feat(Slack Node): Add emoji reaction filter to Slack Trigger

packages/nodes-base/nodes/Slack/SlackTrigger.node.ts

@@ -235,6 +235,20 @@ export class SlackTrigger implements INodeType {
 						description:
 							'A comma-separated string of encoded user IDs. Choose from the list, or specify IDs using an <a href="https://docs.n8n.io/code/expressions/">expression</a>.',
 					},
+					{
+						displayName: 'Emoji Names to Filter',
+						name: 'reactionEmojis',
+						type: 'string',
+						default: '',
+						placeholder: 'thumbsup, eyes, white_check_mark',
+						description:
+							'Comma-separated list of emoji names to allow (without colons). Leave empty to trigger on any reaction.',
+						displayOptions: {
+							show: {
+								'/trigger': ['reaction_added'],
+							},
+						},
+					},
 				],
 			},
 		],
@@ -381,6 +395,20 @@ export class SlackTrigger implements INodeType {
 			}
 		}
 
+		// Filter by reaction emoji for reaction_added events
+		if (eventType === 'reaction_added' && options.reactionEmojis) {
+			const allowedEmojis = (options.reactionEmojis as string)
+				.split(',')
+				.map((e) => e.trim().toLowerCase())
+				.filter(Boolean);
+			if (allowedEmojis.length > 0) {
+				const reaction = ((req.body.event.reaction as string | undefined) ?? '').toLowerCase();
+				if (!allowedEmojis.includes(reaction)) {
+					return {};
+				}
+			}
+		}
+
 		if (options.resolveIds) {
 			if (req.body.event.user) {
 				if (req.body.event.type === 'reaction_added') {

packages/nodes-base/nodes/Slack/test/SlackTrigger.test.ts

@@ -464,6 +464,151 @@ describe('SlackTrigger Node', () => {
 		});
 	});
 
+	describe('webhook method - reaction emoji filter', () => {
+		const reactionRequest = (reaction: string) => ({
+			body: {
+				type: 'event_callback',
+				event: {
+					type: 'reaction_added',
+					user: 'U456',
+					item: { channel: 'C123', ts: '1234567890.123456' },
+					reaction,
+				},
+			},
+		});
+
+		beforeEach(() => {
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					switch (paramName) {
+						case 'trigger':
+							return ['reaction_added'];
+						case 'watchWorkspace':
+							return false;
+						case 'channelId':
+							return 'C123';
+						case 'downloadFiles':
+							return false;
+						case 'options':
+							return {};
+						default:
+							return defaultValue;
+					}
+				},
+			);
+		});
+
+		it('should trigger when no emoji filter is set', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('thumbsup') as any);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result.workflowData).toBeDefined();
+		});
+
+		it('should trigger when reaction matches the filter', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('thumbsup') as any);
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					if (paramName === 'options') return { reactionEmojis: 'thumbsup' };
+					if (paramName === 'trigger') return ['reaction_added'];
+					if (paramName === 'watchWorkspace') return false;
+					if (paramName === 'channelId') return 'C123';
+					return defaultValue;
+				},
+			);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result.workflowData).toBeDefined();
+		});
+
+		it('should not trigger when reaction does not match the filter', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('eyes') as any);
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					if (paramName === 'options') return { reactionEmojis: 'thumbsup' };
+					if (paramName === 'trigger') return ['reaction_added'];
+					if (paramName === 'watchWorkspace') return false;
+					if (paramName === 'channelId') return 'C123';
+					return defaultValue;
+				},
+			);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result).toEqual({});
+		});
+
+		it('should support multiple comma-separated emoji names', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('eyes') as any);
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					if (paramName === 'options') return { reactionEmojis: 'thumbsup, eyes' };
+					if (paramName === 'trigger') return ['reaction_added'];
+					if (paramName === 'watchWorkspace') return false;
+					if (paramName === 'channelId') return 'C123';
+					return defaultValue;
+				},
+			);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result.workflowData).toBeDefined();
+		});
+
+		it('should match emoji names case-insensitively', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('thumbsup') as any);
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					if (paramName === 'options') return { reactionEmojis: 'ThumbsUp' };
+					if (paramName === 'trigger') return ['reaction_added'];
+					if (paramName === 'watchWorkspace') return false;
+					if (paramName === 'channelId') return 'C123';
+					return defaultValue;
+				},
+			);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result.workflowData).toBeDefined();
+		});
+
+		it('should trim whitespace around emoji names', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('thumbsup') as any);
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					if (paramName === 'options') return { reactionEmojis: ' thumbsup , eyes ' };
+					if (paramName === 'trigger') return ['reaction_added'];
+					if (paramName === 'watchWorkspace') return false;
+					if (paramName === 'channelId') return 'C123';
+					return defaultValue;
+				},
+			);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result.workflowData).toBeDefined();
+		});
+
+		it('should not trigger when filter has entries but reaction is an empty string', async () => {
+			mockWebhookFunctions.getRequestObject.mockReturnValue(reactionRequest('') as any);
+			mockWebhookFunctions.getNodeParameter.mockImplementation(
+				(paramName: string, defaultValue?: any) => {
+					if (paramName === 'options') return { reactionEmojis: 'thumbsup' };
+					if (paramName === 'trigger') return ['reaction_added'];
+					if (paramName === 'watchWorkspace') return false;
+					if (paramName === 'channelId') return 'C123';
+					return defaultValue;
+				},
+			);
+
+			const result = await slackTrigger.webhook!.call(mockWebhookFunctions);
+
+			expect(result).toEqual({});
+		});
+	});
+
 	describe('webhook method - other event scenarios', () => {
 		it('should handle team_join event (no channel extraction needed)', async () => {
 			const mockRequest = {