
@@ -665,6 +666,7 @@
     "@types/tmp": "^0.2.0",
     "@types/uuid": "^8.3.0",
     "@types/xml2js": "^0.4.3",
+    "chokidar": "^3.5.2",
     "gulp": "^4.0.0",
     "jest": "^26.4.2",
     "n8n-workflow": "~0.74.0",